Texturing Models

[Peregrinati]

Hi - following the tutorials and I'm wondering if the BasicShader provided is supposed to show textures on models that have them included in the file? I can't get it to, even though when I set a breakpoint and check the line:

Code:

myDevice.Textures[0] = ((BasicEffect)part.Effect).Texture;

works properly - at least the value of "Texture" is a texture of the same dimensions as the one the model uses - but the texture is not being rendered. From what I can tell by looking at the shader code, the texture should be displayed (I am, however, very new at this), but something is wrong somewhere.

I also tried modifying things so that textures can manually be set on models (giving the Model two asset strings, one for the model and one for the texture, and setting myDevice.Textures[0] to a Texture2D loaded in LoadContent) - but that didn't work either.

[Peregrinati]

Ok, I figured it out... kinda. If you look at this code:

Code:

float4 BasicShader(PS_INPUT Input) : COLOR0 {
    float3 Normal = normalize(Input.Normal);
    float3 ViewDirection = normalize(Input.ViewDirection);
    LightDirection = normalize(-LightDirection);
   
    float EdgeComponent = dot(Normal, ViewDirection);
    float3 TotalAmbient = saturate(AmbientColor * EdgeComponent);

    float NDotL = dot(Normal, LightDirection);
    float3 DiffuseAverage = (DiffuseColor + LightDiffuseColor) * 0.5f;
    float3 TotalDiffuse = saturate(DiffuseAverage * NDotL);
   
    float3 Reflection = normalize(2.0f * Normal * NDotL - LightDirection);
    float RDotV = max(0.0f, dot(Reflection, ViewDirection));
    float3 TotalSpecular = saturate(LightSpecularColor * pow(RDotV, SpecularPower));

>>>>float4 TextureColor = (Input.Color.rgba + 1) * tex2D(TextureSampler, Input.Texcoord);<<<<
    float4 LightingColor = float4(TotalAmbient + TotalDiffuse + TotalSpecular, 1.0f);
   
    return TextureColor > 0 ? TextureColor * LightingColor : LightingColor;
}

I figured that TextureColor was always <=0, and I was right. I did some further testing and discovered that it's always 0 because Input.Color.rgba is always 0, but I don't understand why. If I add 1 to it before multiplying it by tex2D(TextureSampler, Input.Texcoord) (see the highlighted line of code), then my textures are displayed, although with errors (both using the built in model textures, and the tweak I made for setting the model texture in the engine). I don't think this is a nice solution though - how would I go about setting it in the engine? I suppose I could pass a color in as a parameter to the shader, but I don't know what I'd call it... what exactly does the Input.Color : COLOR0 come from, and what is it supposed to do?

Thanks

[Peregrinati]

Ok, forget adding 1 - thought about it for a second and that's the same thing as just removing the Input.Color.rgba from the TextureColor assignment. And I said it displays perfectly, but not really - there's a bunch of speckles on the texture... kind of like parts of it are inverted or something strange. :S Any ideas?

[mikeschuld]

I might have you zip the whole deal up and send it to me so I can play with it. Much easier to debug things that way

[Peregrinati]

Ok, it was too big to put on the forum attachment, so I sent it to the hotmail address you have in your profile... hope that's ok.