HLSL Effect Examples in Visual Studio .NET

Generating QR in Visual Studio .NET HLSL Effect Examples

11

= = = = =

{ { { { {

0.5f, 0.1f, 0.9f, 1.0f, 1.0f,

0.5f, 0.0f, 0.9f, 0.9f, 1.0f,

0.5f, 0.0f, 1.0f, 0.8f, 1.0f,

}; }; }; }; };

// // // // //

// material reflectivity float4 k_a = { 0.8f, 0.8f, 0.8f, 1.0f }; float4 k_d = { 0.4f, 0.4f, 0.4f, 1.0f }; float4 k_s = { 0.1f, 0.1f, 0.1f, 1.0f }; int n = 32; // transformations float4x3 WorldView : WORLDVIEW; float4x4 Projection : PROJECTION;

// // // //

struct VS_OUTPUT { float4 Pos : POSITION; float4 Diff : COLOR0; float4 Spec : COLOR1; }; VS_OUTPUT VS( float3 Pos : POSITION, float3 Norm : NORMAL, float Occ : TEXCOORD0, uniform bool bHemi, uniform bool bDiff, uniform bool bSpec) { VS_OUTPUT Out = (VS_OUTPUT)0; // diffuse direction float3 L = -DirFromLight; // hemisphere up axis float3 Y = -DirFromSky; // position (view space) float3 P = mul(float4(Pos, 1), (float4x3)WorldView); // normal (view space) float3 N = normalize(mul(Norm, (float3x3)WorldView)); // reflection vector (view space) float3 R = normalize(2 * dot(N, L) * N - L); // view direction (view space) float3 V = -normalize(P); float4 Amb = k_a * I_a; float4 Hemi = k_a * lerp(I_b, I_c, (dot(N, Y) + 1) / 2) * (1 - Occ); float temp = 1 - max(0, dot(N, L)); float4 Diff = k_d * I_d * (1 - temp * temp); float4 Spec = k_s * I_s * pow(max(0, dot , V)), n/4); float4 Zero = 0;

(continued)

// position (projected) Out.Pos = mul(float4(P, 1), Projection); // diffuse + ambient/hemisphere Out.Diff = (bDiff Diff : 0) + (bHemi Hemi : Amb); // specular Out.Spec = (bSpec Spec : 0); } return Out; } technique THemisphere { pass P0 { VertexShader = compile vs_1_1 } } technique THemisphereDiffuse { pass P0 { VertexShader = compile vs_1_1 } } technique THemisphereDiffuseSpecular { pass P0 { VertexShader = compile vs_1_1 SpecularEnable = TRUE; } } technique TAmbient { pass P0 { VertexShader = compile vs_1_1 } } technique TAmbientDiffuse { pass P0 { VertexShader = compile vs_1_1 } } technique TAmbientDiffuseSpecular {

VS(true, false, false);

VS(true, true, false);

VS(true, true, true);

VS(false, false, false);

VS(false, true, false);

11

pass P0 { VertexShader = compile vs_1_1 VS(false, true, true); SpecularEnable = TRUE; } }

We learned earlier that an effect can declare certain variables with specific names, semantics, or annotations to work well with EffectEdit. Here are the specific variables that the hemisphere effect uses so that EffectEdit will recognize them:

string XFile = "SkullOcc.x"; int BCLR = 0xff202080; // transformations float4x3 WorldView : WORLDVIEW; float4x4 Projection : PROJECTION; // model // background

These variables provide the model name in XFile, the background color in BCLR, the world-view transform in WorldView, and the projection transform in Projection. The rest of the global variables and the shader function can be named anything. Now let s see how the shader actually works. Here s the shader:

struct VS_OUTPUT { float4 Pos : POSITION; float4 Diff : COLOR0; float4 Spec : COLOR1; }; VS_OUTPUT VS( float3 Pos : POSITION, float3 Norm : NORMAL, float Occ : TEXCOORD0, uniform bool bHemi, uniform bool bDiff, uniform bool bSpec) {

(continued)

VS_OUTPUT Out = (VS_OUTPUT)0; // diffuse direction float3 L = -DirFromLight; // hemisphere up axis float3 Y = -DirFromSky; // position (view space) float3 P = mul(float4(Pos, 1), (float4x3)WorldView); // normal (view space) float3 N = normalize(mul(Norm, (float3x3)WorldView)); // reflection vector (view space) float3 R = normalize(2 * dot(N, L) * N - L); // view direction (view space) float3 V = -normalize(P); float4 Amb = k_a * I_a; float4 Hemi = k_a * lerp(I_b, I_c, (dot(N, Y) + 1) / 2) * (1 - Occ); float temp = 1 - max(0, dot(N, L)); float4 Diff = k_d * I_d * (1 - temp * temp); float4 Spec = k_s * I_s * pow(max(0, dot , V)), n/4); float4 Zero = 0; // position (projected) Out.Pos = mul(float4(P, 1), Projection); // diffuse + ambient/hemisphere Out.Diff = (bDiff Diff : 0) + (bHemi Hemi : Amb); // specular Out.Spec = (bSpec Spec : 0); return Out; }

The shader takes several input arguments and returns the outputs using the VS_OUTPUT structure. Three of the input arguments come from the vertex buffer, including the position, the normal, and an occlusion factor. It s obvious that these parameters come from the vertex buffer because they have semantics.

float3 Pos : POSITION, float3 Norm : NORMAL, float Occ : TEXCOORD0,