 {
                gl_Position = previousClipPosition;
            }
            
            vec2 screenPosition = (clipPosition.xy / clipPosition.w) * 0.5 + 0.5;
            vec2 previousScreenPosition = (previousClipPosition.xy / previousClipPosition.w) * 0.5 + 0.5;
            vScreenVelocity = screenPosition - previousScreenPosition;
        }
    </script>
    <script type="x-shader/vs" id="vertex-no-velocity">
        #version 300 es

        layout(std140, column_major) uniform;

        layout(loca