_updateDimension({width, height, video}) {
const {videoTexture, model, transformFeedback, gl} = this;
if (width === videoTexture.width && height === videoTexture.height) {
return;
}
// video.width = width;
// video.height = height;
videoTexture.resize({width: video.videoWidth, height: video.videoHeight});
const vertexCount = width * height;
model.setVertexCount(vertexCount);
// update attribute
const uv = new Float32Array(2 * vertexCount);
let i = 0;
for (let y = 0; y < height; y++) {
for (let x = 0; x < width; x++) {
uv[i++] = (x + 0.5) / width;
uv[i++] = (y + 0.5) / height;
}
}
model.setAttributes({uv: {size: 2, value: uv}});
const iconFrameBuffer = new Buffer(gl, {
size: 4,
instanced: 1,
data: new Float32Array(4 * vertexCount),
usage: GL.DYNAMIC_COPY
});
const colorBuffer = new Buffer(gl, {
size: 4,
instanced: 1,
data: new Float32Array(4 * vertexCount),
usage: GL.DYNAMIC_COPY
});
this.buffers = {
instanceIconFrames: iconFrameBuffer,
instanceColors: colorBuffer
};
transformFeedback.setBuffers({
0: iconFrameBuffer,
1: colorBuffer
});
}
getBuffers({width, height, video}) {
const {model, videoTexture, transformFeedback} = this;
this._updateDimension({width, height, video});
videoTexture.setSubImageData({width: video.videoWidth, height: video.videoHeight, data: video});
model.draw({
uniforms: {
video: videoTexture
},
transformFeedback,
parameters: {
[GL.RASTERIZER_DISCARD]: true
}
});
return this.buffers;
}