Improved renderer to display quad

Cargo.lock

@@ -96,6 +96,26 @@ version = "3.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "37ccbd214614c6783386c1af30caf03192f17891059cecc394b4fb119e363de3"
 
+[[package]]
+name = "bytemuck"
+version = "1.10.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c53dfa917ec274df8ed3c572698f381a24eef2efba9492d797301b72b6db408a"
+dependencies = [
+ "bytemuck_derive",
+]
+
+[[package]]
+name = "bytemuck_derive"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "562e382481975bc61d11275ac5e62a19abd00b0547d99516a415336f183dcd0e"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "byteorder"
 version = "1.4.3"
@@ -117,6 +137,7 @@ name = "canvas"
 version = "0.1.0"
 dependencies = [
  "bitflags",
+ "bytemuck",
  "cgmath",
  "chrono",
  "fern",

Cargo.toml

@@ -6,6 +6,7 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+# general dependencies
 log = "^0.4.17"
 chrono = "^0.4.19"
 fern = { version = "^0.6.1", features = ["colored"] }
@@ -13,7 +14,11 @@ bitflags = "^1.3.2"
 cgmath = "^0.18.0"
 pollster = "^0.2.5"
 
+# surface creation
 winit = "^0.26.1"
 raw-window-handle = "^0.4.3"
 
+# gpu API
 wgpu = "^0.13.0"
+bytemuck = { version = "1.4", features = [ "derive" ] }
+

src/renderer.rs

@@ -17,6 +17,7 @@ pub struct WgpuRenderer {
     config: wgpu::SurfaceConfiguration,
     size: Size,
     render_pipeline: wgpu::RenderPipeline,
+    quad_mesh: GpuMesh,
 }
 
 impl WgpuRenderer {
@@ -62,24 +63,26 @@ impl WgpuRenderer {
 
         let render_pipeline = {
             let shader = device.create_shader_module(wgpu::ShaderModuleDescriptor {
-                label: Some("test shader"),
-                source: wgpu::ShaderSource::Wgsl(include_str!("shaders/test_shader.wgsl").into()),
+                label: Some("shape shader"),
+                source: wgpu::ShaderSource::Wgsl(include_str!("shaders/shape.wgsl").into()),
             });
 
             let render_pipeline_layout =
                 device.create_pipeline_layout(&wgpu::PipelineLayoutDescriptor {
-                    label: Some("test render pipeline layout"),
+                    label: Some("shape render pipeline layout"),
                     bind_group_layouts: &[],
                     push_constant_ranges: &[],
             });
 
             device.create_render_pipeline(&wgpu::RenderPipelineDescriptor {
-                label: Some("test render pipeline"),
+                label: Some("shape render pipeline"),
                 layout: Some(&render_pipeline_layout),
                 vertex: wgpu::VertexState {
                     module: &shader,
                     entry_point: "vs_main",
-                    buffers: &[],
+                    buffers: &[
+                        Vertex::desc(),
+                    ],
                 },
                 fragment: Some(wgpu::FragmentState {
                     module: &shader,
@@ -114,6 +117,8 @@ impl WgpuRenderer {
             })
         };
 
+        let quad_mesh = GpuMesh::create(&device, &QUAD);
+        
         Ok(Self {
             surface,
             device,
@@ -121,6 +126,7 @@ impl WgpuRenderer {
             config,
             size, 
             render_pipeline,
+            quad_mesh,
         })
     }
 
@@ -174,7 +180,10 @@ impl WgpuRenderer {
             });
 
             render_pass.set_pipeline(&self.render_pipeline);
-            render_pass.draw(0..3, 0..1);
+            render_pass.set_vertex_buffer(0, self.quad_mesh.vertex_buffer.slice(..));
+            render_pass.set_index_buffer(self.quad_mesh.index_buffer.slice(..), 
+                                         wgpu::IndexFormat::Uint16);
+            render_pass.draw_indexed(0..self.quad_mesh.index_number, 0, 0..1);
         }
 
         self.queue.submit(std::iter::once(encoder.finish()));
@@ -182,3 +191,78 @@ impl WgpuRenderer {
     }
 }
 
+struct GpuMesh {
+    vertex_buffer: wgpu::Buffer,
+    index_buffer: wgpu::Buffer,
+    index_number: u32,
+}
+
+impl GpuMesh {
+
+    pub fn create(device: &wgpu::Device, mesh: &Mesh) -> Self {
+        use wgpu::util::DeviceExt;
+
+        let vertex_buffer = device.create_buffer_init(
+            &wgpu::util::BufferInitDescriptor {
+                label: Some("Vertex Buffer"),
+                contents: bytemuck::cast_slice(mesh.vertices),
+                usage: wgpu::BufferUsages::VERTEX,
+            }
+        );
+
+        let index_buffer = device.create_buffer_init(
+            &wgpu::util::BufferInitDescriptor {
+                label: Some("Index Buffer"),
+                contents: bytemuck::cast_slice(mesh.indices),
+                usage: wgpu::BufferUsages::INDEX,
+            }
+        );
+
+        Self {
+            vertex_buffer,
+            index_buffer,
+            index_number: mesh.indices.len() as u32,
+        }
+    }
+}
+
+//--Renderer struct utils---------------------------------------------------------------------------
+#[repr(C)]
+#[derive(Copy, Clone, bytemuck::Pod, bytemuck::Zeroable)]
+struct Vertex {
+    pub position: [f32; 2],
+    pub color: [f32; 3],
+}
+
+// lib.rs
+impl Vertex {
+
+    const ATTRIBS: [wgpu::VertexAttribute; 2] =
+    wgpu::vertex_attr_array![0 => Float32x2, 1 => Float32x3];
+
+    fn desc<'a>() -> wgpu::VertexBufferLayout<'a> {
+        wgpu::VertexBufferLayout {
+            array_stride: std::mem::size_of::<Vertex>() as wgpu::BufferAddress,
+            step_mode: wgpu::VertexStepMode::Vertex,
+            attributes: &Self::ATTRIBS,
+        }
+    }
+}
+
+struct Mesh<'a> {
+    pub vertices: &'a[Vertex],
+    pub indices: &'a[u16],
+}
+
+const QUAD: Mesh<'static> = Mesh {
+    vertices: &[
+        Vertex { position: [0.0, 0.0], color: [1.0, 0.0, 0.0] },
+        Vertex { position: [1.0, 0.0], color: [0.0, 1.0, 0.0] },
+        Vertex { position: [1.0, 1.0], color: [0.0, 0.0, 1.0] },
+        Vertex { position: [0.0, 1.0], color: [0.5, 0.5, 0.5] },
+    ],
+    indices: &[
+        0, 1, 2,
+        0, 2, 3,
+    ],
+};

src/shaders/shape.wgsl

@@ -0,0 +1,28 @@
+// Vertex shader
+
+struct VertexInput {
+    @location(0) position: vec2<f32>,
+    @location(1) color: vec3<f32>,
+};
+
+struct VertexOutput {
+    @builtin(position) clip_position: vec4<f32>,
+    @location(0) color: vec3<f32>,
+};
+
+@vertex
+fn vs_main(model: VertexInput) -> VertexOutput {
+
+    var out: VertexOutput;
+    out.color = model.color;
+    out.clip_position = vec4<f32>(model.position, 0.0, 1.0);
+    return out;
+}
+
+// Fragment shader
+
+@fragment
+fn fs_main(in: VertexOutput) -> @location(0) vec4<f32> {
+    return vec4<f32>(in.color, 1.0);
+}
+