uniform highp mat4 matrix; uniform highp vec2 textureScale; uniform highp vec2 shift; uniform highp float dpr; attribute highp vec4 vCoord; attribute highp vec2 tCoord; varying highp vec2 sampleCoord; varying highp vec2 shiftedSampleCoord; void main() { sampleCoord = tCoord * textureScale; shiftedSampleCoord = (tCoord - shift) * textureScale; gl_Position = matrix * floor(vCoord * dpr + 0.5) / dpr; }