Shader "Cg normal mapping" {
Properties {
_BumpMap ("Normal Map", 2D) = "bump" {}
_Color ("Diffuse Material Color", Color) = (1,1,1,1)
_SpecColor ("Specular Material Color", Color) = (1,1,1,1)
_Shininess ("Shininess", Float) = 10
}
SubShader {
Pass {
Tags { "LightMode" = "ForwardBase" }
// pass for ambient light and first light source
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#include "UnityCG.cginc"
uniform float4 _LightColor0;
// color of light source (from "Lighting.cginc")
// User-specified properties
uniform sampler2D _BumpMap;
uniform float4 _BumpMap_ST;
uniform float4 _Color;
uniform float4 _SpecColor;
uniform float _Shininess;
struct vertexInput {
float4 vertex : POSITION;
float4 texcoord : TEXCOORD0;
float3 normal : NORMAL;
float4 tangent : TANGENT;
};
struct vertexOutput {
float4 pos : SV_POSITION;
float4 posWorld : TEXCOORD0;
// position of the vertex (and fragment) in world space
float4 tex : TEXCOORD1;
float3 tangentWorld : TEXCOORD2;
float3 normalWorld : TEXCOORD3;
float3 binormalWorld : TEXCOORD4;
};
vertexOutput vert(vertexInput input)
{
vertexOutput output;
float4x4 modelMatrix = _Object2World;
float4x4 modelMatrixInverse = _World2Object;
// unity_Scale.w is unnecessary
output.tangentWorld = normalize(
mul(modelMatrix, float4(input.tangent.xyz, 0.0)).xyz);
output.normalWorld = normalize(
mul(float4(input.normal, 0.0), modelMatrixInverse).xyz);
output.binormalWorld = normalize(
cross(output.normalWorld, output.tangentWorld)
* input.tangent.w); // tangent.w is specific to Unity
output.posWorld = mul(modelMatrix, input.vertex);
output.tex = input.texcoord;
output.pos = mul(UNITY_MATRIX_MVP, input.vertex);
return output;
}
float4 frag(vertexOutput input) : COLOR
{
// in principle we have to normalize tangentWorld,
// binormalWorld, and normalWorld again; however, the
// potential problems are small since we use this
// matrix only to compute "normalDirection",
// which we normalize anyways
float4 encodedNormal = tex2D(_BumpMap,
_BumpMap_ST.xy * input.tex.xy + _BumpMap_ST.zw);
float3 localCoords = float3(2.0 * encodedNormal.a - 1.0,
2.0 * encodedNormal.g - 1.0, 0.0);
localCoords.z = sqrt(1.0 - dot(localCoords, localCoords));
// approximation without sqrt: localCoords.z =
// 1.0 - 0.5 * dot(localCoords, localCoords);
float3x3 local2WorldTranspose = float3x3(
input.tangentWorld,
input.binormalWorld,
input.normalWorld);
float3 normalDirection =
normalize(mul(localCoords, local2WorldTranspose));
float3 viewDirection = normalize(
_WorldSpaceCameraPos - input.posWorld.xyz);
float3 lightDirection;
float attenuation;
if (0.0 == _WorldSpaceLightPos0.w) // directional light?
{
attenuation = 1.0; // no attenuation
lightDirection = normalize(_WorldSpaceLightPos0.xyz);
}
else // point or spot light
{
float3 vertexToLightSource =
_WorldSpaceLightPos0.xyz - input.posWorld.xyz;
float distance = length(vertexToLightSource);
attenuation = 1.0 / distance; // linear attenuation
lightDirection = normalize(vertexToLightSource);
}
float3 ambientLighting =
UNITY_LIGHTMODEL_AMBIENT.rgb * _Color.rgb;
float3 diffuseReflection =
attenuation * _LightColor0.rgb * _Color.rgb
* max(0.0, dot(normalDirection, lightDirection));
float3 specularReflection;
if (dot(normalDirection, lightDirection) < 0.0)
// light source on the wrong side?
{
specularReflection = float3(0.0, 0.0, 0.0);
// no specular reflection
}
else // light source on the right side
{
specularReflection = attenuation * _LightColor0.rgb
* _SpecColor.rgb * pow(max(0.0, dot(
reflect(-lightDirection, normalDirection),
viewDirection)), _Shininess);
}
return float4(ambientLighting + diffuseReflection
+ specularReflection, 1.0);
}
ENDCG
}
Pass {
Tags { "LightMode" = "ForwardAdd" }
// pass for additional light sources
Blend One One // additive blending
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#include "UnityCG.cginc"
uniform float4 _LightColor0;
// color of light source (from "Lighting.cginc")
// User-specified properties
uniform sampler2D _BumpMap;
uniform float4 _BumpMap_ST;
uniform float4 _Color;
uniform float4 _SpecColor;
uniform float _Shininess;
struct vertexInput {
float4 vertex : POSITION;
float4 texcoord : TEXCOORD0;
float3 normal : NORMAL;
float4 tangent : TANGENT;
};
struct vertexOutput {
float4 pos : SV_POSITION;
float4 posWorld : TEXCOORD0;
// position of the vertex (and fragment) in world space
float4 tex : TEXCOORD1;
float3 tangentWorld : TEXCOORD2;
float3 normalWorld : TEXCOORD3;
float3 binormalWorld : TEXCOORD4;
};
vertexOutput vert(vertexInput input)
{
vertexOutput output;
float4x4 modelMatrix = _Object2World;
float4x4 modelMatrixInverse = _World2Object;
// unity_Scale.w is unnecessary
output.tangentWorld = normalize(
mul(modelMatrix, float4(input.tangent.xyz, 0.0)).xyz);
output.normalWorld = normalize(
mul(float4(input.normal, 0.0), modelMatrixInverse).xyz);
output.binormalWorld = normalize(
cross(output.normalWorld, output.tangentWorld)
* input.tangent.w); // tangent.w is specific to Unity
output.posWorld = mul(modelMatrix, input.vertex);
output.tex = input.texcoord;
output.pos = mul(UNITY_MATRIX_MVP, input.vertex);
return output;
}
float4 frag(vertexOutput input) : COLOR
{
// in principle we have to normalize tangentWorld,
// binormalWorld, and normalWorld again; however, the
// potential problems are small since we use this
// matrix only to compute "normalDirection",
// which we normalize anyways
float4 encodedNormal = tex2D(_BumpMap,
_BumpMap_ST.xy * input.tex.xy + _BumpMap_ST.zw);
float3 localCoords = float3(2.0 * encodedNormal.a - 1.0,
2.0 * encodedNormal.g - 1.0, 0.0);
localCoords.z = sqrt(1.0 - dot(localCoords, localCoords));
// approximation without sqrt: localCoords.z =
// 1.0 - 0.5 * dot(localCoords, localCoords);
float3x3 local2WorldTranspose = float3x3(
input.tangentWorld,
input.binormalWorld,
input.normalWorld);
float3 normalDirection =
normalize(mul(localCoords, local2WorldTranspose));
float3 viewDirection = normalize(
_WorldSpaceCameraPos - input.posWorld.xyz);
float3 lightDirection;
float attenuation;
if (0.0 == _WorldSpaceLightPos0.w) // directional light?
{
attenuation = 1.0; // no attenuation
lightDirection = normalize(_WorldSpaceLightPos0.xyz);
}
else // point or spot light
{
float3 vertexToLightSource =
_WorldSpaceLightPos0.xyz - input.posWorld.xyz;
float distance = length(vertexToLightSource);
attenuation = 1.0 / distance; // linear attenuation
lightDirection = normalize(vertexToLightSource);
}
float3 diffuseReflection =
attenuation * _LightColor0.rgb * _Color.rgb
* max(0.0, dot(normalDirection, lightDirection));
float3 specularReflection;
if (dot(normalDirection, lightDirection) < 0.0)
// light source on the wrong side?
{
specularReflection = float3(0.0, 0.0, 0.0);
// no specular reflection
}
else // light source on the right side
{
specularReflection = attenuation * _LightColor0.rgb
* _SpecColor.rgb * pow(max(0.0, dot(
reflect(-lightDirection, normalDirection),
viewDirection)), _Shininess);
}
return float4(diffuseReflection + specularReflection, 1.0);
}
ENDCG
}
}
}
