This commit fixes crashes (SIGSEGV in CImg blur_bilateral) and black-frame
corruption artifacts during playback and scrubbing on macOS Apple Silicon.
Root cause analysis:
1. macOS uses Tile-Based Deferred Rendering (TBDR). glFlush() does not
guarantee tile memory writeback, causing glReadPixels to read incomplete
tiles (black/corrupted frames) and cache them to disk.
2. Olive uses multiple shared OpenGL contexts (RenderProcessor contexts vs.
thread-local PluginRenderer context). glFinish() only waits for the
current context, not the shared context that produced the texture. CPU
readback in PluginRenderer could read partially-rendered tiles.
3. OlivePluginInstance and OliveClipInstance are not thread-safe. Concurrent
RenderProcessors could corrupt internal QMap/images_ and params_ via
setInputTexture/renderAction races.
Fixes:
- OpenGLRenderer::Flush() on macOS now uses glFinish() unconditionally.
- OpenGLRenderer::DownloadFromTexture() and OpenGLRenderer::Blit() insert
glFinish() before readback/detach to ensure tile writeback completes.
- PluginRenderer::RenderPlugin() now acquires a per-instance mutex to
serialize concurrent OFX render calls.
- Before CPU readback in PluginRenderer, flush the renderer that originally
produced each input texture, ensuring cross-context synchronization.
- RenderProcessor::ProcessVideoFootage() flushes after BlitColorManaged.
- Add black-frame detection in ProcessVideoCacheJob() to auto-purge TBDR-
corrupted cache files.
- Add diagnostic qDebug() logging in viewer, decoder, renderer, and plugin
paths to aid future debugging.
Mike-Solar
2a84027ff9