Rename the fast preview to the shaded preview

Its shader files, the name they are registered under, its members and
the panel text now match what it does: shading only, no geometry.

TEXTURE_DISPLACEMENT.md

@@ -323,10 +323,10 @@ checkbox) that puts triangles where the *displaced surface actually bends*, not
 a linear **ramp** needs no extra vertices (linear interpolation is exact for a ramp); what needs them is
 **curvature** - the *second* derivative, not the gradient. So the extra predicate is a **chord-error**
 test: sample the combined displacement at the triangle's three edge midpoints *and its centroid*
-(sampling the interior is what catches a bump sitting inside a triangle, the blind spot of an edge-only
+(sampling the interior is what catches a hill sitting inside a triangle, the blind spot of an edge-only
 test) and take the largest departure from the flat triangle's barycentric interpolation. Refine while
 that exceeds `chord_tolerance_mm` ("Detail (mm)"). Zero chord error on a ramp ⇒ untouched; high on a
-bump/ridge/noise ⇒ refined until captured. Same conformal machinery, so still crack-free. The
+hill/ridge/noise ⇒ refined until captured. Same conformal machinery, so still crack-free. The
 per-triangle error is cached and recomputed only for the children of a split.
 
 Four knobs bracket it, and all four matter:
@@ -351,9 +351,9 @@ heights are sampled lazily, so a small patch on a huge model never pays for the
 
 ### Fast preview (GPU-only, no CPU meshing)
 
-`resources/shaders/{110,140}/texture_displacement_bump.{vs,fs}`, registered as
+`resources/shaders/{110,140}/texture_displacement_shaded.{vs,fs}`, registered as
-`"texture_displacement_bump"`. Shades the *displaced* surface without moving geometry - active-layer
+`"texture_displacement_shaded"`. Shades the *displaced* surface without moving geometry - active-layer
-only, selected from the View row, and the default when the gizmo opens (`m_use_bump_preview = true`).
+only, selected from the View row, and the default when the gizmo opens (`m_use_shaded_preview = true`).
 Vertex format is `GLModel::Geometry::EVertexLayout::P3N3T2`: `normal.x` carries the per-vertex paint
 weight (0/1), `normal.y` flags the UV island currently being dragged, and `tex_coord` carries a
 precomputed texture UV, so it can use `GLModel` normally instead of a hand-rolled VBO/VAO manager.
@@ -366,7 +366,7 @@ normal from screen-space derivatives of position, not from a per-vertex normal.
 
 **Both preview meshes work in the patch's vertex space, not the mesh's.** Those agree only until a
 *brush* stroke splits a triangle: `get_facets_strict()` then appends the split vertices, so the patch
-array is longer. `rebuild_bump_preview_mesh()` and `rebuild_uvcheck_mesh()` therefore index
+array is longer. `rebuild_shaded_preview_mesh()` and `rebuild_uvcheck_mesh()` therefore index
 `patch.vertices` throughout. The weight buffer is rebuilt at the same cadence as the true-displacement
 preview (stroke-end/slider-release) but from the **live** `TriangleSelector` state, not the flushed model
 facets, so it does not lag by a full model round-trip.
@@ -395,7 +395,7 @@ the bake's.
   captures the true on-screen rate of change however the chart is stretched. This path is also what makes
   the fast preview follow the UV editor: move an island and its uv - hence its shading - moves with it
   (the mesh rebuilds on drag-end, `on_island_edited(finished)` → `rebuild_preview()` →
-  `rebuild_bump_preview_mesh()`). The branch is uniform and the paint weight gates by multiply, so the
+  `rebuild_shaded_preview_mesh()`). The branch is uniform and the paint weight gates by multiply, so the
   texture derivatives stay well defined. A triangle straddling a seam has a discontinuous uv → the
   `det≈0` guard skips it (a localised preview-only artifact, never in the bake).
 
@@ -425,7 +425,7 @@ flow. Two uniforms exist for this: `midlevel` (parallax needs the real height, n
 and `eye_model_pos` (the camera in the volume's local frame).
 
 Parallax cannot change the model's silhouette or cast shadows; the View row's Normal mode is one click
-away for that. The LSCM path stays plain Mikkelsen bump - it has no closed-form uv, so there is no cheap
+away for that. The LSCM path stays plain Mikkelsen normal perturbation - it has no closed-form uv, so there is no cheap
 way to re-project a marched position. One further approximation: the GPU sampler's wrap mode stands in
 for `tile_enabled`/`tile_method`, so with tiling *off* the GPU repeats where the CPU returns 0 outside
 `[0,1)`.
@@ -558,8 +558,8 @@ gizmo via `CommandFn`; view-only ones (Frame, Snap) it handles directly.
 - `src/slic3r/GUI/UVEditorCanvas.hpp/.cpp` - the 2D UV unwrap viewer widget.
 - `src/slic3r/GUI/Plater.hpp/.cpp` - `uv_editor_canvas` member, AUI pane registration,
   `get_uv_editor_canvas()`/`show_uv_editor()`.
-- `src/slic3r/GUI/GLShadersManager.cpp` - registers `"texture_displacement_bump"`.
+- `src/slic3r/GUI/GLShadersManager.cpp` - registers `"texture_displacement_shaded"`.
-- `resources/shaders/{110,140}/texture_displacement_bump.{vs,fs}` - the fast-preview shader.
+- `resources/shaders/{110,140}/texture_displacement_shaded.{vs,fs}` - the fast-preview shader.
 - `src/slic3r/GUI/Gizmos/GLGizmoPainterBase.hpp` - `PainterGizmoType::TEXTURE_DISPLACEMENT`.
 - `src/slic3r/GUI/Gizmos/GLGizmosManager.hpp/.cpp` - `EType::TextureDisplacement` registration.
 
@@ -571,7 +571,7 @@ modes (table-driven), the lowest layer ignoring its blend mode, border displace/
 smoothing and its mask guarantees, and adaptive subdivision: conformality (`every_edge_used_twice` on a
 partially-refined cube - an exact crack detector for a closed mesh), the target edge length actually
 being reached, the triangle budget capping the result without opening a crack, curvature-driven
-refinement (a Gaussian bump refines at its centre, a linear ramp adds nothing), and the max-edge
+refinement (a Gaussian hill refines at its centre, a linear ramp adds nothing), and the max-edge
 baseline.
 
 `BUILD_TESTS` is `OFF` in the checked-in build cache; flip it on to run them:

TEXTURE_DISPLACEMENT_GUIDE.md

@@ -79,7 +79,7 @@ radio group; **Wireframe** is an independent toggle. Hover any icon for its tool
 | View | Meaning |
 |------|---------|
 | **Normal** | The true displaced geometry — exactly what **Bake** produces. Rebuilt in the background. |
-| **Fast** | A GPU bump-shaded approximation of the *active layer only*. No real geometry movement — quick to update, not exact. Best while tuning or dragging islands. |
+| **Fast** | A GPU shaded approximation of the *active layer only*. No real geometry movement — quick to update, not exact. Best while tuning or dragging islands. |
 | **Checker** | A test grid painted over the unwrap so you can see stretching (squares stay square where the map isn't distorted). |
 | **Distortion** | A blue→green→red heatmap of how much each area is compressed or stretched in UV space. Needs the **Unwrap (LSCM)** projection. |
 | **Wireframe** | Overlays the mesh edges (white). Independent of the view above; in **Normal** view it sits on the displaced surface. |
@@ -315,7 +315,7 @@ Baking is the exact same algorithm as the **Normal** preview, so what you see is
 - **Not enough detail?** Subdivide or Remesh before painting fine textures.
 - **Inward cuts** (high Midlevel + big Depth) can self-intersect on thin walls or sharp concave
   corners — keep Depth modest there.
-- **Fast vs Normal:** Fast preview shades a bump and shows only the active layer; use it for quick
+- **Fast vs Normal:** Fast preview only shades the relief and shows only the active layer; use it for quick
   tuning and smooth UV dragging, but trust **Normal**/**Bake** for the exact result.
 - **Topology changes drop unbaked paint.** Subdivide-Apply, Remesh, and Simplify replace the mesh, and
   texture-displacement paint isn't remapped across that change (already-baked relief is unaffected).

resources/shaders/110/texture_displacement_shaded.fs

@@ -1,6 +1,6 @@
 #version 110
 
-// See resources/shaders/140/texture_displacement_bump.fs for full documentation; this is the
+// See resources/shaders/140/texture_displacement_shaded.fs for full documentation; this is the
 // GLSL 1.10 compatibility variant (same logic, older syntax).
 
 #define INTENSITY_CORRECTION 0.6
@@ -309,7 +309,7 @@ void main()
     bool have_uv     = false;
 
     if (use_vertex_uv) {
-        // Mikkelsen surface-gradient bump; see the 140 variant for the full rationale. Scale-exact
+        // Mikkelsen surface-gradient normal perturbation; see the 140 variant for the full rationale. Scale-exact
         // for a conformal LSCM map (no global 1/tiling assumption), and gated by the paint weight
         // via a multiply so the branch stays uniform (use_vertex_uv is a uniform).
         vec2 uv = (island_active > 0.5)

resources/shaders/110/texture_displacement_shaded.vs

@@ -1,6 +1,6 @@
 #version 110
 
-// See resources/shaders/140/texture_displacement_bump.vs for full documentation; this is the
+// See resources/shaders/140/texture_displacement_shaded.vs for full documentation; this is the
 // GLSL 1.10 compatibility variant.
 
 uniform mat4 view_model_matrix;

resources/shaders/110/texture_displacement_uvcheck.fs

@@ -22,7 +22,7 @@ uniform vec2  uv_offset;
 uniform bool  use_vertex_uv;
 // The in-shader projection (0 Triplanar, 1 Cylindrical, 2 Spherical) and the painted patch's frame the
 // wrapping ones wrap around, in the texture frame - the same uniforms, and the same formulas, as
-// texture_displacement_bump.fs, so the checker reports the projection the bake will actually use.
+// texture_displacement_shaded.fs, so the checker reports the projection the bake will actually use.
 uniform int   projection_mode;
 uniform vec3  patch_center;
 uniform vec3  patch_axis;
@@ -91,7 +91,7 @@ void main()
     if (any(lessThan(clipping_planes_dots, ZERO)))
         discard;
 
-    // World space anchored at the volume's origin, like the bake and the bump preview.
+    // World space anchored at the volume's origin, like the bake and the shaded preview.
     vec3 triangle_normal = normalize(cross(dFdx(world_pos.xyz), dFdy(world_pos.xyz)));
     vec3 tex_pos = world_pos.xyz - tex_anchor;
     if (volume_mirrored)

resources/shaders/140/texture_displacement_shaded.fs

@@ -1,7 +1,7 @@
 #version 140
 
 // Fast, geometry-free preview of texture displacement: perturbs the *shading* normal from the
-// height texture's local gradient (a bump map), faded out by the per-vertex paint weight. The
+// height texture's local gradient, faded out by the per-vertex paint weight. The
 // true, exact result is what "Bake" produces via libslic3r/TextureDisplacement.cpp on the CPU.
 //
 // The bake displaces each surface point along its normal by H = +/- depth_mm * (h(uv) - midlevel),
@@ -13,7 +13,7 @@
 // derivatives. Two things have to be right for the preview's apparent depth to match the bake's:
 // the tangent frame the gradient is expressed in, and the uv->mm scale that turns a texel
 // difference into a slope. Getting the scale wrong is a uniform flattening (a raw texel difference
-// is dh over one texel step, not over one mm); getting the frame wrong tilts the bump along the
+// is dh over one texel step, not over one mm); getting the frame wrong tilts the relief along the
 // wrong axes.
 //
 // Two projection paths:
@@ -22,7 +22,7 @@
 //     formed analytically (there is a closed-form uv, so 1 uv unit is exactly tiling_scale mm). This
 //     path also runs a parallax step before shading, see below.
 //
-// Parallax. A pure bump map perturbs shading only, so the pattern is welded to the base surface: it
+// Parallax. Perturbing the normal alone shades only, so the pattern is welded to the base surface: it
 // does not shift as the camera orbits and it does not get any deeper as depth_mm grows, which is
 // exactly when the preview stops reading as real geometry. The triplanar path therefore shades at the
 // point the *displaced* surface would show at this pixel rather than at the pixel's own base position.
@@ -56,7 +56,7 @@
 //     assumption, which matters because an LSCM map is conformal, not isometric: the local mm-per-uv
 //     varies across the chart, so a single global 1/tiling factor (what an earlier version used) got
 //     the apparent depth wrong. This path is also what makes the fast preview follow the UV editor:
-//     move an island and its uv -- hence its bump -- moves with it.
+//     move an island and its uv -- hence its relief -- moves with it.
 
 #define INTENSITY_CORRECTION 0.6
 
@@ -124,7 +124,7 @@ uniform vec3       tex_anchor;    // the volume's origin in world space: the tex
 uniform bool       use_vertex_uv; // true: sample at vertex_uv with a derived tangent frame (LSCM)
 // A 2x3 affine (columns packed as lin = (m00, m01, m10, m11), tr = (m02, m12)) applied to the uv of
 // the island currently being dragged in the UV editor (island_active > 0.5). Identity when nothing is
-// dragged, so this whole path is a no-op then. Lets a UV island drag move the bump on the model with
+// dragged, so this whole path is a no-op then. Lets a UV island drag move the relief on the model with
 // only a uniform update 
 uniform vec4       island_delta_lin;
 uniform vec2       island_delta_tr;
@@ -377,7 +377,7 @@ void main()
     bool have_uv     = false;
 
     if (use_vertex_uv) {
-        // Precomputed-uv (LSCM) path - Mikkelsen's surface-gradient bump ("Bump Mapping
+        // Precomputed-uv (LSCM) path - Mikkelsen's surface-gradient normal mapping ("Bump Mapping
         // Unparametrized Surfaces on the GPU"). The perturbed normal is derived straight from the
         // screen-space derivatives of the *sampled height* and the position, so it is scale-exact
         // with no uv->mm assumption at all - which is the whole point here: an LSCM map is conformal,
@@ -388,7 +388,7 @@ void main()
         // use_vertex_uv is a uniform, so this whole branch is uniform control flow and the texture
         // derivatives are well defined; the paint weight gates the result by a plain multiply (k)
         // rather than a per-fragment branch, keeping it that way.
-        // The dragged island's uv rides a uniform affine so its bump moves without a rebuild; every
+        // The dragged island's uv rides a uniform affine so its relief moves without a rebuild; every
         // other vertex (island_active == 0) samples its baked uv unchanged.
         vec2 uv = (island_active > 0.5)
                     ? vec2(dot(island_delta_lin.xy, vertex_uv), dot(island_delta_lin.zw, vertex_uv)) + island_delta_tr

resources/shaders/140/texture_displacement_shaded.vs

@@ -12,7 +12,7 @@ uniform vec4 clipping_plane;
 in vec3 v_position;
 // GLModel's P3N3T2 layout (position + normal + texcoord), reused so this mesh builds and renders
 // like any other GLModel rather than needing a bespoke vertex buffer. The two spare channels carry
-// what the bump preview actually needs per vertex:
+// what the shaded preview actually needs per vertex:
 //   v_normal.x   -- the active layer's paint weight, 0 (untouched) or 1 (painted).
 //   v_normal.y   -- 1 for a vertex of the island currently being dragged in the UV editor, else 0.
 //                   The fragment shader applies island_delta to those vertices' uv, so a UV drag is a

resources/shaders/140/texture_displacement_uvcheck.fs

@@ -8,7 +8,7 @@
 //             where the texture actually lands.
 //   mode 1 - Distortion heatmap: the per-vertex area-distortion carried in `distortion`, blue
 //             (compressed) -> green (ideal) -> red (stretched).
-// Both are lit with the same cheap two-light diffuse the bump preview uses, so the surface still
+// Both are lit with the same cheap two-light diffuse the shaded preview uses, so the surface still
 // reads as 3D.
 
 #define INTENSITY_CORRECTION 0.6
@@ -31,7 +31,7 @@ uniform vec2  uv_offset;
 uniform bool  use_vertex_uv;
 // The in-shader projection (0 Triplanar, 1 Cylindrical, 2 Spherical) and the painted patch's frame the
 // wrapping ones wrap around, in the texture frame - the same uniforms, and the same formulas, as
-// texture_displacement_bump.fs, so the checker reports the projection the bake will actually use.
+// texture_displacement_shaded.fs, so the checker reports the projection the bake will actually use.
 uniform int   projection_mode;
 uniform vec3  patch_center;
 uniform vec3  patch_axis;
@@ -103,7 +103,7 @@ void main()
     if (any(lessThan(clipping_planes_dots, ZERO)))
         discard;
 
-    // World space anchored at the volume's origin, like the bake and the bump preview.
+    // World space anchored at the volume's origin, like the bake and the shaded preview.
     vec3 triangle_normal = normalize(cross(dFdx(world_pos.xyz), dFdy(world_pos.xyz)));
     vec3 tex_pos = world_pos.xyz - tex_anchor;
     if (volume_mirrored)

src/libslic3r/TextureDisplacement.cpp

@@ -134,7 +134,7 @@ struct DecodedTextureCache
 };
 DecodedTextureCache g_decoded_texture_cache;
 
-// The smoothed copy is cached too, one per image: the thumbnail, the bump-preview height texture, the
+// The smoothed copy is cached too, one per image: the thumbnail, the shaded-preview height texture, the
 // colour texture, the projector texture, the UV editor's background and the preview job all ask for
 // the same (image, smoothing) pair in the same frame while the Smoothing slider moves, and each of them
 // blurring its own copy is what froze the UI. Keyed like the raw cache; a different smoothing value
@@ -428,10 +428,10 @@ V2Resolution recommend_v2_resolution(const indexed_triangle_set
                                      const std::vector<TextureDisplacementLayer> &layers,
                                      const Transform3d                           &volume_to_world)
 {
-    // bumpmesh.com's defaults on model load: edge = diagonal / 250 in [0.05, 5] mm, budget 750 k. A
+    // The defaults on model load: edge = diagonal / 250 in [0.05, 5] mm, budget 750 k. A texture-driven
-    // texture-driven variant (BumpMesh's smart resolution) was measured to give better walls on step
+    // variant (resolution from the texture's own detail) was measured to give better walls on step
-    // textures at 2-10x the bake time and up to 2 M output triangles; the user preferred the site's
+    // textures at 2-10x the bake time and up to 2 M output triangles, and was not worth that; these
-    // defaults. The texel size and sharpness are still reported for the panel.
+    // defaults stayed. The texel size and sharpness are still reported for the panel.
     constexpr double EDGE_MIN = 0.05, EDGE_MAX = 5.0, DIAG_DIVISOR = 250.0;
     constexpr int    BUDGET_K = 750;
 
@@ -3480,7 +3480,7 @@ indexed_triangle_set subdivide_mesh_adaptive(const indexed_triangle_set &mesh,
 
     // How far the *displaced* surface departs from the flat triangle, sampled across the WHOLE
     // triangle - the three edge midpoints and the centroid - not just one edge midpoint. Sampling the
-    // interior is what catches a bump that sits inside a triangle (the blind spot of an edge-only
+    // interior is what catches a hill that sits inside a triangle (the blind spot of an edge-only
     // test). Cached per triangle: it can only change when the triangle is split, and then both
     // children are fresh entries.
     std::vector<float> tri_err;

src/libslic3r/TextureDisplacement.hpp

@@ -420,10 +420,9 @@ struct TextureDisplacementOptions
     }
 };
 
-// How much detail a height texture carries, as BumpMesh's smart resolution measures it: central
+// How much detail a height texture carries: central differences of the grey image, the mean gradient
-// differences of the grey image, the mean gradient and the share of texels steeper than 30 grey
+// and the share of texels steeper than 30 grey levels, mapped to how many texels one mesh edge may
-// levels, mapped to how many texels one mesh edge may span (1 for a hard-edged image, 4 for a smooth
+// span (1 for a hard-edged image, 4 for a smooth one). Cached per image, like the decode.
-// one). Cached per image, like the decode.
 struct TextureDetail
 {
     float mean_gradient   = 0.f;
@@ -438,8 +437,8 @@ struct TextureDetail
 TextureDetail analyze_texture_detail(const TextureDisplacementLayer &layer);
 
 // The default pipeline's automatic resolution and budget, when the options leave them at "auto":
-// bumpmesh.com's defaults - edge = the model's world-space diagonal / 250, clamped to [0.05, 5] mm and
+// edge = the model's world-space diagonal / 250, clamped to [0.05, 5] mm and rounded up to 0.01;
-// rounded up to 0.01; budget 750 k. The texel size of the finest layer and its sharpness class are
+// budget 750 k. The texel size of the finest layer and its sharpness class are
 // reported alongside for the panel. `edge_mm` is 0 for an empty mesh.
 struct V2Resolution
 {
@@ -946,10 +945,10 @@ indexed_triangle_set subdivide_mesh_uniform(const indexed_triangle_set &mesh, fl
 //              departs from the flat triangle by more than `chord_tolerance_mm`, measured as the max
 //              over the three edge midpoints AND the centroid of |sampled displacement - the flat
 //              triangle's barycentric interpolation|. Sampling the interior, not just edge midpoints,
-//              is what catches a bump that sits inside a triangle. This is a *curvature* test: it is
+//              is what catches a hill that sits inside a triangle. This is a *curvature* test: it is
 //              exactly zero on a plane or a linear ramp (barycentric interpolation is exact there, so
 //              those stay coarse - the case a gradient criterion would over-refine) and large on a
-//              bump/ridge/noise.
+//              hill/ridge/noise.
 // `min_edge_length_mm` is a hard floor under both: no triangle whose longest edge is already at or
 // below it is ever refined, which is also what guarantees termination across a sharp texture step
 // (where the chord error never falls below the tolerance no matter how fine the mesh gets).

src/slic3r/GUI/GLShadersManager.cpp

@@ -104,8 +104,8 @@ std::pair<bool, std::string> GLShadersManager::init()
         valid &= append_shader("mm_gouraud", { prefix + "mm_gouraud.vs", prefix + "mm_gouraud.fs" }, { "FLIP_TRIANGLE_NORMALS"sv });
     else
         valid &= append_shader("mm_gouraud", { prefix + "mm_gouraud.vs", prefix + "mm_gouraud.fs" });
-    // Fast bump-map preview for the texture displacement gizmo (see libslic3r/TextureDisplacement.hpp).
+    // Fast shaded preview for the texture displacement gizmo (see libslic3r/TextureDisplacement.hpp).
-    valid &= append_shader("texture_displacement_bump", { prefix + "texture_displacement_bump.vs", prefix + "texture_displacement_bump.fs" });
+    valid &= append_shader("texture_displacement_shaded", { prefix + "texture_displacement_shaded.vs", prefix + "texture_displacement_shaded.fs" });
     // UV-check overlay for the same gizmo: a procedural checker or a distortion heatmap over the
     // painted patch, to sanity-check the unwrap.
     valid &= append_shader("texture_displacement_uvcheck", { prefix + "texture_displacement_uvcheck.vs", prefix + "texture_displacement_uvcheck.fs" });

src/slic3r/GUI/Gizmos/GLGizmoTextureDisplacement.cpp

@@ -79,7 +79,7 @@ constexpr int THUMBNAIL_MAX_PX = 128;
 // Everything above is about drawing a ~48 px panel row, and none of it applies to the height texture
 // the fast-preview *shader* samples: that one is magnified across the model, not minified into a
 // row, and every texel it loses is relief the preview cannot show. It gets its own upload at (up to)
-// this size, so the bump preview reads the same height field the bake does instead of a 128 px box
+// this size, so the shaded preview reads the same height field the bake does instead of a 128 px box
 // blur of it - which is what made Fast look flatter and softer than the result it was previewing.
 constexpr int HEIGHT_TEX_MAX_PX = 2048;
 
@@ -224,11 +224,11 @@ constexpr int PALETTE_LUT_EDGE = 24;
 
 // Ceiling on the printable palette, which bounds that fill cost (and the shader's uniform array).
 constexpr int PALETTE_MAX_ENTRIES = 64;
-// Ceiling on the filaments the palette's entries can refer to (the bump shader's filament_rgb[]);
+// Ceiling on the filaments the palette's entries can refer to (the shaded preview shader's filament_rgb[]);
 // mmu segmentation stops at Extruder16 anyway.
 constexpr int PALETTE_MAX_FILAMENTS = 16;
 
-// sRGB (0..1) <-> CIELAB, D65. Exactly what the bump shader's srgb_to_lab() computes, so the CPU
+// sRGB (0..1) <-> CIELAB, D65. Exactly what the preview shader's srgb_to_lab() computes, so the CPU
 // quantizer, the mixed-palette entries and the per-fragment preview all match in the same space.
 // Not slic3r/Utils/ColorSpaceConvert: its RGB2Lab wants 0..1 but its Lab2RGB hands back linear
 // values on a 0..100 scale, and the earlier code fed the former 0..255 and divided the latter by 255 -
@@ -390,10 +390,10 @@ void GLGizmoTextureDisplacement::on_shutdown()
 {
     m_parent.toggle_model_objects_visibility(true);
     m_preview_glmodel.reset();
-    m_bump_preview_glmodel.reset();
+    m_shaded_preview_glmodel.reset();
     m_paint_overlay_glmodel.reset();
     m_paint_overlay_dirty = false;
-    // Any preview still in flight is superseded: bumping the shared counter makes it abort at its next
+    // Any preview still in flight is superseded: raising the shared counter makes it abort at its next
     // progress poll, and its completion handler then finds nothing to do.
     m_preview_generation->fetch_add(1);
     m_preview_job_pending = false;
@@ -410,9 +410,9 @@ void GLGizmoTextureDisplacement::on_shutdown()
     m_subdivide_editing       = false;
     m_subdivide_preview_tris = -1;
     m_subdivide_preview_glmodel.reset();
-    m_bump_active_chart  = -1;
+    m_shaded_active_chart  = -1;
-    m_bump_active_face.clear();
+    m_shaded_active_face.clear();
-    m_bump_island_delta  = Eigen::Matrix<float, 2, 3>::Identity();
+    m_shaded_island_delta  = Eigen::Matrix<float, 2, 3>::Identity();
     m_island_drag_active = false;
     m_island_move_set.clear();
     m_adjust_texture_mode = false;
@@ -461,39 +461,38 @@ void GLGizmoTextureDisplacement::render_painter_gizmo()
     // so it wins the depth test on the coincident (unpainted) surface - keeping the familiar
     // enforcer/blocker highlight for precise brush editing there. Where the surface has actually
     // been displaced, the raised preview geometry legitimately occludes the flat overlay - that
-    // visible bump is itself the "this is painted" indicator in that area.
+    // visible relief is itself the "this is painted" indicator in that area.
     //
-    // The bump preview is different: it never actually moves geometry (it's a shading trick), so
+    // The shaded preview is different: it never actually moves geometry (it only shades), so
     // its depth is identical to the overlay's *everywhere*, not just in the unpainted area - the
-    // depth-biased opaque overlay would win the depth test across the whole surface and hide the bump
+    // depth-biased opaque overlay would win the depth test across the whole surface and hide the relief
     // shading entirely. So render_triangles() is skipped for it. What is *not* skipped is
-    // render_paint_overlay(): leaving the bump shading as the only paint feedback meant a stroke that
+    // render_paint_overlay(): leaving the shading as the only paint feedback meant a stroke that
     // erased paint, or added it with no texture picked, changed nothing on screen until the whole
     // preview rebuilt at stroke end - and in the true-displacement view the opaque overlay is hidden
     // by the raised surface for the same reason. The translucent tint covers both cases.
-    // Coalesced bump rebuild from an in-progress UV island drag (see on_island_edited): done here, at
+    // Coalesced shaded-preview rebuild from an in-progress UV island drag (see on_island_edited): done here, at
     // most once per drawn frame, rather than synchronously in the UV canvas's mouse-move handler.
-    if (m_use_bump_preview && m_bump_preview_dirty) {
+    if (m_use_shaded_preview && m_shaded_preview_dirty) {
-        rebuild_bump_preview_mesh();
+        rebuild_shaded_preview_mesh();
-        m_bump_preview_dirty = false;
+        m_shaded_preview_dirty = false;
     }
     // Same coalescing for the paint tint, but on its own flag: a stroke marks this every mouse move
-    // (see on_mouse()) and it only costs the painted patch, whereas the bump mesh also carries every
+    // (see on_mouse()) and it only costs the painted patch
-    // unpainted triangle of the volume and stays on the stroke-end cadence.
     if (m_paint_overlay_dirty) {
         rebuild_paint_overlay();
         m_paint_overlay_dirty = false;
     }
     rebuild_other_paint_overlay(); // a no-op unless another layer's paint, the active layer or the preview changed
-    // is_initialized() alone is not enough: render_bump_preview_mesh() also needs an active layer
+    // is_initialized() alone is not enough: render_shaded_preview_mesh() also needs an active layer
     // with a decoded texture and a compiled shader, and bails silently without them. Hiding the real
-    // volume for a bump pass that then draws nothing is what made the model vanish - most obviously
+    // volume for a shaded pass that then draws nothing is what made the model vanish - most obviously
     // with zero layers, but equally with a layer that has no texture picked yet.
-    const bool use_bump = m_use_bump_preview && m_bump_preview_glmodel.is_initialized() && bump_preview_ready();
+    const bool use_shaded = m_use_shaded_preview && m_shaded_preview_glmodel.is_initialized() && shaded_preview_ready();
-    const bool use_true_preview = !use_bump && m_preview_glmodel.is_initialized();
+    const bool use_true_preview = !use_shaded && m_preview_glmodel.is_initialized();
     // In Checker/Distortion mode the UV-check overlay *is* the surface visualization the user is
     // looking at, so the opaque paint-selection highlight must not be drawn on top of it - same
-    // reasoning as skipping it for the bump preview (see bug #12). Without this the painted area
+    // reasoning as skipping it for the shaded preview (see bug #12). Without this the painted area
     // covers the checker/heatmap and it can't be seen.
     const bool show_paint_overlay = m_uv_check_mode == UVCheckMode::None;
 
@@ -501,14 +500,14 @@ void GLGizmoTextureDisplacement::render_painter_gizmo()
     // put it back. Getting this wrong leaves an invisible model, so it is decided once, here, rather
     // than per branch below.
     m_parent.toggle_model_objects_visibility(true);
-    if (use_bump || use_true_preview) {
+    if (use_shaded || use_true_preview) {
         if (ModelVolume *mv = texture_volume())
             m_parent.toggle_model_objects_visibility(false, m_c->selection_info()->model_object(),
                                                       m_c->selection_info()->get_active_instance(), mv);
     }
 
-    if (use_bump) {
+    if (use_shaded) {
-        render_bump_preview_mesh();
+        render_shaded_preview_mesh();
     } else if (use_true_preview) {
         render_preview_mesh();
 
@@ -527,11 +526,11 @@ void GLGizmoTextureDisplacement::render_painter_gizmo()
     if (show_paint_overlay)
         render_paint_overlay(m_other_paint_glmodel);
 
-    // The translucent paint tint. Needed in the bump view because the opaque highlight above is
+    // The translucent paint tint. Needed in the shaded view because the opaque highlight above is
     // skipped there, and in the true-displacement view because the displaced surface rises *above*
     // the undisplaced overlay geometry and hides it exactly where the relief is strongest - in both
     // cases leaving an erase stroke with no visible effect until the next full preview rebuild.
-    if (show_paint_overlay && (use_bump || use_true_preview))
+    if (show_paint_overlay && (use_shaded || use_true_preview))
         render_paint_overlay(m_paint_overlay_glmodel);
 
     // The UV editor's island selection, shown on the model. Polled here rather than pushed: the pane
@@ -1123,9 +1122,9 @@ std::vector<Vec2f> GLGizmoTextureDisplacement::compute_layer_corner_uvs(const in
     return corner;
 }
 
-void GLGizmoTextureDisplacement::rebuild_bump_preview_mesh()
+void GLGizmoTextureDisplacement::rebuild_shaded_preview_mesh()
 {
-    m_bump_preview_glmodel.reset();
+    m_shaded_preview_glmodel.reset();
 
     const ModelVolume *mv = texture_volume();
     if (mv == nullptr || m_triangle_selectors.empty())
@@ -1141,13 +1140,13 @@ void GLGizmoTextureDisplacement::rebuild_bump_preview_mesh()
     // No "patch.vertices.size() == mesh vertex count" check here, and that is the point: a *brush*
     // stroke splits triangles, so the selector appends split vertices and the patch array is longer
     // than the mesh's. An earlier version bailed out on that as "shouldn't happen", which meant the
-    // bump model was never built while brushing and render_painter_gizmo() silently fell back to the
+    // shaded model was never built while brushing and render_painter_gizmo() silently fell back to the
     // Normal (true-displacement) preview - Fast looked broken for brush and fine for Face/Connected
     // area, because only the brush splits. Everything below indexes the patch's own vertex array, so
     // the extra vertices are simply carried through.
 
     // Unpainted triangles, so the surrounding surface still renders (the render path hides the real
-    // model in bump mode). get_facets_strict() returns the same vertex array whatever state is asked.
+    // model in shaded mode). get_facets_strict() returns the same vertex array whatever state is asked.
     const indexed_triangle_set rest = m_triangle_selectors[0]->get_facets_strict(EnforcerBlockerType::NONE);
 
     // For LSCM we hand the shader the finished per-vertex texture uv (island placement + tiling/
@@ -1159,22 +1158,22 @@ void GLGizmoTextureDisplacement::rebuild_bump_preview_mesh()
     // carry its own chart's UVs - see compute_layer_corner_uvs().
     const TextureDisplacementLayer *active = active_layer();
     std::vector<Vec2f> corner_uv = active != nullptr ? compute_layer_corner_uvs(patch, *active) : std::vector<Vec2f>{};
-    m_bump_preview_uses_vertex_uv = corner_uv.size() == patch.indices.size() * 3;
+    m_shaded_preview_uses_vertex_uv = corner_uv.size() == patch.indices.size() * 3;
-    if (!m_bump_preview_uses_vertex_uv)
+    if (!m_shaded_preview_uses_vertex_uv)
         corner_uv.clear();
-    m_bump_projection_mode = (active != nullptr && !m_bump_preview_uses_vertex_uv) ?
+    m_shaded_projection_mode = (active != nullptr && !m_shaded_preview_uses_vertex_uv) ?
-                                 layer_projection_frame(patch, *active, m_bump_patch_center, m_bump_patch_axis) : 0;
+                                 layer_projection_frame(patch, *active, m_shaded_patch_center, m_shaded_patch_axis) : 0;
 
     // Which triangles the in-flight UV drag moves. Computed here, against the very patch this mesh is
     // built from, so the flags can never be indexed by a different triangle count than they were sized
     // for (the drag starts from the flushed facet data, a brush stroke changes the live selector).
-    compute_bump_active_faces(m_bump_active_chart >= 0 ? m_island_move_set : std::vector<int>{}, patch.indices.size());
+    compute_shaded_active_faces(m_shaded_active_chart >= 0 ? m_island_move_set : std::vector<int>{}, patch.indices.size());
 
     // Colour is quantized per *fragment* in the shader now (see the .fs), so this mesh carries no
     // colour of its own - the palette and the colour texture are uniforms, and every pixel matches the
     // image rather than the facet it landed on. What the *bake* will produce, at facet resolution, is
     // what the Normal view shows.
-    m_bump_preview_palette = (active != nullptr && active->color_enabled) ? cached_palette()
+    m_shaded_preview_palette = (active != nullptr && active->color_enabled) ? cached_palette()
                                                                          : std::vector<PaletteEntry>{};
 
     GLModel::Geometry init_data;
@@ -1186,7 +1185,7 @@ void GLGizmoTextureDisplacement::rebuild_bump_preview_mesh()
     // painted face of a raw cube has no strictly-interior vertex (all 8 are shared), so per-vertex
     // weighting would either bleed onto the neighbours (boundary weight 1) or vanish outright (boundary
     // weight 0, which is what made a single face show nothing). Duplicating vertices costs no shading
-    // quality here because the bump shader takes its surface normal from screen-space derivatives of
+    // quality here because the preview shader takes its surface normal from screen-space derivatives of
     // position (dFdx/dFdy), not from a per-vertex normal. normal.y flags the UV-editor island being
     // dragged so the shader can move just that island via the island_delta uniform.
     const size_t   tri_total = patch.indices.size() + rest.indices.size();
@@ -1198,10 +1197,10 @@ void GLGizmoTextureDisplacement::rebuild_bump_preview_mesh()
             const stl_triangle_vertex_indices &tri = its.indices[f];
             // One value for the whole triangle: island_active is an interpolated varying, so the three
             // corners have to agree or the shader moves part of a triangle and not the rest.
-            const float act = (painted && f < m_bump_active_face.size() && m_bump_active_face[f]) ? 1.f : 0.f;
+            const float act = (painted && f < m_shaded_active_face.size() && m_shaded_active_face[f]) ? 1.f : 0.f;
             for (int i = 0; i < 3; ++i) {
                 const int   idx = tri[i];
-                const Vec2f uv  = (painted && m_bump_preview_uses_vertex_uv) ? corner_uv[f * 3 + size_t(i)]
+                const Vec2f uv  = (painted && m_shaded_preview_uses_vertex_uv) ? corner_uv[f * 3 + size_t(i)]
                                                                              : Vec2f::Zero();
                 init_data.add_vertex(its.vertices[size_t(idx)], Vec3f(weight, act, 0.f), uv);
             }
@@ -1209,50 +1208,50 @@ void GLGizmoTextureDisplacement::rebuild_bump_preview_mesh()
             vcount += 3;
         }
     };
-    emit_triangles(patch, 1.f, true); // painted -> bumped, and coloured by the shader
+    emit_triangles(patch, 1.f, true); // painted -> shaded as relief, and coloured by the shader
-    // Untouched surface: flat, so it still shows but isn't bumped - and uncoloured, which is what the
+    // Untouched surface: flat, so it still shows but carries no relief - and uncoloured, which is what the
     // bake leaves it as (EnforcerBlockerType::NONE, i.e. the volume's own filament).
     emit_triangles(rest, 0.f, false);
 
-    m_bump_preview_glmodel.init_from(std::move(init_data));
+    m_shaded_preview_glmodel.init_from(std::move(init_data));
     // GLModel::render() unconditionally re-sets the shader's "uniform_color" from this internal
     // color field right before drawing (see GLModel.cpp) - setting the uniform manually in
-    // render_bump_preview_mesh() would just get overwritten by it, so it must be set here instead.
+    // render_shaded_preview_mesh() would just get overwritten by it, so it must be set here instead.
     // GLModel::Geometry defaults to BLACK, which is exactly what showed up before this was added.
-    m_bump_preview_glmodel.set_color(GLVolume::NEUTRAL_COLOR);
+    m_shaded_preview_glmodel.set_color(GLVolume::NEUTRAL_COLOR);
 
     // The mesh now reflects the islands' current placement, so any live drag delta is measured from
     // here: reset it to identity and record the dragged island's baked transform.
-    m_bump_island_delta = Eigen::Matrix<float, 2, 3>::Identity();
+    m_shaded_island_delta = Eigen::Matrix<float, 2, 3>::Identity();
     const TextureDisplacementLayer *al = active_layer();
-    if (m_bump_active_chart >= 0 && al != nullptr) {
+    if (m_shaded_active_chart >= 0 && al != nullptr) {
         const std::vector<Eigen::Matrix<float, 2, 3>> xf = uv_editor_island_transforms(*al);
-        m_bump_baked_active_xf = (size_t(m_bump_active_chart) < xf.size()) ? xf[size_t(m_bump_active_chart)]
+        m_shaded_baked_active_xf = (size_t(m_shaded_active_chart) < xf.size()) ? xf[size_t(m_shaded_active_chart)]
                                                                            : Eigen::Matrix<float, 2, 3>::Identity();
     } else {
-        m_bump_baked_active_xf = Eigen::Matrix<float, 2, 3>::Identity();
+        m_shaded_baked_active_xf = Eigen::Matrix<float, 2, 3>::Identity();
     }
 }
 
-void GLGizmoTextureDisplacement::compute_bump_active_faces(const std::vector<int> &charts, size_t patch_face_count)
+void GLGizmoTextureDisplacement::compute_shaded_active_faces(const std::vector<int> &charts, size_t patch_face_count)
 {
-    m_bump_active_face.clear();
+    m_shaded_active_face.clear();
     if (charts.empty() || patch_face_count == 0)
         return;
     const PatchUnwrap &u = m_uv_editor_unwrap;
     if (u.source_face.size() != u.indices.size())
         return;
-    m_bump_active_face.assign(patch_face_count, 0);
+    m_shaded_active_face.assign(patch_face_count, 0);
     // Flag every triangle of every chart being moved. For a group/multi move that is more than one
     // chart, but since such a move is a pure translation the shader applies the same delta to them all
     // (see on_island_edited) - exactly the "joined islands move together" behaviour.
     for (size_t t = 0; t < u.indices.size(); ++t) {
         const int f  = u.source_face[t];
         const int v0 = u.indices[t][0]; // a triangle lies in one chart, so any corner names it
-        if (f < 0 || size_t(f) >= m_bump_active_face.size() || v0 < 0 || size_t(v0) >= u.vertex_chart.size())
+        if (f < 0 || size_t(f) >= m_shaded_active_face.size() || v0 < 0 || size_t(v0) >= u.vertex_chart.size())
             continue;
         if (std::find(charts.begin(), charts.end(), u.vertex_chart[size_t(v0)]) != charts.end())
-            m_bump_active_face[size_t(f)] = 1;
+            m_shaded_active_face[size_t(f)] = 1;
     }
 }
 
@@ -1313,11 +1312,11 @@ std::vector<int> GLGizmoTextureDisplacement::build_island_move_set(const Texture
     return set;
 }
 
-void GLGizmoTextureDisplacement::render_bump_preview_mesh()
+void GLGizmoTextureDisplacement::render_shaded_preview_mesh()
 {
     const ModelObject *mo = m_c->selection_info()->model_object();
     const ModelVolume  *mv = texture_volume();
-    if (mo == nullptr || mv == nullptr || !m_bump_preview_glmodel.is_initialized())
+    if (mo == nullptr || mv == nullptr || !m_shaded_preview_glmodel.is_initialized())
         return;
 
     const TextureDisplacementLayer *layer = active_layer();
@@ -1334,7 +1333,7 @@ void GLGizmoTextureDisplacement::render_bump_preview_mesh()
     if (tex == nullptr || tex->get_width() <= 0 || tex->get_height() <= 0)
         return;
 
-    GLShaderProgram *shader = wxGetApp().get_shader("texture_displacement_bump");
+    GLShaderProgram *shader = wxGetApp().get_shader("texture_displacement_shaded");
     if (shader == nullptr)
         return;
 
@@ -1401,14 +1400,14 @@ void GLGizmoTextureDisplacement::render_bump_preview_mesh()
     shader->set_uniform("tex_anchor", Vec3f(tex_anchor.cast<float>()));
     shader->set_uniform("eye_model_pos", Vec3f((camera.get_position() - tex_anchor).cast<float>()));
     // When set, the shader samples at the per-vertex uv baked into the mesh (LSCM) rather than
-    // projecting; see rebuild_bump_preview_mesh().
+    // projecting; see rebuild_shaded_preview_mesh().
-    shader->set_uniform("use_vertex_uv", m_bump_preview_uses_vertex_uv);
+    shader->set_uniform("use_vertex_uv", m_shaded_preview_uses_vertex_uv);
     // Cylindrical/Spherical wrap around the painted patch's own centre, which no fragment can derive:
-    // captured with the mesh (see rebuild_bump_preview_mesh()) and handed over here. 0 is the planar
+    // captured with the mesh (see rebuild_shaded_preview_mesh()) and handed over here. 0 is the planar
     // projection every other in-shader path uses.
-    shader->set_uniform("projection_mode", m_bump_projection_mode);
+    shader->set_uniform("projection_mode", m_shaded_projection_mode);
-    shader->set_uniform("patch_center", m_bump_patch_center);
+    shader->set_uniform("patch_center", m_shaded_patch_center);
-    shader->set_uniform("patch_axis", m_bump_patch_axis);
+    shader->set_uniform("patch_axis", m_shaded_patch_axis);
 
     // The filament palette the mesh's per-triangle indices refer to. Count 0 means "no layer is
     // colouring", and the shader keeps the model's own colour for every fragment.
@@ -1416,13 +1415,13 @@ void GLGizmoTextureDisplacement::render_bump_preview_mesh()
     // matched on the CPU because the quantization is per fragment here.
     const GLTexture *color_tex = get_layer_color_texture(*layer);
     const int        palette_count =
-        (color_tex != nullptr) ? int(std::min(m_bump_preview_palette.size(), size_t(PALETTE_MAX_ENTRIES))) : 0;
+        (color_tex != nullptr) ? int(std::min(m_shaded_preview_palette.size(), size_t(PALETTE_MAX_ENTRIES))) : 0;
     shader->set_uniform("palette_count", palette_count);
     shader->set_uniform("has_color_tex", color_tex != nullptr);
     // A flat-colour image is matched against single filaments only, as the bake does.
     shader->set_uniform("pure_only", color_tex != nullptr && analyze_texture_detail(*layer).flat_colors);
     for (int i = 0; i < palette_count; ++i) {
-        const PaletteEntry &e   = m_bump_preview_palette[size_t(i)];
+        const PaletteEntry &e   = m_shaded_preview_palette[size_t(i)];
         const std::string   idx = "[" + std::to_string(i) + "]";
         shader->set_uniform(("palette_rgb" + idx).c_str(), e.rgb);
         shader->set_uniform(("palette_lab" + idx).c_str(), srgb_to_lab(e.rgb));
@@ -1434,7 +1433,7 @@ void GLGizmoTextureDisplacement::render_bump_preview_mesh()
     }
     // The filaments those indices refer to, and the interleave the shader resolves a mix with - the
     // same inputs make_mix_resolver() gets, so the preview shows the pattern that prints rather than
-    // the mix's smooth average colour. m_palette_filaments is what m_bump_preview_palette was built from.
+    // the mix's smooth average colour. m_palette_filaments is what m_shaded_preview_palette was built from.
     const int filament_count =
         (palette_count > 0) ? int(std::min(m_palette_filaments.size(), size_t(PALETTE_MAX_FILAMENTS))) : 0;
     shader->set_uniform("filament_count", filament_count);
@@ -1453,18 +1452,18 @@ void GLGizmoTextureDisplacement::render_bump_preview_mesh()
     }
     // The live UV-editor island drag rides this 2x3 affine (identity except mid-drag); only the flagged
     // island's vertices apply it, so a drag is a uniform update rather than a mesh rebuild.
-    const Eigen::Matrix<float, 2, 3> &d = m_bump_island_delta;
+    const Eigen::Matrix<float, 2, 3> &d = m_shaded_island_delta;
     shader->set_uniform("island_delta_lin", std::array<float, 4>{ d(0, 0), d(0, 1), d(1, 0), d(1, 1) });
     shader->set_uniform("island_delta_tr", Vec2f(d(0, 2), d(1, 2)));
-    m_bump_preview_glmodel.render();
+    m_shaded_preview_glmodel.render();
     glsafe(::glBindTexture(GL_TEXTURE_2D, 0));
     shader->stop_using();
 }
 
-bool GLGizmoTextureDisplacement::bump_preview_ready() const
+bool GLGizmoTextureDisplacement::shaded_preview_ready() const
 {
-    // Mirrors render_bump_preview_mesh()'s own preconditions. Kept as a separate query because the
+    // Mirrors render_shaded_preview_mesh()'s own preconditions. Kept as a separate query because the
-    // caller has to know whether the bump pass will draw *before* it hides the real volume for it.
+    // caller has to know whether the shaded pass will draw *before* it hides the real volume for it.
     if (m_c->selection_info() == nullptr || m_c->selection_info()->model_object() == nullptr)
         return false;
     if (texture_volume() == nullptr)
@@ -1472,12 +1471,12 @@ bool GLGizmoTextureDisplacement::bump_preview_ready() const
     const TextureDisplacementLayer *layer = active_layer();
     if (layer == nullptr || layer->empty())
         return false;
-    // The same texture render_bump_preview_mesh() will bind, not the panel thumbnail - the two are
+    // The same texture render_shaded_preview_mesh() will bind, not the panel thumbnail - the two are
     // separate caches and either can fail on its own.
     const GLTexture *tex = const_cast<GLGizmoTextureDisplacement *>(this)->get_layer_height_texture(*layer);
     if (tex == nullptr || tex->get_width() <= 0 || tex->get_height() <= 0)
         return false;
-    return wxGetApp().get_shader("texture_displacement_bump") != nullptr;
+    return wxGetApp().get_shader("texture_displacement_shaded") != nullptr;
 }
 
 // Appends a painted patch to an overlay, lifted onto the displaced surface where that has the base mesh's
@@ -1502,7 +1501,7 @@ void GLGizmoTextureDisplacement::rebuild_other_paint_overlay()
     // displaced positions it is lifted onto. Compared every frame, rebuilt only when it differs.
     std::string key;
     if (mv != nullptr) {
-        key = std::to_string(mv->id().id) + ":" + std::to_string(m_active_layer_slot) + (m_use_bump_preview ? ":b:" : ":t:") +
+        key = std::to_string(mv->id().id) + ":" + std::to_string(m_active_layer_slot) + (m_use_shaded_preview ? ":b:" : ":t:") +
               std::to_string(reinterpret_cast<uintptr_t>(m_preview_its.vertices.data())) + ":" +
               std::to_string(m_preview_its.vertices.size());
         for (const TextureDisplacementLayer &l : mv->texture_displacement_layers)
@@ -1517,7 +1516,7 @@ void GLGizmoTextureDisplacement::rebuild_other_paint_overlay()
         return;
 
     const std::vector<Vec3f> *displaced = nullptr;
-    if (!m_use_bump_preview && m_preview_its.vertices.size() == mv->mesh().its.vertices.size() &&
+    if (!m_use_shaded_preview && m_preview_its.vertices.size() == mv->mesh().its.vertices.size() &&
         !m_preview_its.vertices.empty())
         displaced = &m_preview_its.vertices;
 
@@ -1559,7 +1558,7 @@ void GLGizmoTextureDisplacement::rebuild_paint_overlay()
     // the brush split live past the end of that array and keep their flat position; they sit on the
     // patch boundary, where the displacement is smallest anyway.
     const std::vector<Vec3f> *displaced = nullptr;
-    if (!m_use_bump_preview && m_preview_its.vertices.size() == mv->mesh().its.vertices.size() &&
+    if (!m_use_shaded_preview && m_preview_its.vertices.size() == mv->mesh().its.vertices.size() &&
         !m_preview_its.vertices.empty())
         displaced = &m_preview_its.vertices;
 
@@ -1592,7 +1591,7 @@ void GLGizmoTextureDisplacement::render_paint_overlay(GLModel &overlay)
     shader->set_uniform("view_model_matrix", camera.get_view_matrix() * trafo_matrix);
     shader->set_uniform("projection_matrix", camera.get_projection_matrix());
     // Translucent, and pulled toward the camera so it wins the depth test against the coincident
-    // bump surface. Depth writes are off: this is a tint, and letting it own the depth buffer would
+    // shaded surface. Depth writes are off: this is a tint, and letting it own the depth buffer would
     // make the wireframe and seam overlays drawn after it fight with geometry that is not really
     // there. Blending is already enabled by render_painter_gizmo().
     glsafe(::glEnable(GL_POLYGON_OFFSET_FILL));
@@ -1703,7 +1702,7 @@ void GLGizmoTextureDisplacement::rebuild_uvcheck_mesh()
     m_uvcheck_uses_vertex_uv    = have_uvs;
     m_uvcheck_projection_mode   = have_uvs ? 0 :
                                       layer_projection_frame(patch, *layer, m_uvcheck_patch_center, m_uvcheck_patch_axis);
-    // Per corner as well, for the same reason the bump mesh takes them: under LSCM a seam vertex has a
+    // Per corner as well: under LSCM a seam vertex has a
     // different uv in each island it borders, so the shared-vertex form drew one triangle per face from
     // a neighbouring island's placement. Only the *drawing* needs this; the distortion metric below is
     // a per-vertex average by construction and keeps using `uv`.
@@ -1797,7 +1796,7 @@ void GLGizmoTextureDisplacement::render_uvcheck_mesh()
     const Matrix3d view_normal_matrix = camera.get_view_matrix().matrix().block(0, 0, 3, 3);
     shader->set_uniform("view_normal_matrix", view_normal_matrix);
     shader->set_uniform("volume_mirrored", trafo_matrix.matrix().determinant() < 0.0);
-    shader->set_uniform("tex_anchor", Vec3f(trafo_matrix.translation().cast<float>())); // see the bump shader
+    shader->set_uniform("tex_anchor", Vec3f(trafo_matrix.translation().cast<float>())); // see the preview shader
     shader->set_uniform("mode", m_uv_check_mode == UVCheckMode::Distortion ? 1 : 0);
     shader->set_uniform("checker_freq", 4.f); // squares per texture tile
     shader->set_uniform("tiling_scale", layer->tiling_scale);
@@ -1855,7 +1854,7 @@ void GLGizmoTextureDisplacement::rebuild_wireframe_overlay()
     if (its.indices.empty())
         return;
 
-    // Building from the base mesh (bump/paint mode); its topology only changes on bake/subdivide, and
+    // Building from the base mesh (shaded/paint mode); its topology only changes on bake/subdivide, and
     // this runs on every rebuild_preview(), so rebuild only when the vertex count actually changes.
     if (m_wireframe_overlay_glmodel.is_initialized() && m_wireframe_overlay_vcount == its.vertices.size())
         return;
@@ -1871,9 +1870,9 @@ void GLGizmoTextureDisplacement::refresh_wireframe()
     }
     // The wireframe has to sit on whatever mesh is actually on screen. In the true-displacement view
     // that is the raised preview geometry (m_preview_its) - drawing the flat base mesh's edges there
-    // leaves them buried inside the bumps, which is why the wireframe "didn't show in real mode". In
+    // leaves them buried inside the relief, which is why the wireframe "didn't show in real mode". In
-    // Fast (bump) mode or with nothing painted, the surface is the undisplaced base mesh.
+    // Fast (shaded) mode or with nothing painted, the surface is the undisplaced base mesh.
-    if (!m_use_bump_preview && !m_preview_its.indices.empty())
+    if (!m_use_shaded_preview && !m_preview_its.indices.empty())
         build_wireframe_from_its(m_preview_its);
     else
         rebuild_wireframe_overlay();
@@ -1907,13 +1906,13 @@ void GLGizmoTextureDisplacement::render_wireframe_overlay()
 
 void GLGizmoTextureDisplacement::rebuild_preview()
 {
-    // Bumped first: any in-flight job's result (captured generation from before this call) will
+    // Raised first: any in-flight job's result (captured generation from before this call) will
     // now compare unequal to m_preview_generation and be discarded when it completes, even if it
     // finishes after the job queued below - and, since the counter is shared with the worker, that
     // job also notices mid-run and aborts rather than computing a result nobody will use.
     m_preview_generation->fetch_add(1);
     update_uv_editor();
-    rebuild_bump_preview_mesh();
+    rebuild_shaded_preview_mesh();
     rebuild_paint_overlay();
     rebuild_uvcheck_mesh();
     rebuild_seam_overlay();
@@ -1939,7 +1938,7 @@ void GLGizmoTextureDisplacement::rebuild_preview()
     }
     // In Fast/paint modes the wireframe follows the base mesh and can be built now; the true-displacement
     // view's wireframe needs the displaced mesh, which only exists once the job below completes.
-    if (m_use_bump_preview) {
+    if (m_use_shaded_preview) {
         refresh_wireframe();
         // Fast view: the shader *is* the preview, and m_preview_glmodel is never drawn. Running the
         // full CPU displacement anyway - which is what happened on every stroke and slider release -
@@ -2040,7 +2039,7 @@ void GLGizmoTextureDisplacement::queue_preview_job()
             }
             if (m_preview_job_pending) {
                 m_preview_job_pending = false;
-                if (!m_use_bump_preview)
+                if (!m_use_shaded_preview)
                     queue_preview_job(); // no-ops if the gizmo has closed in the meantime
             }
             m_parent.set_as_dirty();
@@ -2310,12 +2309,12 @@ void GLGizmoTextureDisplacement::process_uv_commands()
 
 void GLGizmoTextureDisplacement::apply_view_mode(int mode)
 {
-    m_use_bump_preview = (mode == 1);
+    m_use_shaded_preview = (mode == 1);
     m_uv_check_mode    = (mode == 2) ? UVCheckMode::Checker :
                          (mode == 3) ? UVCheckMode::Distortion : UVCheckMode::None;
     rebuild_uvcheck_mesh();
-    if (m_use_bump_preview)
+    if (m_use_shaded_preview)
-        rebuild_bump_preview_mesh();
+        rebuild_shaded_preview_mesh();
     else
         // The Fast view skips the CPU displacement entirely (see rebuild_preview()), so leaving it means
         // m_preview_glmodel may be stale or absent - ask for it now.
@@ -2426,7 +2425,7 @@ void GLGizmoTextureDisplacement::run_uv_command(int cmd, float value)
     if (cmd == int(Command::SetBackground)) {
         // Height goes back to whichever of Normal / Fast was showing; Checker and Distortion are views of their own.
         const int background = std::clamp(int(std::lround(value)), 0, 2);
-        apply_view_mode(background == 1 ? 2 : background == 2 ? 3 : (m_use_bump_preview ? 1 : 0));
+        apply_view_mode(background == 1 ? 2 : background == 2 ? 3 : (m_use_shaded_preview ? 1 : 0));
         return;
     }
 
@@ -2838,10 +2837,10 @@ void GLGizmoTextureDisplacement::on_island_edited(int island, const Vec2f &offse
         m_island_move_set = is_move ? build_island_move_set(*layer, island) : std::vector<int>{ island };
         // Set up the GPU drag: bake the mesh once (via the dirty flag), which is also what flags the
         // moved islands' triangles. From then on the drag is a uniform update, no rebuild - see
-        // render_bump_preview_mesh().
+        // render_shaded_preview_mesh().
-        m_bump_active_chart = island;
+        m_shaded_active_chart = island;
-        m_bump_island_delta  = Eigen::Matrix<float, 2, 3>::Identity();
+        m_shaded_island_delta  = Eigen::Matrix<float, 2, 3>::Identity();
-        m_bump_preview_dirty = true;
+        m_shaded_preview_dirty = true;
     }
 
     // Apply the edit. A move goes to every island in the moved set (same offset -> they translate as
@@ -2865,10 +2864,10 @@ void GLGizmoTextureDisplacement::on_island_edited(int island, const Vec2f &offse
 
     if (finished) {
         m_island_drag_active = false;
-        m_bump_active_chart  = -1;
+        m_shaded_active_chart  = -1;
-        m_bump_active_face.clear();
+        m_shaded_active_face.clear();
         m_island_move_set.clear();
-        m_bump_island_delta  = Eigen::Matrix<float, 2, 3>::Identity();
+        m_shaded_island_delta  = Eigen::Matrix<float, 2, 3>::Identity();
         rebuild_preview(); // the real displaced geometry moved: recompute it once, at the end
     } else {
         const std::vector<Eigen::Matrix<float, 2, 3>> xf = uv_editor_island_transforms(*layer);
@@ -2879,15 +2878,15 @@ void GLGizmoTextureDisplacement::on_island_edited(int island, const Vec2f &offse
             uv_canvas->set_island_transforms(xf);
         }
         // Move the island on the model live through the shader's island_delta uniform - no mesh
-        // rebuild. delta = F_current * F_baked^-1 in final-uv space (the bump mesh bakes F_baked; the
+        // rebuild. delta = F_current * F_baked^-1 in final-uv space. 
-        // shader applies delta to the flagged island's uv). The one rebuild that bakes the flags is
+        // The one rebuild that bakes the flags is
         // scheduled at drag start above and consumed once per frame by render_painter_gizmo().
-        if (m_use_bump_preview && m_bump_active_chart == island && size_t(island) < xf.size()) {
+        if (m_use_shaded_preview && m_shaded_active_chart == island && size_t(island) < xf.size()) {
             Eigen::Matrix3f cur = Eigen::Matrix3f::Identity();
             cur.topRows<2>()    = xf[size_t(island)];
             Eigen::Matrix3f bak = Eigen::Matrix3f::Identity();
-            bak.topRows<2>()    = m_bump_baked_active_xf;
+            bak.topRows<2>()    = m_shaded_baked_active_xf;
-            m_bump_island_delta = (cur * bak.inverse()).topRows<2>();
+            m_shaded_island_delta = (cur * bak.inverse()).topRows<2>();
             m_parent.set_as_dirty();
         }
     }
@@ -3260,12 +3259,12 @@ void GLGizmoTextureDisplacement::update_model_object()
         updated |= facet.set(*m_triangle_selectors[idx]);
     }
 
-    // The fast (bump) preview reads the live selector, so it has to be rebuilt after any stroke that
+    // The fast (shaded) preview reads the live selector, so it has to be rebuilt after any stroke that
     // flushes here - not only when set() reports a change. Rebuilding it via rebuild_preview() below
     // is gated on `updated`, which misses e.g. the first paint into a slot; marking it dirty makes the
     // render loop (render_painter_gizmo) rebuild it next frame regardless. Without this, fast preview -
     // now the default view - stayed blank until a full reload (select-whole-model / reopen).
-    m_bump_preview_dirty = true;
+    m_shaded_preview_dirty = true;
 
     if (updated) {
         const ModelObjectPtrs &mos = wxGetApp().model().objects;
@@ -3337,7 +3336,7 @@ void GLGizmoTextureDisplacement::set_active_layer(int slot)
     // instead of leaving it pointing at the previous layer's (now stale) paint patch.
     if (m_adjust_texture_mode)
         update_adjust_anchor();
-    // Refresh every preview/overlay (bump, UV editor, seams, ...) for the newly active layer.
+    // Refresh every preview/overlay (shaded, UV editor, seams, ...) for the newly active layer.
     rebuild_preview();
 }
 
@@ -4166,7 +4165,7 @@ TextureColorSettings GLGizmoTextureDisplacement::color_settings_for(const ModelV
 
 const std::vector<GLGizmoTextureDisplacement::PaletteEntry> &GLGizmoTextureDisplacement::cached_palette()
 {
-    // Rebuilt only when the loaded filaments or the mixing setting actually change. The bump preview
+    // Rebuilt only when the loaded filaments or the mixing setting actually change. The shaded preview
     // rebuilds on every paint stroke and the subdivide preview on every slider frame, and filling the
     // quantizer's lookup cube for a 64-entry palette is tens of milliseconds - paying that per stroke
     // is the difference between painting that keeps up and painting that stutters.
@@ -4795,7 +4794,7 @@ GLTexture *GLGizmoTextureDisplacement::get_layer_thumbnail(const TextureDisplace
 
     // Reuses the already-decoded, already-cached grayscale pixels (see decode_height_texture()'s
     // own cache in TextureDisplacement.cpp) - only the gray-to-RGBA expansion and GPU upload below are
-    // new work. Rebuilt when the texture *or the smoothing* changes, so the fast/bump preview - which
+    // new work. Rebuilt when the texture *or the smoothing* changes, so the fast/shaded preview - which
     // samples this GPU texture directly - reflects the current smoothing rather than the raw image.
     std::unique_ptr<GLTexture> texture = upload_height_thumbnail(decode_height_texture(layer));
     if (!texture)
@@ -4831,7 +4830,7 @@ GLTexture *GLGizmoTextureDisplacement::get_layer_height_texture(const TextureDis
     if (layer.empty())
         return nullptr;
 
-    // One slot, not one per layer: the bump shader only ever shades the *active* layer, so a single
+    // One slot, not one per layer: the preview shader only ever shades the *active* layer, so a single
     // full-resolution upload is enough and the VRAM cost stays at one texture rather than eight.
     if (m_height_tex && m_height_tex_source == layer.image_data.get() && m_height_tex_smoothing == layer.smoothing)
         return m_height_tex.get();
@@ -5033,7 +5032,7 @@ void GLGizmoTextureDisplacement::show_debug_stage(int index)
     m_debug_stage = index;
     // Drawn through the ordinary true-displacement preview, so the Fast view - a shader trick over
     // the base mesh that never draws m_preview_glmodel - has to be left first.
-    m_use_bump_preview = false;
+    m_use_shaded_preview = false;
     m_preview_color_runs.clear();
     m_preview_glmodel.reset();
 
@@ -5667,9 +5666,9 @@ void GLGizmoTextureDisplacement::on_render_input_window(float x, float y, float
     }
 
     // ---- View: Normal / Fast / Checker / Distortion as one group, Wireframe on its own ----
-    // The underlying state stays m_use_bump_preview + m_uv_check_mode.
+    // The underlying state stays m_use_shaded_preview + m_uv_check_mode.
     {
-        const int cur_mode = m_use_bump_preview                               ? 1 :
+        const int cur_mode = m_use_shaded_preview                               ? 1 :
                              m_uv_check_mode == UVCheckMode::Checker    ? 2 :
                              m_uv_check_mode == UVCheckMode::Distortion ? 3 : 0;
         int  new_mode  = cur_mode;
@@ -5692,7 +5691,7 @@ void GLGizmoTextureDisplacement::on_render_input_window(float x, float y, float
             new_mode = 0;
         ImGui::SameLine(0.f, gap_s);
         if (icon_toggle(702, "texture_displacement_fast_preview.svg", cur_mode == 1, icon_md, _L("Fast"),
-                        _L("Fast - a bump-shaded approximation of the active layer only; quick to update, not exact")))
+                        _L("Fast - a shaded approximation of the active layer only; quick to update, not exact")))
             new_mode = 1;
         ImGui::SameLine(0.f, gap_s);
         if (icon_toggle(703, "texture_displacement_checker.svg", cur_mode == 2, icon_md, _L("Checker"),
@@ -6443,7 +6442,7 @@ void GLGizmoTextureDisplacement::on_render_input_window(float x, float y, float
             if (m_subdivide_feature) {
                 if (float_row("##subdiv_detail", _L("Detail"), &m_subdivide_detail_mm, 0.001f, 1.f, "%.3f mm", true, 0.f))
                     preview_live();
-                hover_tip(_u8L("How closely the mesh follows the texture's relief. Smaller captures finer bumps; "
+                hover_tip(_u8L("How closely the mesh follows the texture's relief. Smaller captures finer detail; "
                                "larger only chases the big features."));
                 if (float_row("##subdiv_min", _L("Min edge"), &m_subdivide_min_edge_mm, 0.001f, 20.f, "%.3f mm", true, 0.f))
                     preview_live();
@@ -6528,7 +6527,7 @@ void GLGizmoTextureDisplacement::on_render_input_window(float x, float y, float
                           _u8L("Refines the painted area to the target edge length and carries your paint onto "
                                "the finer mesh. The rest of the model is left as it is.") :
                           _u8L("Replaces the model's geometry with the subdivided mesh and clears any not-yet-baked "
-                               "paint on it (already-baked bumps are unaffected)."));
+                               "paint on it (already-baked relief is unaffected)."));
         }
 
         // Remesh: even out uneven triangle sizes (CGAL isotropic remeshing).
@@ -6569,7 +6568,7 @@ void GLGizmoTextureDisplacement::on_render_input_window(float x, float y, float
         hover_tip(_u8L("Rebuilds the whole model with triangles close to this edge length - splitting the big "
                        "ones and merging the small ones - so displacement has an even density to work with. "
                        "Replaces the geometry; your paint is carried onto the new triangles spatially, so it "
-                       "survives (already-baked bumps are kept too)."));
+                       "survives (already-baked relief is kept too)."));
 
         // Settings for the whole stack rather than one layer. Standard mode pins them instead of showing them.
         if (mv != nullptr) {
@@ -6751,7 +6750,7 @@ void GLGizmoTextureDisplacement::on_render_input_window(float x, float y, float
             }
             m_imgui->disabled_end();
             hover_tip(_u8L("Auto: the resolution follows the model's size and the budget is the standard "
-                           "750 k, the same defaults as bumpmesh.com. Untick to set them by hand."));
+                           "750 k. Untick to set them by hand."));
             ImGui::SameLine();
             ImGui::SetNextItemWidth(x0 + panel_w - ImGui::GetCursorPosX());
             float shown = auto_res ? rec.edge_mm : opts.v2_refine_mm;
@@ -6764,7 +6763,7 @@ void GLGizmoTextureDisplacement::on_render_input_window(float x, float y, float
             }
             m_imgui->disabled_end();
             if (auto_res && rec.edge_mm > 0.f)
-                hover_tip(Slic3r::format(_u8L("The model's diagonal / 250, as bumpmesh.com sets it. Budget %1% k."), rec.budget_k));
+                hover_tip(Slic3r::format(_u8L("The model's diagonal / 250. Budget %1% k."), rec.budget_k));
             else
                 hover_tip(_u8L("Triangle edge length the painted area is refined to before displacement. "
                                "Smaller carries finer texture detail and costs more triangles; the budget "

src/slic3r/GUI/Gizmos/GLGizmoTextureDisplacement.hpp

@@ -303,7 +303,7 @@ private:
     GLTexture *get_layer_thumbnail(const TextureDisplacementLayer &layer);
 
     // The same texture at full resolution, for the fast-preview shader. One slot, shared by whichever
-    // layer is active, because that is the only one the bump shader ever shades.
+    // layer is active, because that is the only one the preview shader ever shades.
     GLTexture *get_layer_height_texture(const TextureDisplacementLayer &layer);
     // The layer's colour texture for the fast preview's per-fragment quantization. Null when the
     // layer is not colouring or its texture is grayscale.
@@ -389,13 +389,13 @@ private:
     void render_preview_mesh();
 
     // Alternate, GPU-only preview: perturbs shading normals from the active layer's height texture
-    // (a classic bump map) instead of actually moving vertices, using the
+    // instead of actually moving vertices, using the resources/shaders/*/texture_displacement_shaded.*
-    // resources/shaders/*/texture_displacement_bump.* shader. Faster than the true-displacement
+    // shader. Faster than the true-displacement preview (no CPU meshing at all - just a per-vertex
-    // preview (no CPU meshing at all - just a per-vertex paint-weight buffer built at the same
+    // paint-weight buffer built at the same cadence as rebuild_preview()) but only shows the *active*
-    // cadence as rebuild_preview()) but only shows the *active* layer, and any bump is a shading
+    // layer, and the relief it shows is a shading illusion, not real geometry - "Bake" always produces
-    // illusion, not real geometry - "Bake" always produces the true, exact result either way.
+    // the true, exact result either way.
-    void rebuild_bump_preview_mesh();
+    void rebuild_shaded_preview_mesh();
-    void render_bump_preview_mesh();
+    void render_shaded_preview_mesh();
 
     // Feeds the active layer's painted patch + LSCM unwrap (if it's using that projection method)
     // into Plater's docked UV-editor pane and shows it, or hides the pane if the active layer
@@ -636,16 +636,16 @@ private:
     // mouse button driving the drag hasn't been released yet - see on_render_input_window().
     bool m_preview_params_dirty = false;
 
-    // See rebuild_bump_preview_mesh()/render_bump_preview_mesh(). On by default: it is the cheap,
+    // See rebuild_shaded_preview_mesh()/render_shaded_preview_mesh(). On by default: it is the cheap,
     // instant-updating preview, so it is the better first impression while painting. The true-
     // displacement view (a background CPU remesh) is one click away in the View row when the user
     // wants an exact look at what Bake will produce.
-    bool    m_use_bump_preview = true;
+    bool    m_use_shaded_preview = true;
-    // Set from the UV editor's per-move island edits instead of rebuilding the (potentially large) bump
+    // Set from the UV editor's per-move island edits instead of rebuilding the (potentially large) shaded
     // mesh synchronously inside that mouse handler - doing the rebuild there stalled both the UV pane
     // and the 3D view. The rebuild is instead coalesced to once per 3D frame (render_painter_gizmo).
-    bool    m_bump_preview_dirty = false;
+    bool    m_shaded_preview_dirty = false;
-    GLModel m_bump_preview_glmodel;
+    GLModel m_shaded_preview_glmodel;
 
     // Translucent tint over the active layer's painted triangles, drawn on top of whichever preview
     // is showing. The base painter's own opaque paint highlight (render_triangles()) cannot be used
@@ -662,7 +662,7 @@ private:
     void             rebuild_island_overlay(const std::vector<int> &selection);
     void             render_island_overlay();
     // Set on every paint event, cleared when the overlay is rebuilt in render_painter_gizmo(). Kept
-    // separate from m_bump_preview_dirty so a stroke refreshes only the small painted patch per frame,
+    // separate from m_shaded_preview_dirty so a stroke refreshes only the small painted patch per frame,
     bool    m_paint_overlay_dirty = false;
     void    rebuild_paint_overlay();
     void    render_paint_overlay(GLModel &overlay);
@@ -671,33 +671,33 @@ private:
     GLModel     m_other_paint_glmodel;
     std::string m_other_paint_key;
     void        rebuild_other_paint_overlay();
-    // Whether render_bump_preview_mesh() would actually draw something. Checked before the real volume
+    // Whether render_shaded_preview_mesh() would actually draw something. Checked before the real volume
-    // is hidden: with no layer, no texture or no shader the bump path draws nothing, and hiding the
+    // is hidden: with no layer, no texture or no shader the shaded path draws nothing, and hiding the
     // volume for it left the model invisible.
-    bool    bump_preview_ready() const;
+    bool    shaded_preview_ready() const;
-    // Whether the current bump mesh carries a precomputed per-vertex uv (LSCM) that the shader
+    // Whether the current displacement mesh carries a precomputed per-vertex uv (LSCM) that the shader
-    // should sample at directly, rather than projecting in-shader. Set by rebuild_bump_preview_mesh().
+    // should sample at directly, rather than projecting in-shader. Set by rebuild_shaded_preview_mesh().
-    bool    m_bump_preview_uses_vertex_uv = false;
+    bool    m_shaded_preview_uses_vertex_uv = false;
-    // The projection frame handed to the bump shader, captured when the mesh is built. Cylindrical and
+    // The projection frame handed to the preview shader, captured when the mesh is built. Cylindrical and
     // Spherical are reconstructed in the fragment shader (there is no per-vertex uv for them) and wrap
     // around the whole patch, which no fragment can work out for itself. See layer_projection_frame().
-    int   m_bump_projection_mode = 0;
+    int   m_shaded_projection_mode = 0;
-    Vec3f m_bump_patch_center    = Vec3f::Zero();
+    Vec3f m_shaded_patch_center    = Vec3f::Zero();
-    Vec3f m_bump_patch_axis      = Vec3f::UnitZ();
+    Vec3f m_shaded_patch_axis      = Vec3f::UnitZ();
     // The palette the fast preview's per-triangle filament indices were built against, captured when
     // the mesh was. Empty when the active layer is not colouring, which is what tells the shader to
     // fall back to the model's own colour. Held rather than re-read at draw time so the indices baked
     // into the mesh can never be resolved against a different set of filaments than they were computed
     // from - loading a filament mid-session would otherwise recolour a stale preview at random.
-    std::vector<PaletteEntry> m_bump_preview_palette;
+    std::vector<PaletteEntry> m_shaded_preview_palette;
 
-    // GPU island drag: while an island is dragged in the UV editor, the bump mesh is baked once (with
+    // GPU island drag: while an island is dragged in the UV editor, the displacement mesh is baked once (with
     // the dragged island's vertices flagged, v_normal.y = 1) and then moved purely through the shader's
     // island_delta uniform - one uniform update per mouse move, no rebuild - so it tracks the cursor
-    // as smoothly as Adjust placement. m_bump_active_chart is the dragged island (or -1);
+    // as smoothly as Adjust placement. m_shaded_active_chart is the dragged island (or -1);
-    // m_bump_active_face flags the dragged islands' *triangles*, indexed by painted-patch face;
+    // m_shaded_active_face flags the dragged islands' *triangles*, indexed by painted-patch face;
-    // m_bump_baked_active_xf is that island's placement baked into the current mesh, against which the
+    // m_shaded_baked_active_xf is that island's placement baked into the current mesh, against which the
-    // live delta is measured; m_bump_island_delta is the resulting final-uv-space affine handed to the
+    // live delta is measured; m_shaded_island_delta is the resulting final-uv-space affine handed to the
     // shader (identity except mid-drag).
     //
     // Per triangle rather than per vertex deliberately: a seam vertex belongs to every chart touching
@@ -705,13 +705,13 @@ private:
     // island_active is an interpolated varying, so those neighbouring triangles then had island_delta
     // applied too - dragging one island moved every adjacent island's texture while the editor, which
     // is per chart, correctly moved only the one. A triangle belongs to exactly one chart.
-    int                        m_bump_active_chart = -1;
+    int                        m_shaded_active_chart = -1;
-    std::vector<uint8_t>       m_bump_active_face;
+    std::vector<uint8_t>       m_shaded_active_face;
-    Eigen::Matrix<float, 2, 3> m_bump_baked_active_xf = Eigen::Matrix<float, 2, 3>::Identity();
+    Eigen::Matrix<float, 2, 3> m_shaded_baked_active_xf = Eigen::Matrix<float, 2, 3>::Identity();
-    Eigen::Matrix<float, 2, 3> m_bump_island_delta    = Eigen::Matrix<float, 2, 3>::Identity();
+    Eigen::Matrix<float, 2, 3> m_shaded_island_delta    = Eigen::Matrix<float, 2, 3>::Identity();
-    // Flags `charts`' triangles in m_bump_active_face, sized to `patch_face_count` (the painted patch
+    // Flags `charts`' triangles in m_shaded_active_face, sized to `patch_face_count` (the painted patch
-    // the bump mesh is being built from). Cleared if the unwrap carries no face map.
+    // the displacement mesh is being built from). Cleared if the unwrap carries no face map.
-    void                       compute_bump_active_faces(const std::vector<int> &charts, size_t patch_face_count);
+    void                       compute_shaded_active_faces(const std::vector<int> &charts, size_t patch_face_count);
 
     // The set of islands the current UV-editor drag moves together: the pane's multi-selection unioned
     // with each selected island's join group (see build_island_move_set()). Populated at drag start and
@@ -729,7 +729,7 @@ private:
     // Final per-vertex texture uv for the projections the shader can't reconstruct itself - LSCM (an
     // unwrap) and ViewProjected (a projector plane the shader doesn't know). One entry per patch/base
     // vertex, already through apply_uv_transform(). Empty for Triplanar/Cylindrical/Spherical, which
-    // the shader projects on its own. Shared by the bump preview and the UV-check overlay.
+    // the shader projects on its own. Shared by the shaded preview and the UV-check overlay.
     std::vector<Vec2f> compute_layer_vertex_uvs(const indexed_triangle_set &patch,
                                                 const TextureDisplacementLayer &layer) const;
     // The same, but three UVs per patch triangle (corner 0..2 of triangle i at 3i..3i+2). This is what
@@ -757,7 +757,7 @@ private:
     UVCheckMode m_uv_check_mode = UVCheckMode::None;
     GLModel     m_uvcheck_glmodel;
     bool        m_uvcheck_uses_vertex_uv = false;
-    // As m_bump_projection_mode and friends, for the Checker overlay.
+    // As m_shaded_projection_mode and friends, for the Checker overlay.
     int         m_uvcheck_projection_mode = 0;
     Vec3f       m_uvcheck_patch_center    = Vec3f::Zero();
     Vec3f       m_uvcheck_patch_axis      = Vec3f::UnitZ();
@@ -798,14 +798,14 @@ private:
     bool    m_wireframe_overlay = false;
     GLModel m_wireframe_overlay_glmodel;
     size_t  m_wireframe_overlay_vcount = 0; // topology signature, so it rebuilds only on a real change
-    void rebuild_wireframe_overlay();       // from the base mesh (bump/paint mode)
+    void rebuild_wireframe_overlay();       // from the base mesh (shaded/paint mode)
     void build_wireframe_from_its(const indexed_triangle_set &its); // from an explicit mesh, no early-out
     void refresh_wireframe();               // pick base vs displaced source for the current view
     void render_wireframe_overlay();
     // The displaced preview geometry the last preview job produced, kept so the wireframe overlay can be
     // drawn on the raised surface actually shown in the true-displacement view (#: "wireframe in real mode").
     indexed_triangle_set m_preview_its;
-    // Bumped on every rebuild_preview() call; a background TextureDisplacementPreviewJob's result
+    // Raised on every rebuild_preview() call; a background TextureDisplacementPreviewJob's result
     // is only applied if this hasn't moved on since the job was queued (see rebuild_preview()),
     // so a burst of edits can't have an earlier, now-stale job clobber a later one's result.
     //
@@ -831,7 +831,7 @@ private:
     // The smoothing each cached thumbnail was built at, so a smoothing change re-uploads it.
     std::array<float, TEXTURE_DISPLACEMENT_MAX_LAYERS>                      m_thumbnail_smoothing{};
 
-    // Full-resolution height texture for the bump shader, keyed the same way (see
+    // Full-resolution height texture for the preview shader, keyed the same way (see
     // get_layer_height_texture()). A smoothing change re-uploads it, so the fast preview shows the
     // blur the bake will apply.
     std::unique_ptr<GLTexture> m_height_tex;

tests/libslic3r/test_texture_displacement.cpp

@@ -694,10 +694,10 @@ TEST_CASE("TextureDisplacement: feature-adaptive subdivision follows curvature,
                      (its.vertices[t[0]].y() + its.vertices[t[1]].y() + its.vertices[t[2]].y()) / 3.f);
     };
 
-    SECTION("a sharp bump refines densely at its center and leaves flat corners coarse")
+    SECTION("a sharp hill refines densely at its center and leaves flat corners coarse")
     {
-        // A tight Gaussian bump at the sheet's center: strong curvature near (0.5, 0.5), flat far away.
+        // A tight Gaussian hill at the sheet's center: strong curvature near (0.5, 0.5), flat far away.
-        HeightFieldSampler bump = [](const Vec3f &p, const Vec3f &) {
+        HeightFieldSampler hill = [](const Vec3f &p, const Vec3f &) {
             const float r2 = (p.x() - 0.5f) * (p.x() - 0.5f) + (p.y() - 0.5f) * (p.y() - 0.5f);
             return 1.0f * std::exp(-r2 / 0.02f);
         };
@@ -706,12 +706,12 @@ TEST_CASE("TextureDisplacement: feature-adaptive subdivision follows curvature,
         // here - this isolates the *curvature* contribution (the grid already meets the baseline).
         std::vector<int>           source;
         const indexed_triangle_set out =
-            subdivide_mesh_adaptive(grid, region, /*max edge*/ 0.3f, 200000, &source, bump, /*tol*/ 0.02f,
+            subdivide_mesh_adaptive(grid, region, /*max edge*/ 0.3f, 200000, &source, hill, /*tol*/ 0.02f,
                                     /*min_edge*/ 0.01f);
 
-        CHECK(out.indices.size() > grid.indices.size()); // the bump forced real refinement
+        CHECK(out.indices.size() > grid.indices.size()); // the hill forced real refinement
 
-        // The largest triangle near the bump's center must be much smaller than the largest in a flat
+        // The largest triangle near the hill's center must be much smaller than the largest in a flat
         // corner - i.e. triangles went where the curvature is, not spread evenly.
         float near_max = 0.f, far_max = 0.f;
         for (const auto &t : out.indices) {
@@ -1140,9 +1140,9 @@ TEST_CASE("TextureDisplacement: the step cutter turns a stepped field into walls
 
 TEST_CASE("TextureDisplacement: the step cutter passes a smooth field through untouched", "[TextureDisplacement]")
 {
-    // A wide bump: its mid-level contour runs through the sheet, but nowhere is it a step, so there is
+    // A wide hill: its mid-level contour runs through the sheet, but nowhere is it a step, so there is
     // nothing to cut - refinement is the right tool for it.
-    const HeightFieldSampler   bump = [](const Vec3f &p, const Vec3f &) {
+    const HeightFieldSampler   hill = [](const Vec3f &p, const Vec3f &) {
         const float r2 = (p.x() - 3.f) * (p.x() - 3.f) + (p.y() - 3.f) * (p.y() - 3.f);
         return 0.4f * std::exp(-r2 / 3.f);
     };
@@ -1151,7 +1151,7 @@ TEST_CASE("TextureDisplacement: the step cutter passes a smooth field through un
 
     std::vector<int>           source;
     size_t                     cuts = 0;
-    const indexed_triangle_set out  = cut_mesh_at_steps(sheet, region, bump, 0.05f, 0.075f, 0.f, &source, &cuts);
+    const indexed_triangle_set out  = cut_mesh_at_steps(sheet, region, hill, 0.05f, 0.075f, 0.f, &source, &cuts);
 
     CHECK(cuts == 0);
     CHECK(out.indices.size() == sheet.indices.size());
@@ -1363,7 +1363,7 @@ TEST_CASE("TextureDisplacement: edge flips lay a stepped field's wall along the
 // Automatic resolution (v2 pipeline)
 // ---------------------------------------------------------------------------------------------
 
-TEST_CASE("TextureDisplacement: automatic resolution follows the model's size like bumpmesh.com", "[TextureDisplacement]")
+TEST_CASE("TextureDisplacement: automatic resolution follows the model's size", "[TextureDisplacement]")
 {
     // A 20 mm cube: diagonal 34.64 mm, so diagonal / 250 = 0.1386 mm, rounded up to 0.14.
     const indexed_triangle_set cube = its_make_cube(20.f, 20.f, 20.f);