varying vec2 v_texCoord;
uniform vec2 rubyTextureSize;
uniform vec2 rubyInputSize;
uniform vec2 rubyOutputSize;

#if defined(VERTEX)
attribute vec4 a_position;

void main() {
  vec2 ratio = max(floor((rubyOutputSize+0.0001)/rubyInputSize), 1.0);
  vec4 clean = vec4(ratio*rubyInputSize/rubyOutputSize, 1.0, 1.0);

  gl_Position = a_position * clean;
  v_texCoord = vec2(a_position.x+1.0,1.0-a_position.y)/2.0*rubyInputSize;
}

#elif defined(FRAGMENT)
uniform sampler2D rubyTexture;

void main() {
  gl_FragColor = texelFetch(rubyTexture, ivec2(v_texCoord), 0);
}
#endif