[Render Monkey] Phong

[Render Monkey] Phong

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// Vertex Shader

float4x4 gWorldMatrix;
float4x4 gViewMatrix;
float4x4 gProjectionMatrix;

float4 gWorldLightPosition;
float4 gWorldCameraPosition;

struct VS_INPUT
{
    float4 mPosition : POSITION;
    float3 mNormal: NORMAL;
};

struct VS_OUTPUT
{
    float4 mPosition : POSITION;
    float3 mDiffuse : TEXCOORD1;
    float3 mViewDir: TEXCOORD2;
    float3 mReflection: TEXCOORD3;
};

VS_OUTPUT vs_main(VS_INPUT Input)
{
    VS_OUTPUT Output;

    Output.mPosition = mul(Input.mPosition, gWorldMatrix);

    float3 lightDir = Output.mPosition.xyz - gWorldLightPosition.xyz;
    lightDir = normalize(lightDir);

    float3 viewDir = normalize(Output.mPosition.xyz - gWorldCameraPosition.xyz);
    Output.mViewDir = viewDir;

    Output.mPosition = mul(Output.mPosition, gViewMatrix);
    Output.mPosition = mul(Output.mPosition, gProjectionMatrix);

    float3 worldNormal = mul(Input.mNormal, (float3x3)gWorldMatrix);
    worldNormal = normalize(worldNormal);

    Output.mDiffuse = dot(-lightDir, worldNormal);
    Output.mReflection = reflect(lightDir, worldNormal);

    return Output;
}

// Pixel Shader

struct PS_INPUT
{
    float3 mDiffuse : TEXCOORD1;
    float3 mViewDir: TEXCOORD2;
    float3 mReflection: TEXCOORD3;
};

float4 ps_main(PS_INPUT Input) : COLOR
{
   float3 diffuse = saturate(Input.mDiffuse);

   float3 reflection = normalize(Input.mReflection);
   float3 viewDir = normalize(Input.mViewDir);
   float3 specular = 0;
   if (diffuse.x > 0)
   {
      specular = saturate(dot(reflection, -viewDir));
      specular = pow(specular, 20.0f);
   }

   float3 ambient = float3(0.1f, 0.1f, 0.1f);

   return float4(ambient + diffuse + specular, 1);
}


// Stream Mapping
// 정점버퍼의 법선 시맨틱 NORMAL 추가로 Usage > NORMAL, FLOAT3 추가

// gWorldLightPosition
// 광원 위치

// gWorldCameraPosition 추가
// 카메라 위치