uniform int iUseTexture0;
uniform int iUseTexture1;
uniform int iUseTexture2;
uniform int iUseTexture3;

uniform sampler2D iTexture0;
uniform sampler2D iTexture1;
uniform sampler2D iTexture2;
uniform sampler2D iTexture3;

uniform vec4 iClipPlane;
uniform int iUseClipPlane;
uniform int iUseLighting;
uniform int iMultiplyAmbient;

//fog-related uniforms
uniform int iFogEnabled;
uniform int iFogMode; //0 - linear, 1 - exp, 2 - exp2
uniform float iFogDensity;
uniform float iFogStart;
uniform float iFogEnd;
uniform vec3 iFogCol;

varying vec3 iPositionWorld;
varying vec3 iPositionCamera;
varying vec3 iNormalCamera;

uniform float resolution;
uniform float radius;
uniform vec2 dir;

uniform float screenWidth = 1920;
uniform float screenHeight = 1080;





void main()
{

  //clipping plane part of shader
  if (iUseClipPlane == 1 && dot(iPositionWorld, iClipPlane.xyz) < iClipPlane.w) {
    discard;
  }

  vec3 N = normalize(iNormalCamera);
  vec3 v = normalize(iPositionCamera);
  vec3 R = reflect(-v,N);

  vec4 ambient = vec4(0,0,0,0);
  vec4 diffuse = vec4(0,0,0,0);
  vec4 specular = vec4(0,0,0,0);

  //ambient component
  if (iUseTexture1 == 1) {
    ambient = texture2D(iTexture1, gl_TexCoord[1].xy);
  }
  ambient.w = 1.0;

  //diffuse component
  if (iUseTexture0 == 1) {
    diffuse = texture2D(iTexture0, gl_TexCoord[0].xy);
  }
  else {
    diffuse = gl_FrontMaterial.diffuse;
  }

  if(ambient.w < 0.01 || diffuse.w < 0.01) {
    discard;
  }
  if (iUseLighting == 1) {
    diffuse.xyz *= abs(dot(N, v));
  }

  //specular component - note disabled if "lighting" is off
  if (iUseLighting == 1) {

    //specular component
    if (iUseTexture2 == 1) {
      specular = texture2D(iTexture2, gl_TexCoord[2].xy);
    }
    else {
      specular = gl_FrontMaterial.specular;
    }

    //specular *= clamp(pow(max(dot(R,v),0.0), gl_FrontMaterial.shininess), 0.0, 1.0);
    //specular *= pow(max(dot(R,v),0.0), max(gl_FrontMaterial.shininess, 1.0));
    specular *= pow(max(dot(R,v),0.0), max(gl_FrontMaterial.shininess, 1.0));
    if (iUseTexture3 == 1) {
      specular *= texture2D(iTexture3, gl_TexCoord[3].xy);
    }

  }
  specular.w = 1.0;

  //global scaling via colour
  gl_FragColor = gl_Color;
  if (iMultiplyAmbient == 0) {
    gl_FragColor.xyz *= (ambient + diffuse + specular).xyz;
  }
  else {
    if (iUseTexture1 == 1) {
        //gl_FragColor.xyz *= ((vec4(1,1,1,1) * 0.2 + ambient * 0.8) * diffuse + specular).xyz;
        gl_FragColor.xyz *= (0.1 + ambient * diffuse * 1.25).xyz;
    }
    else {
        gl_FragColor.xyz *= (diffuse + specular).xyz;
        //gl_FragColor.xyz *= (diffuse).xyz;
    }

  }

  if (iUseTexture0 == 1) {
    gl_FragColor.w = diffuse.w;
  }

  //apply fog
  if (iFogEnabled == 1) {

    //compute length from eye to fragment
    float c = length(iPositionCamera);

    //compute blend value
    float f;
    if (iFogMode == 0) {
      f = (iFogEnd - c) / (iFogEnd - iFogStart);
    }
    else if (iFogMode == 1) {
      f = exp(-iFogDensity * c);
    }
    else if (iFogMode == 2) {
      f = exp(-(iFogDensity * c)*(iFogDensity * c));
    }
    f = clamp(f, 0, 1);

    //blend with fragment's post-texturing colour using the appropriate blending factor
    gl_FragColor.xyz = gl_FragColor.xyz * f + iFogCol * (1.0 - f);

  }

  // Converting (x,y,z) to range [0,1]
float x = gl_FragCoord.x/screenWidth;
float y = gl_FragCoord.y/screenHeight;
float z = gl_FragCoord.z; // Already in range [0,1]

// Converting from range [0,1] to NDC [-1,1]
float ndcx = x * 2.0 - 1.0;
float ndcy = y * 2.0 - 1.0;
float ndcz = z * 2.0 - 1.0;
vec3 ndc = vec3(ndcx, ndcy, ndcz);

	vec4 blurSample = 0.0;
	vec4 tmpPix;
	vec4 offPix;
	vec2 uv = vec2(ndcx, ndcy);
	for(int i=-4;i<5;i++)
	{
		tmpPix = texture2D(iTexture0,uv + vec2( i*0.005,0 ));
		offPix = -0.3+tmpPix;
		offPix = offPix * 15;
		if( (offPix.r+offPix.g+offPix.b)>0 )
		{
                blurSample = blurSample + offPix;
		}
	}

	for(int i=-4;i<5;i++)
	{
		tmpPix = texture2D(iTexture0,uv + vec2( 0,i*0.005 ));
              	offPix = -0.3+tmpPix;
		offPix = offPix * 15;
		if( (offPix.r+offPix.g+offPix.b)>0 )
		{
			blurSample += offPix;
		}

	}

	blurSample = blurSample / 64;
	gl_FragColor.xyz = blurSample*1.2;


}