eframe support for wgpu on the web

crates/egui-wgpu/src/renderer.rs

@@ -1,5 +1,6 @@
 #![allow(unsafe_code)]
 
+use std::num::NonZeroU64;
 use std::{borrow::Cow, collections::HashMap, num::NonZeroU32};
 
 use egui::{epaint::Primitive, PaintCallbackInfo};
@@ -26,7 +27,7 @@ use wgpu::util::DeviceExt as _;
 ///
 /// # Example
 ///
-/// See the [`custom3d_glow`](https://github.com/emilk/egui/blob/master/crates/egui_demo_app/src/apps/custom3d_wgpu.rs) demo source for a detailed usage example.
+/// See the [`custom3d_wgpu`](https://github.com/emilk/egui/blob/master/crates/egui_demo_app/src/apps/custom3d_wgpu.rs) demo source for a detailed usage example.
 pub struct CallbackFn {
     prepare: Box<PrepareCallback>,
     paint: Box<PaintCallback>,
@@ -175,7 +176,7 @@ impl Renderer {
                     visibility: wgpu::ShaderStages::VERTEX,
                     ty: wgpu::BindingType::Buffer {
                         has_dynamic_offset: false,
-                        min_binding_size: None,
+                        min_binding_size: NonZeroU64::new(std::mem::size_of::<UniformBuffer>() as _),
                         ty: wgpu::BufferBindingType::Uniform,
                     },
                     count: None,

crates/egui_demo_app/src/apps/custom3d_wgpu.rs

@@ -1,4 +1,4 @@
-use std::sync::Arc;
+use std::{num::NonZeroU64, sync::Arc};
 
 use eframe::{
     egui_wgpu::{self, wgpu},
@@ -30,7 +30,7 @@ impl Custom3d {
                 ty: wgpu::BindingType::Buffer {
                     ty: wgpu::BufferBindingType::Uniform,
                     has_dynamic_offset: false,
-                    min_binding_size: None,
+                    min_binding_size: NonZeroU64::new(16),
                 },
                 count: None,
             }],
@@ -165,7 +165,11 @@ struct TriangleRenderResources {
 impl TriangleRenderResources {
     fn prepare(&self, _device: &wgpu::Device, queue: &wgpu::Queue, angle: f32) {
         // Update our uniform buffer with the angle from the UI
-        queue.write_buffer(&self.uniform_buffer, 0, bytemuck::cast_slice(&[angle]));
+        queue.write_buffer(
+            &self.uniform_buffer,
+            0,
+            bytemuck::cast_slice(&[angle, 0.0, 0.0, 0.0]),
+        );
     }
 
     fn paint<'rp>(&'rp self, render_pass: &mut wgpu::RenderPass<'rp>) {

crates/egui_demo_app/src/apps/custom3d_wgpu_shader.wgsl

@@ -8,6 +8,10 @@ struct Uniforms {
     _padding: vec3<f32>, // needed in order to make it 16 byte aligned
 };
 
+struct Uniforms {
+    @size(16) angle: f32, // pad to 16 bytes
+};
+
 @group(0) @binding(0)
 var<uniform> uniforms: Uniforms;