1 files changed, 37 insertions, 0 deletions
diff --git a/src/gpu/post_process_helper.h b/src/gpu/post_process_helper.h
new file mode 100644
index 0000000..1c649e7
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+++ b/src/gpu/post_process_helper.h
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+// This file is part of the 64k demo project.
+// It declares helper functions for post-processing effects.
+
+#pragma once
+
+#include "gpu/gpu.h"
+#include "util/mini_math.h"
+
+// Uniform data common to all post-processing effects
+struct CommonPostProcessUniforms {
+  vec2 resolution;      // Screen dimensions
+  float aspect_ratio;   // Width/height ratio
+  float time;           // Physical time in seconds (unaffected by tempo)
+  float beat_time;      // Musical time in beats (absolute, tempo-scaled)
+  float beat_phase;     // Fractional beat (0.0-1.0 within current beat)
+  float audio_intensity;// Audio peak for beat sync
+  float _pad;           // Padding for 16-byte alignment
+};
+static_assert(sizeof(CommonPostProcessUniforms) == 32,
+              "CommonPostProcessUniforms must be 32 bytes for WGSL alignment");
+
+// Standard post-process bind group layout (group 0):
+#define PP_BINDING_SAMPLER 0       // Sampler for input texture
+#define PP_BINDING_TEXTURE 1       // Input texture (previous render pass)
+#define PP_BINDING_UNIFORMS 2      // Custom uniforms buffer
+#define PP_BINDING_EFFECT_PARAMS 3 // Effect-specific parameters
+
+// Helper to create a standard post-processing pipeline
+// Uniforms are accessible to both vertex and fragment shaders
+WGPURenderPipeline create_post_process_pipeline(WGPUDevice device,
+                                                WGPUTextureFormat format,
+                                                const char* shader_code);
+
+// Helper to update bind group for post-processing effects
+void pp_update_bind_group(WGPUDevice device, WGPURenderPipeline pipeline,
+                          WGPUBindGroup* bind_group, WGPUTextureView input_view,
+                          GpuBuffer uniforms, GpuBuffer effect_params);