playcanvas/build/playcanvas.dbg/src/scene/shader-lib/chunks/gsplat/vert/gsplatSource.js

PlayCanvas WebGL game engine

var gsplatSourceVS = "\nattribute vec3 vertex_position;         // xy: cornerUV, z: render order offset\nattribute uint vertex_id_attrib;        // render order base\n\nuniform uint numSplats;                 // total number of splats\nuniform highp usampler2D splatOrder;    // per-splat index to source gaussian\n\n// initialize the splat source structure\nbool initSource(out SplatSource source) {\n    uint w = uint(textureSize(splatOrder, 0).x);\n\n    // calculate splat order\n    source.order = vertex_id_attrib + uint(vertex_position.z);\n\n    // return if out of range (since the last block of splats may be partially full)\n    if (source.order >= numSplats) {\n        return false;\n    }\n\n    ivec2 orderUV = ivec2(source.order % w, source.order / w);\n\n    // read splat id\n    source.id = texelFetch(splatOrder, orderUV, 0).r;\n\n    // map id to uv\n    source.uv = ivec2(source.id % w, source.id / w);\n\n    // get the corner\n    source.cornerUV = vertex_position.xy;\n\n    return true;\n}\n";

export { gsplatSourceVS as default };