Examples/Advanced/DeferredShading/DSLights.fp.glsl

   1 #version 120
   2 #extension GL_ARB_texture_rectangle : require
   3 #extension GL_ARB_texture_rectangle : enable
   4
   5 #extension GL_EXT_gpu_shader4 : require
   6 #extension GL_EXT_gpu_shader4 : enable
   7
   8 // forward decls
   9 vec4 OSG_SSME_FP_calcShadow(in vec4 ecFragPos);
  10
  11 uniform sampler2DRect     texBufPos;
  12 uniform sampler2DRect     texBufNorm;
  13 uniform sampler2DRect     texBufDiff;
  14
  15 // compute point light INDEX for fragment at POS with normal NORM
  16 // and diffuse material color MDIFF
  17 vec4 computePointLight(int index, vec3 pos, vec3 norm, vec4 mDiff)
  18 {
  19     vec4  color      = vec4(0., 0., 0., 0.);
  20
  21     vec3  lightDirUN = gl_LightSource[index].position.xyz - pos;
  22     vec3  lightDir   = normalize(lightDirUN);
  23     float NdotL      = max(dot(norm, lightDir), 0.);
  24
  25     if(NdotL > 0.)
  26     {
  27         vec4  shadow    = OSG_SSME_FP_calcShadow(vec4(pos, 1.));
  28
  29         float lightDist = length   (lightDirUN);
  30         float distAtt   = dot(vec3(gl_LightSource[index].constantAttenuation,
  31                                    gl_LightSource[index].linearAttenuation,
  32                                    gl_LightSource[index].quadraticAttenuation),
  33                               vec3(1., lightDist, lightDist * lightDist));
  34         distAtt = 1. / distAtt;
  35
  36         color = shadow * distAtt * NdotL * mDiff * gl_LightSource[index].diffuse;
  37 //        color = shadow * 0.5;
  38     }
  39
  40     return color;
  41 }
  42
  43 // compute directional light INDEX for fragment at POS with normal NORM
  44 // and diffuse material color MDIFF
  45 vec4 computeDirLight(int index, vec3 pos, vec3 norm, vec4 mDiff)
  46 {
  47     vec4 color = vec4(0., 0., 0., 0.);
  48
  49     vec3  lightDir = gl_LightSource[index].position.xyz;
  50     float NdotL    = max(dot(norm, lightDir), 0.);
  51
  52     if(NdotL > 0.)
  53     {
  54         vec4  shadow = OSG_SSME_FP_calcShadow(vec4(pos, 1.));
  55
  56         color = shadow * NdotL * mDiff * gl_LightSource[index].diffuse;
  57     }
  58
  59     return color;
  60 }
  61
  62 // compute spot light INDEX for fragment at POS with normal NORM
  63 // and diffuse material color MDIFF
  64 vec4 computeSpotLight(int index, vec3 pos, vec3 norm, vec4 mDiff)
  65 {
  66     vec4 color = vec4(0., 0., 0., 0.);
  67
  68     vec3  lightDirUN = gl_LightSource[index].position.xyz - pos;
  69     vec3  lightDir   = normalize(lightDirUN);
  70     float spotEffect = dot(-lightDir, gl_LightSource[index].spotDirection);
  71
  72     if(spotEffect > gl_LightSource[index].spotCosCutoff)
  73     {
  74         float NdotL = max(dot(lightDir, norm), 0.);
  75
  76         if(NdotL > 0.)
  77         {
  78             vec4  shadow    = OSG_SSME_FP_calcShadow(vec4(pos, 1.));
  79
  80             float lightDist = length(lightDirUN);
  81             float distAtt   = dot(vec3(gl_LightSource[index].constantAttenuation,
  82                                        gl_LightSource[index].linearAttenuation,
  83                                        gl_LightSource[index].quadraticAttenuation),
  84                                   vec3(1., lightDist, lightDist * lightDist)       );
  85             spotEffect = pow(spotEffect, gl_LightSource[index].spotExponent);
  86             distAtt    = spotEffect / distAtt;
  87
  88             color = shadow * distAtt * NdotL * mDiff * gl_LightSource[index].diffuse;
  89         }
  90     }
  91
  92     return color;
  93 }
  94
  95
  96 void main(void)
  97 {
  98     vec3  norm  = texture2DRect(texBufNorm, gl_FragCoord.xy).xyz;
  99
 100     if(dot(norm, norm) < 0.95)
 101     {
 102         discard;
 103     }
 104     else
 105     {
 106         vec4  posAmb = texture2DRect(texBufPos,  gl_FragCoord.xy);
 107         vec3  pos    = posAmb.xyz;
 108         float amb    = posAmb.w;
 109         vec4  mDiff  = texture2DRect(texBufDiff, gl_FragCoord.xy);
 110
 111         gl_FragColor = computePointLight(0, pos, norm, mDiff);
 112     }
 113 }