dave: switch to use standard vertex/index buffers

Fixes: https://github.com/damus-io/notedeck/issues/902 Signed-off-by: William Casarin <jb55@jb55.com>
2025-08-03 18:27:44 -07:00
parent 0dda26791a
commit 571bf35109
5 changed files with 201 additions and 155 deletions
--- a/crates/notedeck_dave/src/mesh.rs
+++ b/crates/notedeck_dave/src/mesh.rs
@@ -0,0 +1,71 @@
+use eframe::egui_wgpu::wgpu;
+
+#[repr(C)]
+#[derive(Clone, Copy, bytemuck::Pod, bytemuck::Zeroable)]
+pub struct Vertex {
+    pos: [f32; 3],
+    normal: [f32; 3],
+}
+
+impl Vertex {
+    pub const ATTRS: [wgpu::VertexAttribute; 2] = wgpu::vertex_attr_array![
+        0 => Float32x3, // position
+        1 => Float32x3  // normal
+    ];
+    pub const LAYOUT: wgpu::VertexBufferLayout<'static> = wgpu::VertexBufferLayout {
+        array_stride: std::mem::size_of::<Vertex>() as wgpu::BufferAddress,
+        step_mode: wgpu::VertexStepMode::Vertex,
+        attributes: &Self::ATTRS,
+    };
+}
+
+// 6 faces * 4 verts. Each face has a constant normal.
+#[rustfmt::skip]
+pub const CUBE_VERTICES: [Vertex; 24] = [
+    // -Z (back)
+    Vertex { pos: [-0.5,-0.5,-0.5], normal: [0.0, 0.0,-1.0] },
+    Vertex { pos: [ 0.5,-0.5,-0.5], normal: [0.0, 0.0,-1.0] },
+    Vertex { pos: [ 0.5, 0.5,-0.5], normal: [0.0, 0.0,-1.0] },
+    Vertex { pos: [-0.5, 0.5,-0.5], normal: [0.0, 0.0,-1.0] },
+
+    // +Z (front)
+    Vertex { pos: [-0.5,-0.5, 0.5], normal: [0.0, 0.0, 1.0] },
+    Vertex { pos: [ 0.5,-0.5, 0.5], normal: [0.0, 0.0, 1.0] },
+    Vertex { pos: [ 0.5, 0.5, 0.5], normal: [0.0, 0.0, 1.0] },
+    Vertex { pos: [-0.5, 0.5, 0.5], normal: [0.0, 0.0, 1.0] },
+
+    // -X (left)
+    Vertex { pos: [-0.5,-0.5,-0.5], normal: [-1.0, 0.0, 0.0] },
+    Vertex { pos: [-0.5, 0.5,-0.5], normal: [-1.0, 0.0, 0.0] },
+    Vertex { pos: [-0.5, 0.5, 0.5], normal: [-1.0, 0.0, 0.0] },
+    Vertex { pos: [-0.5,-0.5, 0.5], normal: [-1.0, 0.0, 0.0] },
+
+    // +X (right)
+    Vertex { pos: [ 0.5,-0.5,-0.5], normal: [1.0, 0.0, 0.0] },
+    Vertex { pos: [ 0.5, 0.5,-0.5], normal: [1.0, 0.0, 0.0] },
+    Vertex { pos: [ 0.5, 0.5, 0.5], normal: [1.0, 0.0, 0.0] },
+    Vertex { pos: [ 0.5,-0.5, 0.5], normal: [1.0, 0.0, 0.0] },
+
+    // -Y (bottom)
+    Vertex { pos: [-0.5,-0.5,-0.5], normal: [0.0,-1.0, 0.0] },
+    Vertex { pos: [-0.5,-0.5, 0.5], normal: [0.0,-1.0, 0.0] },
+    Vertex { pos: [ 0.5,-0.5, 0.5], normal: [0.0,-1.0, 0.0] },
+    Vertex { pos: [ 0.5,-0.5,-0.5], normal: [0.0,-1.0, 0.0] },
+
+    // +Y (top)
+    Vertex { pos: [-0.5, 0.5,-0.5], normal: [0.0, 1.0, 0.0] },
+    Vertex { pos: [-0.5, 0.5, 0.5], normal: [0.0, 1.0, 0.0] },
+    Vertex { pos: [ 0.5, 0.5, 0.5], normal: [0.0, 1.0, 0.0] },
+    Vertex { pos: [ 0.5, 0.5,-0.5], normal: [0.0, 1.0, 0.0] },
+];
+
+// 6 faces * 2 triangles * 3 indices — all CCW when viewed from the outside
+pub const CUBE_INDICES: [u16; 36] = [
+    // -Z (back)   normal (0, 0,-1)
+    0, 3, 2, 0, 2, 1, // +Z (front)  normal (0, 0, 1)
+    4, 5, 6, 4, 6, 7, // -X (left)   normal (-1,0, 0)
+    8, 11, 10, 8, 10, 9, // +X (right)  normal ( 1,0, 0)
+    12, 13, 14, 12, 14, 15, // -Y (bottom) normal (0,-1, 0)
+    16, 18, 17, 16, 19, 18, // +Y (top)    normal (0, 1, 0)
+    20, 21, 22, 20, 22, 23,
+];