#define VS_SHADERMODEL vs_4_0_level_9_1
#define PS_SHADERMODEL ps_4_0_level_9_1

//-----------------------------------------------------

matrix World;
matrix View;
matrix Projection;

//-----------------------------------------------------

struct VertexShaderInput
{
    float4 Position : SV_POSITION;
    float3 Normal : NORMAL0;
};

struct VertexShaderOutput
{
    float4 Position : SV_POSITION;
    float4 Color : COLOR0;
};

//-----------------------------------------------------

VertexShaderOutput MainVS(in VertexShaderInput input)
{
    VertexShaderOutput output = (VertexShaderOutput)0;

    float4 worldPosition = mul(input.Position, World);
    float4 viewPosition = mul(worldPosition, View);
    output.Position = mul(viewPosition, Projection);

    float4 N = mul(input.Normal, World); // normal in world space
    float3 L = normalize(float3(0, 1, 0)); // light direction
    float4 diffuse = dot(L, N) * float4(1,1,1,1); // dot * light color

    output.Color = saturate(diffuse);

    return output;
}

float4 MainPS(VertexShaderOutput input) : COLOR
{
    return saturate(input.Color);
}

//-----------------------------------------------------

technique Phong
{
    pass P0
    {
        VertexShader = compile VS_SHADERMODEL MainVS();
        PixelShader = compile PS_SHADERMODEL MainPS();
    }
};