playcanvas/build/playcanvas/src/platform/graphics/webgl/webgl-buffer.js

PlayCanvas WebGL game engine

import { BUFFER_GPUDYNAMIC, BUFFER_STREAM, BUFFER_DYNAMIC, BUFFER_STATIC } from '../constants.js';

class WebglBuffer {
		destroy(device) {
				if (this.bufferId) {
						device.gl.deleteBuffer(this.bufferId);
						this.bufferId = null;
				}
		}
		get initialized() {
				return !!this.bufferId;
		}
		loseContext() {
				this.bufferId = null;
		}
		unlock(device, usage, target, storage) {
				const gl = device.gl;
				if (!this.bufferId) {
						let glUsage;
						switch(usage){
								case BUFFER_STATIC:
										glUsage = gl.STATIC_DRAW;
										break;
								case BUFFER_DYNAMIC:
										glUsage = gl.DYNAMIC_DRAW;
										break;
								case BUFFER_STREAM:
										glUsage = gl.STREAM_DRAW;
										break;
								case BUFFER_GPUDYNAMIC:
										glUsage = gl.DYNAMIC_COPY;
										break;
						}
						this.bufferId = gl.createBuffer();
						gl.bindBuffer(target, this.bufferId);
						gl.bufferData(target, storage, glUsage);
				} else {
						gl.bindBuffer(target, this.bufferId);
						gl.bufferSubData(target, 0, storage);
				}
		}
		constructor(){
				this.bufferId = null;
		}
}

export { WebglBuffer };