adBuffer(gl.COLOR_ATTACHMENT0);
        gl.readPixels(0, 0, dstSize, dstSize, gl.RGBA, gl.UNSIGNED_BYTE, srgbPixels0);
        gl.readBuffer(gl.COLOR_ATTACHMENT2);
        gl.readPixels(0, 0, dstSize, dstSize, gl.RGBA, gl.UNSIGNED_BYTE, srgbPixels1);
    }

    if (drawbuffersFormatMask & linearMask) {
        gl.readBuffer(gl.COLOR_ATTACHMENT1);
        gl.readPixels(0, 0, dstSize, dstSize, gl.RGBA, gl.UNSIGNED_BYTE, linearPixels0);
        gl.readBuffer(gl.COLOR_ATTACHMENT3);
        gl.readPixels(0, 0, d