playcanvas
Version:
Open-source WebGL/WebGPU 3D engine for the web
37 lines (36 loc) • 1.03 kB
JavaScript
class WebglDrawCommands {
indexSizeBytes;
glCounts = null;
glOffsetsBytes = null;
glInstanceCounts = null;
constructor(indexSizeBytes) {
this.indexSizeBytes = indexSizeBytes;
}
allocate(maxCount) {
if (this.glCounts && this.glCounts.length === maxCount) {
return;
}
this.glCounts = new Int32Array(maxCount);
this.glOffsetsBytes = new Int32Array(maxCount);
this.glInstanceCounts = new Int32Array(maxCount);
}
add(i, indexOrVertexCount, instanceCount, firstIndexOrVertex) {
this.glCounts[i] = indexOrVertexCount;
this.glOffsetsBytes[i] = firstIndexOrVertex * this.indexSizeBytes;
this.glInstanceCounts[i] = instanceCount;
}
update(count) {
let totalPrimitives = 0;
if (this.glCounts && this.glInstanceCounts && count > 0) {
for (let d = 0; d < count; d++) {
const indexOrVertexCount = this.glCounts[d];
const instanceCount = this.glInstanceCounts[d];
totalPrimitives += indexOrVertexCount * instanceCount;
}
}
return totalPrimitives;
}
}
export {
WebglDrawCommands
};