Cause shader recompilation when changing shader constants in GLES (gfx-rs#8291)

Author: DerSchmale

CHANGELOG.md

@@ -120,6 +120,7 @@ By @cwfitzgerald in [#8999](https://github.com/gfx-rs/wgpu/pull/8999).
 
 - `DisplayHandle` should now be passed to `InstanceDescriptor` for correct EGL initialization on Wayland. By @MarijnS95 in [#8012](https://github.com/gfx-rs/wgpu/pull/8012)
   Note that the existing workaround to create surfaces before the adapter is no longer valid.
+- Changing shader constants now correctly recompiles the shader. By @DerSchmale in [#8291](https://github.com/gfx-rs/wgpu/pull/8291).
 
 ### Documentation
 

wgpu-hal/src/gles/device.rs

@@ -331,6 +331,7 @@ impl super::Device {
                 shader_id: stage.module.id,
                 entry_point: stage.entry_point.to_owned(),
                 zero_initialize_workgroup_memory: stage.zero_initialize_workgroup_memory,
+                constant_hash: Self::create_constant_hash(stage),
             });
         }
         let mut guard = self
@@ -362,6 +363,17 @@ impl super::Device {
         Ok(program)
     }
 
+    fn create_constant_hash(stage: &crate::ProgrammableStage<super::ShaderModule>) -> Vec<u8> {
+        let mut buf: Vec<u8> = Vec::new();
+
+        for (key, value) in stage.constants.iter() {
+            buf.extend_from_slice(key.as_bytes());
+            buf.extend_from_slice(&value.to_ne_bytes());
+        }
+
+        buf
+    }
+
     unsafe fn create_program<'a>(
         gl: &glow::Context,
         shaders: ArrayVec<ShaderStage<'a>, { crate::MAX_CONCURRENT_SHADER_STAGES }>,

wgpu-hal/src/gles/mod.rs

@@ -703,6 +703,7 @@ struct ProgramStage {
     shader_id: ShaderId,
     entry_point: String,
     zero_initialize_workgroup_memory: bool,
+    constant_hash: Vec<u8>,
 }
 
 #[derive(PartialEq, Eq, Hash)]