Port libvgcode/improved G-code viewer from PrusaSlicer 2.8.0 (#10735)

# Description

Fixes #6813 
Fixes #7782 
Fixes #6367

This is a port of libvgcode, OpenGL Core Profile (libvgcode requires OpenGL 3.2+), and probably other stuff I forgot from PrusaSlicer. libvgcode is also known as "Improved G-code Viewer" which was introduced in [PrusaSlicer 2.8.0](https://github.com/prusa3d/PrusaSlicer/releases/tag/version_2.8.0-alpha5). It significantly improves performance of the G-code preview and allows displaying the actual speed and volumetric flow rate.

## TODO

- [x] Make the sliders work properly again
- [x] Make view type selection work
- [x] Fix toggling of feature type visibility
- [x] Expose actual speed/actual flow view types
- [x] Fix display of G2/G3 arcs
- [x] Wire up actual speed graph widgets
- [x] Fix painter gizmos
- [x] Fix crash when selecting filament view type on Windows
- [ ] Figure out display color management (#10827)
- [x] Fix incorrect rendering of small area flow compensation (or any extrusions with varying flow)
- [ ] Localization
- [ ] Testing
- [ ] Code cleanup, performance optimization

## Removed functionality

Some functionality is not supported by libvgcode:

- Toggling visibility of tools
- Toggling visibility of colors in color print view
- Support for systems with OpenGL <3.2
- Bambu's implementation of G2/G3 arcs was replaced with PrusaSlicer's implementation

# Screenshots/Recordings/Graphs

https://github.com/user-attachments/assets/c1413a82-3058-4541-b96c-3d5f7cdef174

<details>
<summary>Outdated Stuff</summary>

https://github.com/user-attachments/assets/ca172ef4-0828-4d21-8768-b08a4132c9ab

<img width="1611" height="1145" alt="image" src="https://github.com/user-attachments/assets/5e0d04ff-8046-4636-a08a-cdedc60303bc" />
</details>

## Tests

- [x] Normally sliced G-code
- [ ] G-code viewer mode
- [x] Arc fitting enabled
- [x] Spiral Z-hops
- [x] Multi-extruder/multi-color
- [x] Vase mode
- [x] Skirt/brim
- [x] Supports
- [ ] Support transition (whatever this is)
- [x] Painter gizmos
- [x] Measurement gizmo
- [x] Move/rotate/scale gizmos
- [x] H2D/H2S support (oh no)
- [ ] Windows
- [x] macOS
- [ ] Linux

resources/images/horizontal_hide.svg

@@ -0,0 +1,46 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<!-- Generator: Adobe Illustrator 24.0.0, SVG Export Plug-In . SVG Version: 6.00 Build 0)  -->
+
+<svg
+   version="1.0"
+   id="Layer_1"
+   x="0px"
+   y="0px"
+   viewBox="0 0 16 16"
+   enable-background="new 0 0 16 16"
+   xml:space="preserve"
+   sodipodi:docname="hide_horizontal.svg"
+   inkscape:version="1.1 (c68e22c387, 2021-05-23)"
+   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
+   xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:svg="http://www.w3.org/2000/svg"><defs
+   id="defs945">
+	
+
+		
+	</defs><sodipodi:namedview
+   id="namedview943"
+   pagecolor="#505050"
+   bordercolor="#eeeeee"
+   borderopacity="1"
+   inkscape:pageshadow="0"
+   inkscape:pageopacity="0"
+   inkscape:pagecheckerboard="0"
+   showgrid="false"
+   inkscape:zoom="50.75"
+   inkscape:cx="7.9901478"
+   inkscape:cy="8.0098522"
+   inkscape:window-width="1920"
+   inkscape:window-height="1001"
+   inkscape:window-x="3191"
+   inkscape:window-y="-9"
+   inkscape:window-maximized="1"
+   inkscape:current-layer="Layer_1" />
+<polygon
+   fill="#009688"
+   points="1,8 1,11 8,16 15,11 15,8 "
+   style="stroke:none;stroke-width:1"
+   id="polygon937"
+   transform="translate(0,-4)" />
+</svg>

resources/images/horizontal_show.svg

@@ -0,0 +1,46 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<!-- Generator: Adobe Illustrator 24.0.0, SVG Export Plug-In . SVG Version: 6.00 Build 0)  -->
+
+<svg
+   version="1.0"
+   id="Layer_1"
+   x="0px"
+   y="0px"
+   viewBox="0 0 16 16"
+   enable-background="new 0 0 16 16"
+   xml:space="preserve"
+   sodipodi:docname="show_horizontal.svg"
+   inkscape:version="1.1 (c68e22c387, 2021-05-23)"
+   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
+   xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:svg="http://www.w3.org/2000/svg"><defs
+   id="defs1127">
+	
+
+		
+	</defs><sodipodi:namedview
+   id="namedview1125"
+   pagecolor="#505050"
+   bordercolor="#eeeeee"
+   borderopacity="1"
+   inkscape:pageshadow="0"
+   inkscape:pageopacity="0"
+   inkscape:pagecheckerboard="0"
+   showgrid="false"
+   inkscape:zoom="50.75"
+   inkscape:cx="7.9901478"
+   inkscape:cy="8.0098522"
+   inkscape:window-width="1920"
+   inkscape:window-height="1001"
+   inkscape:window-x="3191"
+   inkscape:window-y="-9"
+   inkscape:window-maximized="1"
+   inkscape:current-layer="Layer_1" />
+<polygon
+   fill="#009688"
+   points="15,7 15,5 8,0 1,5 1,7 1,8 15,8 "
+   style="stroke:none;stroke-width:1"
+   id="polygon1119"
+   transform="translate(0,4)" />
+</svg>

resources/shaders/140/background.fs

@@ -5,7 +5,9 @@ uniform vec4 bottom_color;
 
 in vec2 tex_coord;
 
+out vec4 out_color;
+
 void main()
 {
-    gl_FragColor = mix(bottom_color, top_color, tex_coord.y);
+    out_color = mix(bottom_color, top_color, tex_coord.y);
 }

resources/shaders/140/dashed_thick_lines.fs

@@ -0,0 +1,34 @@
+#version 150
+
+// see as reference: https://github.com/mhalber/Lines/blob/master/geometry_shader_lines.h
+//                   https://stackoverflow.com/questions/52928678/dashed-line-in-opengl3
+
+const float aa_radius = 0.5;
+
+uniform float dash_size;
+uniform float gap_size;
+uniform vec4 uniform_color;
+
+in float line_width;
+// x = v tex coord, y = s coord
+in vec2 seg_params;
+
+out vec4 out_color;
+
+void main()
+{
+	float inv_stride = 1.0 / (dash_size + gap_size);
+    if (gap_size > 0.0 && fract(seg_params.y * inv_stride) > dash_size * inv_stride)
+        discard;
+		
+	// We render a quad that is fattened by r, giving total width of the line to be w+r. We want smoothing to happen
+	// around w, so that the edge is properly smoothed out. As such, in the smoothstep function we have:
+	// Far edge   : 1.0                                          = (w+r) / (w+r)
+	// Close edge : 1.0 - (2r / (w+r)) = (w+r)/(w+r) - 2r/(w+r)) = (w-r) / (w+r)
+	// This way the smoothing is centered around 'w'.
+
+	out_color = uniform_color;
+	float inv_line_width = 1.0 / line_width;
+	float aa = 1.0 - smoothstep(1.0 - (2.0 * aa_radius * inv_line_width),  1.0, abs(seg_params.x * inv_line_width));
+	out_color.a *= aa;
+}

resources/shaders/140/dashed_thick_lines.gs

@@ -0,0 +1,50 @@
+#version 150
+
+// see as reference: https://github.com/mhalber/Lines/blob/master/geometry_shader_lines.h
+//                   https://stackoverflow.com/questions/52928678/dashed-line-in-opengl3
+
+layout(lines) in;
+layout(triangle_strip, max_vertices = 4) out;
+
+const float aa_radius = 0.5;
+
+uniform vec2 viewport_size;
+uniform float width;
+
+in float coord_s[];
+
+out float line_width;
+// x = v tex coord, y = s coord
+out vec2 seg_params;
+
+void main()
+{
+	vec2 ndc_0 = gl_in[0].gl_Position.xy / gl_in[0].gl_Position.w;
+	vec2 ndc_1 = gl_in[1].gl_Position.xy / gl_in[1].gl_Position.w;
+
+	vec2 dir = normalize((ndc_1 - ndc_0) * viewport_size);
+	vec2 normal_dir = vec2(-dir.y, dir.x);
+
+	line_width  = max(1.0, width) + 2.0 * aa_radius;
+	float half_line_width  = 0.5 * line_width;
+	
+	vec2 normal = vec2(line_width / viewport_size[0], line_width / viewport_size[1]) * normal_dir;
+
+	seg_params = vec2(-half_line_width, coord_s[0]);
+	gl_Position = vec4((ndc_0 + normal) * gl_in[0].gl_Position.w, gl_in[0].gl_Position.zw);
+	EmitVertex();
+
+	seg_params = vec2(-half_line_width, coord_s[0]);
+	gl_Position = vec4((ndc_0 - normal) * gl_in[0].gl_Position.w, gl_in[0].gl_Position.zw);
+	EmitVertex();
+
+	seg_params = vec2(half_line_width, coord_s[1]);
+	gl_Position = vec4((ndc_1 + normal) * gl_in[1].gl_Position.w, gl_in[1].gl_Position.zw);
+	EmitVertex();
+
+	seg_params = vec2(half_line_width, coord_s[1]);
+	gl_Position = vec4((ndc_1 - normal) * gl_in[1].gl_Position.w, gl_in[1].gl_Position.zw);
+	EmitVertex();
+
+	EndPrimitive();
+}

resources/shaders/140/dashed_thick_lines.vs

@@ -0,0 +1,18 @@
+#version 150
+
+// see as reference: https://github.com/mhalber/Lines/blob/master/geometry_shader_lines.h
+//                   https://stackoverflow.com/questions/52928678/dashed-line-in-opengl3
+
+uniform mat4 view_model_matrix;
+uniform mat4 projection_matrix;
+
+// v_position.w = coordinate along the line
+in vec4 v_position;
+
+out float coord_s;
+
+void main()
+{
+	coord_s = v_position.w;
+    gl_Position = projection_matrix * view_model_matrix * vec4(v_position.xyz, 1.0);
+}

resources/shaders/140/flat.fs

@@ -2,7 +2,9 @@
 
 uniform vec4 uniform_color;
 
+out vec4 out_color;
+
 void main()
 {
-    gl_FragColor = uniform_color;
+    out_color = uniform_color;
 }

resources/shaders/140/flat_texture.fs

@@ -4,7 +4,9 @@ uniform sampler2D uniform_texture;
 
 in vec2 tex_coord;
 
+out vec4 out_color;
+
 void main()
 {
-    gl_FragColor = texture(uniform_texture, tex_coord);
+    out_color = texture(uniform_texture, tex_coord);
 }

resources/shaders/140/gouraud_light.fs

@@ -6,7 +6,9 @@ uniform float emission_factor;
 // x = tainted, y = specular;
 in vec2 intensity;
 
+out vec4 out_color;
+
 void main()
 {
-    gl_FragColor = vec4(vec3(intensity.y) + uniform_color.rgb * (intensity.x + emission_factor), uniform_color.a);
+    out_color = vec4(vec3(intensity.y) + uniform_color.rgb * (intensity.x + emission_factor), uniform_color.a);
 }

resources/shaders/140/gouraud_light_instanced.fs

@@ -6,7 +6,9 @@ uniform float emission_factor;
 // x = tainted, y = specular;
 in vec2 intensity;
 
+out vec4 out_color;
+
 void main()
 {
-    gl_FragColor = vec4(vec3(intensity.y) + uniform_color.rgb * (intensity.x + emission_factor), uniform_color.a);
+    out_color = vec4(vec3(intensity.y) + uniform_color.rgb * (intensity.x + emission_factor), uniform_color.a);
 }

resources/shaders/140/hotbed.fs

@@ -0,0 +1,46 @@
+#version 140
+
+const vec3 ZERO = vec3(0.0, 0.0, 0.0);
+const vec3 WHITE = vec3(1.0, 1.0, 1.0);
+struct PrintVolumeDetection
+{
+	// 0 = rectangle, 1 = circle, 2 = custom, 3 = invalid
+	int type;
+    // type = 0 (rectangle):
+    // x = min.x, y = min.y, z = max.x, w = max.y
+    // type = 1 (circle):
+    // x = center.x, y = center.y, z = radius
+	vec4 xy_data;
+    // x = min z, y = max z
+	vec2 z_data;
+};
+
+uniform vec4 uniform_color;
+uniform float emission_factor;
+uniform PrintVolumeDetection print_volume;
+// x = diffuse, y = specular;
+in vec2 intensity;
+in vec4 world_pos;
+
+out vec4 out_color;
+
+void main()
+{
+    vec3  color = uniform_color.rgb;
+    float alpha = uniform_color.a;
+	// if the fragment is outside the print volume -> use darker color
+    vec3 pv_check_min = ZERO;
+    vec3 pv_check_max = ZERO;
+    if (print_volume.type == 0) {// rectangle
+        pv_check_min = world_pos.xyz - vec3(print_volume.xy_data.x, print_volume.xy_data.y, print_volume.z_data.x);
+        pv_check_max = world_pos.xyz - vec3(print_volume.xy_data.z, print_volume.xy_data.w, print_volume.z_data.y);
+    }
+    else if (print_volume.type == 1) {// circle
+        float delta_radius = print_volume.xy_data.z - distance(world_pos.xy, print_volume.xy_data.xy);
+        pv_check_min = vec3(delta_radius, 0.0, world_pos.z - print_volume.z_data.x);
+        pv_check_max = vec3(0.0, 0.0, world_pos.z - print_volume.z_data.y);
+    }
+    color = (any(lessThan(pv_check_min, ZERO)) || any(greaterThan(pv_check_max, ZERO))) ? mix(color, WHITE, 0.3333) : color;
+	//out_color = vec4(vec3(intensity.y) + color * intensity.x, alpha);
+	out_color = vec4(vec3(intensity.y) + color * (intensity.x + emission_factor), alpha);
+}

resources/shaders/140/hotbed.vs

@@ -0,0 +1,47 @@
+#version 140
+
+#define INTENSITY_CORRECTION 0.6
+
+// normalized values for (-0.6/1.31, 0.6/1.31, 1./1.31)
+const vec3 LIGHT_TOP_DIR = vec3(-0.4574957, 0.4574957, 0.7624929);
+#define LIGHT_TOP_DIFFUSE    (0.8 * INTENSITY_CORRECTION)
+#define LIGHT_TOP_SPECULAR   (0.125 * INTENSITY_CORRECTION)
+#define LIGHT_TOP_SHININESS  20.0
+
+// normalized values for (1./1.43, 0.2/1.43, 1./1.43)
+const vec3 LIGHT_FRONT_DIR = vec3(0.6985074, 0.1397015, 0.6985074);
+#define LIGHT_FRONT_DIFFUSE  (0.3 * INTENSITY_CORRECTION)
+
+#define INTENSITY_AMBIENT    0.3
+
+uniform mat4 view_model_matrix;
+uniform mat4 projection_matrix;
+uniform mat3 view_normal_matrix;
+uniform mat4 volume_world_matrix;
+
+in vec3 v_position;
+in vec3 v_normal;
+
+// x = tainted, y = specular;
+out vec2 intensity;
+out vec4 world_pos;
+void main()
+{
+    // First transform the normal into camera space and normalize the result.
+    vec3 normal = normalize(view_normal_matrix * v_normal);
+
+    // Compute the cos of the angle between the normal and lights direction. The light is directional so the direction is constant for every vertex.
+    // Since these two are normalized the cosine is the dot product. We also need to clamp the result to the [0,1] range.
+    float NdotL = max(dot(normal, LIGHT_TOP_DIR), 0.0);
+
+    intensity.x = INTENSITY_AMBIENT + NdotL * LIGHT_TOP_DIFFUSE;
+    world_pos = volume_world_matrix * vec4(v_position, 1.0);
+    vec4 position = view_model_matrix * vec4(v_position, 1.0);
+    intensity.y = LIGHT_TOP_SPECULAR * pow(max(dot(-normalize(position.xyz), reflect(-LIGHT_TOP_DIR, normal)), 0.0), LIGHT_TOP_SHININESS);
+
+    // Perform the same lighting calculation for the 2nd light source (no specular applied).
+    NdotL = max(dot(normal, LIGHT_FRONT_DIR), 0.0);
+    intensity.x += NdotL * LIGHT_FRONT_DIFFUSE;
+
+    gl_Position = projection_matrix * position;
+}

resources/shaders/140/imgui.fs

@@ -5,7 +5,9 @@ uniform sampler2D Texture;
 in vec2 Frag_UV;
 in vec4 Frag_Color;
 
+out vec4 out_color;
+
 void main()
 {
-	gl_FragColor = Frag_Color * texture(Texture, Frag_UV.st);
+	out_color = Frag_Color * texture(Texture, Frag_UV.st);
 }

resources/shaders/140/mm_contour.fs

@@ -2,7 +2,9 @@
 
 uniform vec4 uniform_color;
 
+out vec4 out_color;
+
 void main()
 {
-    gl_FragColor = uniform_color;
+    out_color = uniform_color;
 }

resources/shaders/140/thumbnail.fs

@@ -9,13 +9,15 @@ in vec2 intensity;
 //varying float drop;
 in vec4 world_pos;
 
+out vec4 out_color;
+
 void main()
 {
     if (world_pos.z < 0.0)
         discard;
     if(ban_light){
-       gl_FragColor = uniform_color;
+       out_color = uniform_color;
     } else{
-       gl_FragColor = vec4(vec3(intensity.y) + uniform_color.rgb * (intensity.x + emission_factor), uniform_color.a);
+       out_color = vec4(vec3(intensity.y) + uniform_color.rgb * (intensity.x + emission_factor), uniform_color.a);
     }
 }

resources/shaders/140/variable_layer_height.fs

@@ -15,6 +15,8 @@ in vec2 intensity;
 
 in float object_z;
 
+out vec4 out_color;
+
 void main()
 {
     float object_z_row = z_to_texture_row * object_z;
@@ -37,5 +39,5 @@ void main()
         color = mix(texture(z_texture, vec2(z_texture_col, z_texture_row_to_normalized * (z_texture_row + 0.5    )), -10000.),
                     texture(z_texture, vec2(z_texture_col, z_texture_row_to_normalized * (z_texture_row * 2. + 1.)),  10000.), lod);            
     // Mix the final color.
-    gl_FragColor = vec4(vec3(intensity.y), 1.0) +  intensity.x * mix(color, vec4(1.0, 1.0, 0.0, 1.0), z_blend);
+    out_color = vec4(vec3(intensity.y), 1.0) +  intensity.x * mix(color, vec4(1.0, 1.0, 0.0, 1.0), z_blend);
 }