{"record":{"id":"61b5e024ee12e427","repo":"MiniMax-AI/skills","slug":"no-webgl2","errorCode":null,"errorMessage":"No WebGL2","messagePattern":"No WebGL2","errorType":"exception","errorClass":"Error","httpStatus":null,"severity":"error","filePath":"skills/shader-dev/techniques/simulation-physics.md","lineNumber":21,"sourceCode":"### WebGL2 Multi-Pass Rendering Complete Template\n\nBelow is a complete standalone HTML template demonstrating how to set up WebGL2 double buffering (ping-pong) for physics simulation:\n\n**IMPORTANT: WebGL2 ping-pong core rule: The texture bound to the write-target framebuffer must never simultaneously serve as input for any iChannel.** Violating this rule causes undefined behavior (typically all-black/all-zero output).\n\nFor simulations requiring \"current frame\" and \"previous frame\" two time steps (such as the wave equation), use **dual-channel encoding**: R channel stores current height, G channel stores previous frame height. This way only one buffer is read from (iChannel0 = currentBuf), writing to another buffer (nextBuf), avoiding read-write conflicts.\n\n```html\n\n\nGPU Physics\n\n\n\n