I'm new to programming shaders in HLSL. Originally I had this shader doing normal mapping, but I want to do a diffuse texture on the object. If your not sure how diffuse works but can see the error with the code i'd be really happy just to know the syntax error if there is one, because I can't find it. here is the code: (if you need more information then what i've provided please let me know, any help would be appreciated. thx :D /* Normal mapping shader This shader performs a per-pixel dot3 bump mapping lighting effect with only the diffuse light component calculated. */ // global matrices uniform extern float4x4 g_matWVP; uniform extern float4x4 g_matWI; // light direction in world space uniform extern float3 g_lightDir; // textures uniform extern texture g_texture; uniform extern texture g_normalMap; // colour texture sampler sampTexture = sampler_state { Texture = <g_texture>; MinFilter = LINEAR; MagFilter = LINEAR; MipFilter = LINEAR; AddressU = WRAP; AddressV = WRAP; }; // normal texture sampler sampNormalMap = sampler_state { Texture = <g_normalMap>; MinFilter = LINEAR; MagFilter = LINEAR; MipFilter = LINEAR; AddressU = WRAP; AddressV = WRAP; }; // vertex shader input that allows position and texture coordinates as well as TBN struct VSInput { float3 pos: POSITION0; float3 tan: TANGENT0; float3 bin: BINORMAL0; float3 nor: NORMAL0; float2 tex: TEXCOORD0; }; // vertex shader output struct VSOutput { float4 pos: POSITION0; float3 lightDir: TEXCOORD0; float2 tex: TEXCOORD1; }; // normal mapping vertex shader VSOutput VS_NormalMapping(VSInput a_Input) { VSOutput output; // calculate homogenous position output.pos = mul(float4(a_Input.pos, 1.0f), g_matWVP); // copy texture coordinates across output.tex = a_Input.tex; // calculate matrix to tangent space float3x3 toTangentSpace = transpose(float3x3(a_Input.tan, a_Input.bin, a_Input.nor)); // calculate light's direction relative to tangent space float3 lightDirL = mul(float4(g_lightDir, 0.0f), g_matWI).xyz; output.lightDir = mul(lightDirL, toTangentSpace); return output; } VSOutput VS_DiffuseTexture(VSInput a_input) { VSOutput output; //in VS i believe i only need to calculate the vertex's normal since in the other pass the other vertex calulation is done output.nor = mul(float4(a_input.nor,0.0f),g_matWI).xyz; return output; } // normal mapping pixel shader float4 PS_NormalMapping(VSOutput a_Input) : COLOR { // index into textures float4 colour = tex2D(sampTexture, a_Input.tex); float3 normal = tex2D(sampNormalMap, a_Input.tex); // convert normal from (0 - 1) to (-1 - 1) normal = (normal - 0.5f) * 2.0f; // normalize light direction float3 light = normalize(a_Input.lightDir); // calculate diffuse component float diffuse = max(dot(normal, light), 0.0f); // return texture colour modified by diffuse component return (colour * diffuse); } float4 PS_DiffuseTexture(VSOutput a_Input): COLOR { //diffuse properties float3 dLightColor = {0.8,0.8,0.8}; float3 dMaterialColor = {0.7,0.6,0.5}; //make diffuse intensity matrix float3 dIntensity = mul(dLightColor,dMaterialColor); float dVariable = max(dot(g_lightDir,a_Input.nor),0.0f); float3 diffuse = dVariable * dIntensity; return float4(diffuse,a_Input.a); } technique NormalMappingTech { pass P0 { vertexShader = compile vs_2_0 VS_NormalMapping(); pixelShader = compile ps_2_0 PS_NormalMapping(); } pass P1 { vertexShader = compile vs_2_0 VS_DiffuseTexture(); pixelShader = compile ps_2_0 PS_DiffuseTexture(); } }