From 6ef8f578817ee0134fd5867ca3b80590e3eb2368 Mon Sep 17 00:00:00 2001 From: skal Date: Thu, 14 May 2026 19:09:39 +0200 Subject: ans: order-0 rANS coder + WGSL asset compression Adds src/util/ans.{h,cc}, a per-chunk-adaptive order-0 rANS entropy coder. Decoder is always built; encoder is gated on ANS_ENABLE_ENCODER (tools only). Both sides take an optional 256-entry initial_counts table to seed the adaptive model. The per-chunk initial state is (1 << kBits). Higher initial states (e.g. with a signature packed into the upper bits) force a renorm-emit at iter 0 that the decoder never consumes, corrupting multi-chunk streams once stats become skewed. Asset pipeline: - AssetRecord gains 'compression' and 'uncompressed_size' fields. - asset_packer scans every WGSL file to build a corpus-wide byte histogram, then ANS-encodes each shader using that histogram as the seed. Histogram and accessor are emitted alongside the asset table. Round-trip verification runs at pack time for every compressed asset; failures fall back to uncompressed storage. - asset_manager decompresses on first GetAsset(), caches the heap-allocated buffer, and DropAsset / ReloadAssetsFromFile free it along with the procedural cache. - Disk-load (dev) builds are unchanged: WGSL paths stay as filenames. Tests: - src/tests/util/test_ans.cc: roundtrip variants (empty, single byte, single-symbol run, all-zeros, random uniform/skewed, repeated ASCII), seeded-vs-uniform compression, rejection of mismatched counts / corruption / truncation, PeekUncompressedSize. - 37/37 dev, 36/36 STRIP_ALL. Compression observed: WGSL shaders shrink to ~0.62-0.71x in the main workspace (81 of 105 assets qualify). Docs: - doc/ANS.md (new): algorithm, bitstream, API, asset pipeline integration, compression numbers, limitations, tests. - doc/ASSET_SYSTEM.md: new Compression section + updated technical guarantees for compressed assets. - doc/COMPLETED.md: May 2026 entry. - PROJECT_CONTEXT.md: Build status line mentions WGSL ANS compression. - CLAUDE.md, GEMINI.md: tier-3 build doc list includes ANS.md. --- cmake/DemoTests.cmake | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'cmake/DemoTests.cmake') diff --git a/cmake/DemoTests.cmake b/cmake/DemoTests.cmake index 59859c5..c6d8b7d 100644 --- a/cmake/DemoTests.cmake +++ b/cmake/DemoTests.cmake @@ -10,6 +10,10 @@ add_demo_test(test_maths MathUtilsTest util src/tests/util/test_maths.cc) add_demo_test(test_file_watcher FileWatcherTest util src/tests/util/test_file_watcher.cc) target_link_libraries(test_file_watcher PRIVATE util ${DEMO_LIBS}) +add_demo_test(test_ans AnsCoderTest util src/tests/util/test_ans.cc src/util/ans.cc) +target_compile_definitions(test_ans PRIVATE ANS_ENABLE_ENCODER) +target_link_libraries(test_ans PRIVATE ${DEMO_LIBS}) + add_demo_test(test_synth SynthEngineTest audio src/tests/audio/test_synth.cc ${GEN_DEMO_CC}) target_link_libraries(test_synth PRIVATE audio util procedural ${DEMO_LIBS}) demo_add_asset_deps(test_synth audio) -- cgit v1.2.3