#version 110 uniform bool horiz; uniform bool vert; uniform sampler2D myTexture; varying vec2 vTexCoord; void main(void) { float x = vTexCoord.x; float y = vTexCoord.y; if (horiz) x = 1.0 - x; if (vert) y = 1.0 - y; vec4 textureColor = texture2D(myTexture, vec2(x, y)); gl_FragColor = vec4( textureColor.r, textureColor.g, textureColor.b, textureColor.a ); }