From e50db1721f67a6c1b565b0ac151ba32fcae21cbf Mon Sep 17 00:00:00 2001 From: skal Date: Mon, 9 Feb 2026 10:34:01 +0100 Subject: fix: Resolve WebGPU uniform buffer alignment issues (Task #74) Fixed multiple WGSL/C++ struct alignment mismatches causing validation errors: Padding fixes: - fade_effect.cc: Changed EffectParams padding from vec3 to _pad0/1/2 - theme_modulation_effect.cc: Same padding fix for EffectParams - Root cause: WGSL vec3 has 16-byte alignment, creating 32-byte structs ODR violation fix: - demo_effects.h: Added includes for fade_effect.h, theme_modulation_effect.h - Removed incomplete forward declarations (88 bytes) conflicting with complete definitions (96 bytes), causing heap buffer overflow in make_shared Member shadowing cleanup: - Renamed Effect::uniforms_ shadowing members to descriptive names: - FadeEffect: uniforms_ -> common_uniforms_ - FlashEffect: uniforms_ -> flash_uniforms_ - ThemeModulationEffect: uniforms_ -> common_uniforms_ Results: - demo64k runs without crashes - 33/33 tests passing (100%) - Added Task #75: WGSL uniform validation tool handoff(Claude): Uniform buffer alignment debugged and fixed --- src/gpu/effects/theme_modulation_effect.cc | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) (limited to 'src/gpu/effects/theme_modulation_effect.cc') diff --git a/src/gpu/effects/theme_modulation_effect.cc b/src/gpu/effects/theme_modulation_effect.cc index fc52b62..f9ae636 100644 --- a/src/gpu/effects/theme_modulation_effect.cc +++ b/src/gpu/effects/theme_modulation_effect.cc @@ -26,7 +26,9 @@ ThemeModulationEffect::ThemeModulationEffect(const GpuContext& ctx) struct EffectParams { theme_brightness: f32, - _pad: vec3, + _pad0: f32, + _pad1: f32, + _pad2: f32, }; @group(0) @binding(0) var inputSampler: sampler; @@ -59,14 +61,14 @@ ThemeModulationEffect::ThemeModulationEffect(const GpuContext& ctx) pipeline_ = create_post_process_pipeline(ctx_.device, ctx_.format, shader_code); - uniforms_.init(ctx_.device); + common_uniforms_.init(ctx_.device); params_buffer_ = gpu_create_buffer( ctx_.device, 16, WGPUBufferUsage_Uniform | WGPUBufferUsage_CopyDst); } void ThemeModulationEffect::update_bind_group(WGPUTextureView input_view) { pp_update_bind_group(ctx_.device, pipeline_, &bind_group_, input_view, - uniforms_.get(), params_buffer_); + common_uniforms_.get(), params_buffer_); } void ThemeModulationEffect::render(WGPURenderPassEncoder pass, float time, @@ -79,7 +81,7 @@ void ThemeModulationEffect::render(WGPURenderPassEncoder pass, float time, .beat = beat, .audio_intensity = intensity, }; - uniforms_.update(ctx_.queue, u); + common_uniforms_.update(ctx_.queue, u); // Alternate between bright and dark every 4 seconds (2 pattern changes) // Music patterns change every 2 seconds at 120 BPM -- cgit v1.2.3