//
// Standard
//

#include "atmosphere.cg"
#include "lighting.cg"
#include "shadowmapping.cg"

// Vertex to pixel shader structure
struct v2p
{
  float2 tc0            : TEXCOORD0;
  float3 Direction      : TEXCOORD1;
  float4 RayleighColor  : TEXCOORD2;
  float4 MieColor       : TEXCOORD3;
  float4 Position       : TEXCOORD4;    // For fragment shader
  float3 normal         : TEXCOORD5;
  float  extinction     : TEXCOORD6;
  float3 R              : TEXCOORD7;    // Reflection vector
};

void main(
  // In
  in v2p IN,

  // Out
  out float4 outColor : COLOR0,
#ifdef CSM_MRT
  out float4 outShadow : COLOR1,
#endif
  
  // Constants
  uniform sampler2D   baseMap : TEXUNIT0,
  uniform samplerCUBE envMap  : TEXUNIT1,
  uniform float3    lightDirection,
  uniform float3    lightColor,
  uniform float3    lightAmbient,
  uniform float3    eyePosW,
  uniform float     atmosRayleigh,
  uniform float     atmosMie,
  uniform float3    Ke,
  uniform float3    Ka,
  uniform float3    Kd,
  uniform float3    Ks,
  uniform float     Kr,
  uniform float     shininess,
#ifdef CSM
  // shadow mapping
	uniform sampler2D    shadowArray  : TEXUNIT7,
  uniform float4x4     smTexMatArray[SM_MAX_SPLITS],  
  uniform float smSplits, 
#endif
  uniform float     sunny,
  uniform float     exposure
)
{
  float3 skyColor;
  
#ifdef CSM
  // Output shadowing
  float shadow = GetShadowFactor(IN.Position, IN.normal,shadowArray, smTexMatArray, smSplits, lightDirection)*sunny;
  //outShadow.rgb = IN.normal;   
#else
  const float shadow=1;
#endif

  // Get sky gradient color
  skyColor.rgb=GetSkyColor(lightDirection,IN.Direction,IN.RayleighColor,IN.MieColor,atmosRayleigh,atmosMie,lightColor,lightAmbient);

  // Get base texture color
  float4 baseCol=tex2D(baseMap,IN.tc0);

  // Reflection
  //const float Kr=0.5f;
  float4 envColor=texCUBE(envMap,IN.R);
  
  // Add reflection (not yet?)
  //baseCol=lerp(baseCol,envColor,Kr);
  //baseCol.rgb+=envColor.rgb*Kr;
//baseCol=envColor;

  // Lighting
  float3 ambient,diffuse,specular;
  LightingSun(Ke,Ka,Kd,Ks,shininess,lightDirection,lightColor,lightAmbient,IN.Position,IN.normal,eyePosW,
    ambient,diffuse,specular);
  float3 sdColor=baseCol*diffuse+specular;
  float3 ambientColor=baseCol*(ambient+Ke);
  //baseCol.rgb=baseCol*(ambient+Ke)+baseCol*diffuse+(specular*((int)outShadow.a));

  // Add reflection without fresnel (not really worth it for track objects)
  ambientColor+=envColor.rgb*Kr;

#ifdef CSM_MRT
  // Mix sky with texture color based on atmospheric influence
  outColor.rgb=lerp(skyColor,ambientColor,IN.extinction);
  //outShadow.rgb=lerp(skyColor,sdColor,IN.extinction);
  outShadow.rgb=sdColor*IN.extinction;
  outShadow.a=shadow;
  
  // Blending
  outColor.a=baseCol.a;
#else
  // Mix sky with texture color based on atmospheric influence
  outColor.rgb=lerp(skyColor,ambientColor+sdColor*shadow,IN.extinction);
  // Blending
  outColor.a=baseCol.a;
#endif
}
