1 files changed, 23 insertions, 24 deletions

diff --git a/src/preview.rs b/src/preview.rs
index abd9611..f1d4820 100644
--- a/src/preview.rs
+++ b/src/preview.rs
@@ -7,9 +7,7 @@ use eframe::{
     egui_wgpu::{self, wgpu},
 };
 
-pub struct Custom3d {
-    angle: f32,
-}
+pub struct Custom3d;
 
 impl Custom3d {
     pub fn new<'a>(cc: &'a eframe::CreationContext<'a>) -> Option<Self> {
@@ -37,7 +35,7 @@ void main() {
         ));
         resources.insert(format);
 
-        Some(Self { angle: 0.0 })
+        Some(Self)
     }
 }
 
@@ -62,8 +60,8 @@ void main() {
 // The paint callback is called after finish prepare and is given access to egui's main render pass,
 // which can be used to issue draw commands.
 struct CustomTriangleCallback {
-    angle: f32,
     frag_shader: Option<String>,
+    time: f32,
 }
 
 impl egui_wgpu::CallbackTrait for CustomTriangleCallback {
@@ -71,7 +69,7 @@ impl egui_wgpu::CallbackTrait for CustomTriangleCallback {
         &self,
         device: &wgpu::Device,
         queue: &wgpu::Queue,
-        _screen_descriptor: &egui_wgpu::ScreenDescriptor,
+        screen: &egui_wgpu::ScreenDescriptor,
         _egui_encoder: &mut wgpu::CommandEncoder,
         resources: &mut egui_wgpu::CallbackResources,
     ) -> Vec<wgpu::CommandBuffer> {
@@ -84,7 +82,7 @@ impl egui_wgpu::CallbackTrait for CustomTriangleCallback {
             let triangle_resources: &mut TriangleRenderResources = resources.get_mut().unwrap();
             triangle_resources
         }
-        .prepare(device, queue, self.angle);
+        .prepare(device, queue, screen, self.time);
 
         Vec::new()
     }
@@ -102,17 +100,17 @@ impl egui_wgpu::CallbackTrait for CustomTriangleCallback {
 
 impl Custom3d {
     pub fn custom_painting(&mut self, ui: &mut egui::Ui, frag_shader: Option<String>) {
-        let (rect, response) =
-            ui.allocate_exact_size(egui::Vec2::splat(300.0), egui::Sense::drag());
+        let (rect, _) = ui.allocate_exact_size(egui::Vec2::splat(300.0), egui::Sense::drag());
 
-        self.angle += response.drag_motion().x * 0.01;
         ui.painter().add(egui_wgpu::Callback::new_paint_callback(
             rect,
             CustomTriangleCallback {
-                angle: self.angle,
                 frag_shader,
+                time: ui.ctx().input(|i| i.time) as f32,
             },
         ));
+
+        ui.ctx().request_repaint();
     }
 }
 
@@ -132,13 +130,6 @@ impl TriangleRenderResources {
             label: Some("custom3d"),
             source: wgpu::ShaderSource::Glsl {
                 shader: "#version 450
-layout(std140, binding = 0) uniform Uniforms {
-    float angle;
-    float _pad1;
-    float _pad2;
-    float _pad3;
-} uniforms;
-
 out vec2 out_uv;
 
 const vec2 v_positions[3] = vec2[3](
@@ -156,8 +147,6 @@ const vec4 v_colors[3] = vec4[3](
 void main() {
     vec2 pos = v_positions[gl_VertexIndex];
     gl_Position = vec4(pos, 0.0, 1.0);
-
-    gl_Position.x *= cos(uniforms.angle);
     out_uv = gl_Position.xy / 2.0 + 0.5;
 }"
                 .into(),
@@ -178,7 +167,7 @@ void main() {
             label: Some("custom3d"),
             entries: &[wgpu::BindGroupLayoutEntry {
                 binding: 0,
-                visibility: wgpu::ShaderStages::VERTEX,
+                visibility: wgpu::ShaderStages::FRAGMENT,
                 ty: wgpu::BindingType::Buffer {
                     ty: wgpu::BufferBindingType::Uniform,
                     has_dynamic_offset: false,
@@ -240,12 +229,22 @@ void main() {
         }
     }
 
-    fn prepare(&mut self, _device: &wgpu::Device, queue: &wgpu::Queue, angle: f32) {
-        // Update our uniform buffer with the angle from the UI
+    fn prepare(
+        &mut self,
+        _device: &wgpu::Device,
+        queue: &wgpu::Queue,
+        screen: &egui_wgpu::ScreenDescriptor,
+        time: f32,
+    ) {
         queue.write_buffer(
             &self.uniform_buffer,
             0,
-            bytemuck::cast_slice(&[angle, 0.0, 0.0, 0.0]),
+            bytemuck::cast_slice(&[
+                screen.size_in_pixels[0] as f32,
+                screen.size_in_pixels[1] as f32,
+                time,
+                0.0,
+            ]),
         );
     }