[oden] Input coordinates are pixel coordinates

src/lib.rs

@@ -1,4 +1,5 @@
 use bytemuck;
+use wgpu::util::DeviceExt;
 use winit::{
     event::*,
     event_loop::{ControlFlow, EventLoop},
@@ -38,6 +39,20 @@ impl Vertex {
     }
 }
 
+#[repr(C)]
+#[derive(Copy, Clone, Debug, bytemuck::Pod, bytemuck::Zeroable)]
+struct ScreenUniforms {
+    resolution: [f32; 2],
+}
+
+impl ScreenUniforms {
+    fn new(width: u32, height: u32) -> ScreenUniforms {
+        ScreenUniforms {
+            resolution: [width as f32, height as f32],
+        }
+    }
+}
+
 struct State {
     surface: wgpu::Surface,
     device: wgpu::Device,
@@ -52,6 +67,10 @@ struct State {
 
     diffuse_bind_group: wgpu::BindGroup,
 
+    screen_uniform: ScreenUniforms,
+    screen_uniform_buffer: wgpu::Buffer,
+    screen_uniform_bind_group: wgpu::BindGroup,
+
     // Garbage
     mouse_x: f64,
     mouse_y: f64,
@@ -171,6 +190,37 @@ impl State {
             label: Some("diffuse_bind_group"),
         });
 
+        let screen_uniform = ScreenUniforms::new(size.width, size.height);
+        let screen_uniform_buffer = device.create_buffer_init(&wgpu::util::BufferInitDescriptor {
+            label: Some("Screen Uniform Buffer"),
+            contents: bytemuck::cast_slice(&[screen_uniform]),
+            usage: wgpu::BufferUsages::UNIFORM | wgpu::BufferUsages::COPY_DST,
+        });
+
+        let screen_uniform_bind_group_layout =
+            device.create_bind_group_layout(&wgpu::BindGroupLayoutDescriptor {
+                entries: &[wgpu::BindGroupLayoutEntry {
+                    binding: 0,
+                    visibility: wgpu::ShaderStages::VERTEX,
+                    ty: wgpu::BindingType::Buffer {
+                        ty: wgpu::BufferBindingType::Uniform,
+                        has_dynamic_offset: false,
+                        min_binding_size: None,
+                    },
+                    count: None,
+                }],
+                label: Some("screen_bind_group_layout"),
+            });
+
+        let screen_uniform_bind_group = device.create_bind_group(&wgpu::BindGroupDescriptor {
+            layout: &screen_uniform_bind_group_layout,
+            entries: &[wgpu::BindGroupEntry {
+                binding: 0,
+                resource: screen_uniform_buffer.as_entire_binding(),
+            }],
+            label: Some("camera_bind_group"),
+        });
+
         let shader = device.create_shader_module(wgpu::ShaderModuleDescriptor {
             label: Some("Shader"),
             source: wgpu::ShaderSource::Wgsl(include_str!("shader.wgsl").into()),
@@ -179,7 +229,10 @@ impl State {
         let render_pipeline_layout =
             device.create_pipeline_layout(&wgpu::PipelineLayoutDescriptor {
                 label: Some("Render Pipeline Layout"),
-                bind_group_layouts: &[&texture_bind_group_layout],
+                bind_group_layouts: &[
+                    &texture_bind_group_layout,
+                    &screen_uniform_bind_group_layout,
+                ],
                 push_constant_ranges: &[],
             });
 
@@ -242,6 +295,9 @@ impl State {
             vertex_buffer,
             max_vertices,
             diffuse_bind_group,
+            screen_uniform,
+            screen_uniform_buffer,
+            screen_uniform_bind_group,
 
             mouse_x: 0.0,
             mouse_y: 0.0,
@@ -265,7 +321,14 @@ impl State {
         false
     }
 
-    fn update(&mut self) {}
+    fn update(&mut self) {
+        self.screen_uniform = ScreenUniforms::new(self.size.width, self.size.height);
+        self.queue.write_buffer(
+            &self.screen_uniform_buffer,
+            0,
+            bytemuck::cast_slice(&[self.screen_uniform]),
+        );
+    }
 
     fn render(&mut self, commands: Vec<GraphicsCommand>) -> Result<(), wgpu::SurfaceError> {
         let output = self.surface.get_current_texture()?;
@@ -349,19 +412,19 @@ impl State {
                             });
                             vertices.push(Vertex {
                                 position: [sc.x, sc.y + sc.h, 0.0],
-                                tex_coords: [sc.u, sc.v],
+                                tex_coords: [sc.u, sc.v + sc.sh],
                             });
                             vertices.push(Vertex {
                                 position: [sc.x, sc.y + sc.h, 0.0],
-                                tex_coords: [sc.u, sc.v],
+                                tex_coords: [sc.u, sc.v + sc.sh],
                             });
                             vertices.push(Vertex {
                                 position: [sc.x + sc.w, sc.y, 0.0],
-                                tex_coords: [sc.u, sc.v],
+                                tex_coords: [sc.u + sc.sw, sc.v],
                             });
                             vertices.push(Vertex {
                                 position: [sc.x + sc.w, sc.y + sc.h, 0.0],
-                                tex_coords: [sc.u, sc.v],
+                                tex_coords: [sc.u + sc.sw, sc.v + sc.sh],
                             });
                         }
 
@@ -375,6 +438,7 @@ impl State {
                     .write_buffer(&self.vertex_buffer, 0, bytemuck::cast_slice(&vertices));
                 render_pass.set_pipeline(&self.render_pipeline);
                 render_pass.set_bind_group(0, &self.diffuse_bind_group, &[]);
+                render_pass.set_bind_group(1, &self.screen_uniform_bind_group, &[]);
                 render_pass.set_vertex_buffer(0, self.vertex_buffer.slice(..));
                 render_pass.draw(0..(vertices.len() as u32), 0..1);
             }