phong 光照模型。。

来源：互联网发布：照片卡通化软件编辑：程序博客网时间：2024/05/16 18:30

   前些日子乘着有闲功夫，慢慢的hlsl看了起来，发现以前学的数学知识全用上了，只可惜忘得都差不多了，又要恶补数学了。
   做了个比较简单的 phong 光照模型。

float4x4 Scal;
float4x4 World;
float4x4 View;
float4x4 projection;
float4x4 WorldViewProjection;
float3 EyePosition;
float3 LightDir;
float4 LightColor;

struct VertexInput
{
    float4  Position : POSITION;
    float2  Tex : TEXCOORD0;
    float3  Normal : NORMAL;
};

struct VertexOutput
{
    float4  Position : POSITION;
    float2    Tex    : TEXCOORD0;
    float3    Normal : TEXCOORD1;
    float3  View     : TEXCOORD2;
};

VertexOutput VertexMain(VertexInput input)
{
    VertexOutput output = (VertexOutput)0;

     WorldViewProjection = mul(mul(View, World), projection);

     output.Position = mul(mul(input.Position, Scal), WorldViewProjection);
     output.Tex = input.Tex;
     output.Normal = mul(input.Normal, World);
     output.View  = EyePosition - mul(input.Position,  World);

     return output;
}

float4 PixelMain(VertexOutput input) : COLOR0
{
    float diffsum;
    float specularsum;
    float4 color;
    float sunshinepower;
    float4 amibent = float4(0.1f, 0.1f, 0.1f, 1.0f);
    sunshinepower = 16.0f;

    diffsum = specularsum = 0;

    //漫反射
    LightDir = normalize(LightDir);
    diffsum = saturate(dot(LightDir, input.Normal));

    //镜面反射
    float3 L = -LightDir;
    float3 R = normalize(reflect(L, input.Normal));
    float3 V = normalize(input.View);

    specularsum = pow(saturate(dot(R, V)), sunshinepower);

    color = specularsum + diffsum * LightColor + amibent;


    return color;
}

technique techR
{
    pass p0
    {
        VertexShader = compile vs_2_0 VertexMain();
        PixelShader = compile ps_2_0 PixelMain();
    }
}

转自: http://www.cppblog.com/AstaTus/