# 64k Demo Project Goal: - Produce a <=64k native demo binary - Same C++ codebase for Windows, macOS, Linux Graphics: - WebGPU via wgpu-native - WGSL shaders - Single fullscreen pass initially Audio: - 32 kHz, 16-bit mono - Procedurally generated samples - No decoding, no assets Constraints: - Size-sensitive - Minimal dependencies - Explicit control over all allocations Style: - Demoscene - No engine abstractions Incoming tasks in no particular order: - 1. add a fullscreen mode (as command line option) - 2. parse the keyboard key. Exit the demo when 'esc' is pressed. Toggle full-screen when 'f' is pressed. - 3. add binary crunchers for all platforms - 4. add cross-compilation for PC+linux (x86_64) and PC+Windows (.exe binary) - 5. implement a spectrogram editor for representing .spec with elementary shapes (bezier curves, lines, random noise, rectangles...) as a mean of compression - 6. add a scripting tool to edit the demo (compiled into the binary at the end) - 7. compile wgpu-native in optimized mode (not unoptimized) - 8. add a #define STRIP_ALL to remove all unnecessary code for the final build (for instance, command-line args parsing, or unnecessary options, constant parameters to function calls, etc.) ## Session Decisions and Current State ### Audio Engine (Synth): - **Architecture**: Real-time additive synthesis from spectrograms using Inverse Discrete Cosine Transform (IDCT). - **Dynamic Updates**: Implemented a double-buffering (flip-flop) mechanism for thread-safe, real-time updates of spectrogram data. The main thread writes to a back buffer, which is then atomically swapped to become the active front buffer for the audio thread, avoiding real-time allocations and locks. - **Sample Generation**: Samples are generated in the frequency domain (spectrograms) and converted to time-domain audio using IDCT with a Hamming window. - **Audio Input Support (`spectool`)**: Supports WAV and MP3 input for analysis (leveraging `miniaudio`'s built-in decoders). AAC is explicitly *not* supported due to complexity and dependency constraints. ### Tools Developed: - `spectool`: A command-line tool for analyzing WAV/MP3 files into `.spec` spectrogram format and for playing back `.spec` files through the synth engine. - `specview`: A command-line tool for visualizing `.spec` spectrogram files in ASCII art. ### Coding Style: - **Standard**: Adopted a consistent coding style enforced by `.clang-format`. - **Rules**: 2-space indentation, no tabs, 80-column line limit. - **File Extension**: All C++ source files renamed from `.cpp` to `.cc`. ### Development Workflow: - **Commit Policy**: Explicit rule to always run the full test suite before preparing any commit, documented in `CONTRIBUTING.md`.