An issue with tessellation a model with DirectX11
- by Paul Ske
I took the hardware tessellation tutorial from Rastertek and implemended texturing instead of color. This is great, so I wanted to implemended the same techique to a model inside my game editor and I noticed it doesn't draw anything. I compared the detailed tessellation from DirectX SDK sample. Inside the shader file - if I replace the HullInputType with PixelInputType it draws. So, I think because when I compiled the shaders inside the program it compiles VertexShader, PixelShader, HullShader then DomainShader. Isn't it suppose to be VertexShader, HullSHader, DomainShader then PixelShader or does it really not matter?
I am just curious why wouldn't the model even be drawn when HullInputType but renders fine with PixelInputType.
Shader Code:
[code]
cbuffer ConstantBuffer
{
float4x4 WVP;
float4x4 World; // the rotation matrix
float3 lightvec; // the light's vector
float4 lightcol; // the light's color
float4 ambientcol; // the ambient light's color
bool isSelected;
}
cbuffer cameraBuffer
{
float3 cameraDirection;
float padding;
}
cbuffer TessellationBuffer {
float tessellationAmount;
float3 padding2;
}
struct ConstantOutputType {
float edges[3] : SV_TessFactor;
float inside : SV_InsideTessFactor;
};
Texture2D Texture;
Texture2D NormalTexture;
SamplerState ss {
MinLOD = 5.0f;
MipLODBias = 0.0f;
};
struct HullOutputType {
float3 position : POSITION;
float2 texcoord : TEXCOORD0;
float3 normal : NORMAL;
float3 tangent : TANGENT;
};
struct HullInputType {
float4 position : POSITION;
float2 texcoord : TEXCOORD0;
float3 normal : NORMAL;
float3 tangent : TANGENT;
};
struct VertexInputType {
float4 position : POSITION;
float2 texcoord : TEXCOORD;
float3 normal : NORMAL;
float3 tangent : TANGENT;
uint uVertexID : SV_VERTEXID;
};
struct PixelInputType {
float4 position : SV_POSITION;
float2 texcoord : TEXCOORD0; // texture coordinates
float3 normal : NORMAL;
float3 tangent : TANGENT;
float4 color : COLOR;
float3 viewDirection : TEXCOORD1;
float4 depthBuffer : TEXTURE0;
};
HullInputType VShader(VertexInputType input)
{
HullInputType output;
output.position.w = 1.0f;
output.position = mul(input.position,WVP);
output.texcoord = input.texcoord;
output.normal = input.normal;
output.tangent = input.tangent;
//output.normal = mul(normal,World);
//output.tangent = mul(tangent,World);
//output.color = output.color;
//output.texcoord = texcoord; // set the texture coordinates, unmodified
return output;
}
ConstantOutputType TexturePatchConstantFunction(InputPatch inputPatch,uint patchID : SV_PrimitiveID) {
ConstantOutputType output;
output.edges[0] = tessellationAmount;
output.edges[1] = tessellationAmount;
output.edges[2] = tessellationAmount;
output.inside = tessellationAmount;
return output;
}
[domain("tri")]
[partitioning("integer")]
[outputtopology("triangle_cw")]
[outputcontrolpoints(3)]
[patchconstantfunc("TexturePatchConstantFunction")]
HullOutputType HShader(InputPatch patch, uint pointId : SV_OutputControlPointID, uint patchId : SV_PrimitiveID)
{
HullOutputType output;
// Set the position for this control point as the output position.
output.position = patch[pointId].position;
// Set the input color as the output color.
output.texcoord = patch[pointId].texcoord;
output.normal = patch[pointId].normal;
output.tangent = patch[pointId].tangent;
return output;
}
[domain("tri")]
PixelInputType DShader(ConstantOutputType input, float3 uvwCoord : SV_DomainLocation, const OutputPatch patch)
{
float3 vertexPosition;
float2 uvPosition;
float4 worldposition;
PixelInputType output;
// Interpolate world space position with barycentric coordinates
float3 vWorldPos = uvwCoord.x * patch[0].position +
uvwCoord.y * patch[1].position +
uvwCoord.z * patch[2].position;
// Determine the position of the new vertex.
vertexPosition = vWorldPos;
// Calculate the position of the new vertex against the world, view, and projection matrices.
output.position = mul(float4(vertexPosition, 1.0f),WVP);
// Send the input color into the pixel shader.
output.texcoord = uvwCoord.x * patch[0].position +
uvwCoord.y * patch[1].position +
uvwCoord.z * patch[2].position;
output.normal = uvwCoord.x * patch[0].position +
uvwCoord.y * patch[1].position +
uvwCoord.z * patch[2].position;
output.tangent = uvwCoord.x * patch[0].position +
uvwCoord.y * patch[1].position +
uvwCoord.z * patch[2].position;
//output.depthBuffer = output.position;
//output.depthBuffer.w = 1.0f;
//worldposition = mul(output.position,WVP);
//output.viewDirection = cameraDirection.xyz - worldposition.xyz;
//output.viewDirection = normalize(output.viewDirection);
return output;
}
[/code]
Somethings are commented out but will be in place when fixed. I'm probably not connecting something correctly.
