vec4 position;

        out vec2 vUV;
        void main() {
            vUV = position.xy * 0.5 + 0.5;
            gl_Position = position;
        }
    </script>
    <script type="x-shader/fs" id="fragment-blur">
        #version 300 es
        precision highp float;

        #define NUM_STEPS 8.0
        #define BLUR_RADIUS 2.0

        uniform sampler2D color;
        uniform sampler2D velocity;

        in vec2 vUV;

        out vec4 fragColor;
        void main() {
            vec2 step = texture(veloc