Random triangle color render mode

TODO.md

@@ -94,4 +94,4 @@
 - [x] Fix requiring viewport to be visible to render preview image
 - [x] Visulize mesh outside of bounging box
 - [ ] Save panel layout
-- [ ] Random triangle color render mode
+- [x] Random triangle color render mode

mslicer/src/render/pipelines/model.rs

@@ -43,6 +43,7 @@ struct ModelUniforms {
 #[repr(u8)]
 pub enum RenderStyle {
     Normals,
+    RandomTriangle,
     Rended,
 }
 
@@ -187,9 +188,16 @@ impl ModelPipeline {
 }
 
 impl RenderStyle {
+    pub const ALL: [RenderStyle; 3] = [
+        RenderStyle::Normals,
+        RenderStyle::RandomTriangle,
+        RenderStyle::Rended,
+    ];
+
     pub fn name(&self) -> &'static str {
         match self {
             RenderStyle::Normals => "Normals",
+            RenderStyle::RandomTriangle => "Triangles",
             RenderStyle::Rended => "Rended",
         }
     }

mslicer/src/shaders/model.wgsl

@@ -11,15 +11,14 @@ struct Context {
 }
 
 struct VertexInput {
-    @location(0)
-    position: vec4<f32>
+    @builtin(vertex_index) index: u32,
+    @location(0) position: vec4<f32>
 }
 
 struct VertexOutput {
-    @builtin(position)
-    position: vec4<f32>,
-    @location(1)
-    world_position: vec3<f32>
+    @builtin(position) position: vec4<f32>,
+    @location(1) world_position: vec3<f32>,
+    @location(2) vertex_index: u32
 };
 
 @vertex
@@ -27,6 +26,7 @@ fn vert(in: VertexInput) -> VertexOutput {
     var out: VertexOutput;
     out.position = context.transform * in.position;
     out.world_position = (context.model_transform * in.position).xyz;
+    out.vertex_index = in.index;
     return out;
 }
 
@@ -42,6 +42,9 @@ fn frag(in: VertexOutput) -> @location(0) vec4<f32> {
 
     if context.render_style == 0 {
         return vec4<f32>(normal, 1.0);
+    } else if context.render_style == 1 {
+        seed = in.vertex_index;
+        return vec4f(rand(), rand(), rand(), 1.0);
     } else {
         let camera_direction = normalize(context.camera_position + context.camera_target);
 
@@ -61,3 +64,11 @@ fn outside_build_volume(pos: vec3<f32>) -> bool {
         || pos.y < -build.y || pos.y > build.y
         || pos.z < 0.0 || pos.x > context.build_volume.z;
 }
+
+var<private> seed: u32 = 0u;
+
+fn rand() -> f32 {
+    seed = seed * 747796405u + 2891336453u;
+    let f = f32(seed >> 9u) / f32(1u << 23u);
+    return fract(f);
+}

mslicer/src/windows/workspace.rs

@@ -35,12 +35,9 @@ pub fn ui(app: &mut App, ui: &mut Ui, _ctx: &Context) {
     ComboBox::new("render_style", "Render Style")
         .selected_text(app.config.render_style.name())
         .show_ui(ui, |ui| {
-            ui.selectable_value(
-                &mut app.config.render_style,
-                RenderStyle::Normals,
-                "Normals",
-            );
-            ui.selectable_value(&mut app.config.render_style, RenderStyle::Rended, "Rended");
+            for style in RenderStyle::ALL {
+                ui.selectable_value(&mut app.config.render_style, style, style.name());
+            }
         });
 
     ComboBox::new("theme", "Theme")