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.

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)