uniform highp sampler2D original; uniform lowp float qt_Opacity; uniform lowp vec4 color; uniform highp float horizontalOffset; uniform highp float verticalOffset; varying highp vec2 qt_TexCoord0; void main(void) { highp vec2 pos = qt_TexCoord0 - vec2(horizontalOffset, verticalOffset); lowp float ea = step(0.0, pos.x) * step(0.0, pos.y) * step(pos.x, 1.0) * step(pos.y, 1.0); lowp float eb = 1.0 - ea; gl_FragColor = eb * color + ea * color * (1.0 - texture2D(original, pos).a) * qt_Opacity; }