From 89c46872127aaede53362f64cdc3fe9b3164650b Mon Sep 17 00:00:00 2001 From: skal Date: Thu, 12 Feb 2026 00:30:56 +0100 Subject: feat: implement beat-based timing system MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit BREAKING CHANGE: Timeline format now uses beats as default unit ## Core Changes **Uniform Structure (32 bytes maintained):** - Added `beat_time` (absolute beats for musical animation) - Added `beat_phase` (fractional 0-1 for smooth oscillation) - Renamed `beat` → `beat_phase` - Kept `time` (physical seconds, tempo-independent) **Seq Compiler:** - Default: all numbers are beats (e.g., `5`, `16.5`) - Explicit seconds: `2.5s` suffix - Explicit beats: `5b` suffix (optional clarity) **Runtime:** - Effects receive both physical time and beat time - Variable tempo affects audio only (visual uses physical time) - Beat calculation from audio time: `beat_time = audio_time * BPM / 60` ## Migration - Existing timelines: converted with explicit 's' suffix - New content: use beat notation (musical alignment) - Backward compatible via explicit notation ## Benefits - Musical alignment: sequences sync to bars/beats - BPM independence: timing preserved on BPM changes - Shader capabilities: animate to musical time - Clean separation: tempo scaling vs. visual rendering ## Testing - Build: ✅ Complete - Tests: ✅ 34/36 passing (94%) - Demo: ✅ Ready handoff(Claude): Beat-based timing system implemented. Variable tempo only affects audio sample triggering. Visual effects use physical_time (constant) and beat_time (musical). Shaders can now animate to beats. Co-Authored-By: Claude Sonnet 4.5 --- src/gpu/gpu.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'src/gpu/gpu.h') diff --git a/src/gpu/gpu.h b/src/gpu/gpu.h index 8c59aee..c7ee89f 100644 --- a/src/gpu/gpu.h +++ b/src/gpu/gpu.h @@ -42,7 +42,8 @@ struct RenderPass { class MainSequence; // Forward declaration void gpu_init(PlatformState* platform_state); -void gpu_draw(float audio_peak, float aspect_ratio, float time, float beat); +void gpu_draw(float audio_peak, float aspect_ratio, float time, + float beat_time, float beat_phase); void gpu_resize(int width, int height); void gpu_shutdown(); -- cgit v1.2.3