#ifdef GL_ES
precision mediump int;
precision mediump float;
#endif

#define USE_OGRE_FROM_FUTURE
#include <OgreUnifiedShader.h>

SAMPLER2D(RT, 0);

OGRE_UNIFORMS(
uniform float scale;
uniform float pixelSize;
)

MAIN_PARAMETERS
IN(vec2 oUv0, TEXCOORD0)
MAIN_DECLARATION
{
  vec2 samples[4];
	samples[0] = vec2(0, -1);
	samples[1] = vec2(-1, 0);
	samples[2] = vec2(1, 0);
	samples[3] = vec2(0, 1);

  vec4 tc = texture2D(RT, oUv0);
  vec4 laplace = vec4_splat(-4.0) * tc;

  // Sample the neighbor pixels
  for (int i = 0; i < 4; i++){
     laplace += texture2D(RT, oUv0 + vec2_splat(pixelSize) * samples[i]);
  }

  gl_FragColor = vec4_splat(1.0) - (vec4_splat(0.5 + scale) * laplace);
}