fix: align LayerUniformBuffer to 16 bytes for WebGL compat

Author: mazeincoding

apps/web/package.json

@@ -52,7 +52,7 @@
     "nanoid": "^5.1.5",
     "next": "16.1.3",
     "next-themes": "^0.4.4",
-    "opencut-wasm": "^0.2.5",
+    "opencut-wasm": "^0.2.6",
     "pg": "^8.16.2",
     "postgres": "^3.4.5",
     "radix-ui": "^1.4.3",

rust/crates/compositor/src/compositor.rs

@@ -57,6 +57,7 @@ struct LayerUniformBuffer {
     opacity: f32,
     flip_x: f32,
     flip_y: f32,
+    _padding: [f32; 2], // WebGL requires uniform buffer sizes to be multiples of 16 bytes (40 → 48)
 }
 
 #[repr(C)]
@@ -549,6 +550,7 @@ impl Compositor {
                         opacity: layer.opacity,
                         flip_x: if layer.transform.flip_x { 1.0 } else { 0.0 },
                         flip_y: if layer.transform.flip_y { 1.0 } else { 0.0 },
+                        _padding: [0.0; 2],
                     }),
                     usage: wgpu::BufferUsages::UNIFORM | wgpu::BufferUsages::COPY_DST,
                 });