# DX11 DX11 - Wierd texture appearance combined with tessellation...

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Hi guys!

Thanks to you I got the tessellation working, and for now It's working great, but!

I'm having a small problem with textures, as the title suggests. What I do is that I send a simple variable to the shader, called uv_scale (float), which represents the, well, the uv scale. (texture_coordinate * factor). But, when I use this factor, the texture itself is ONLY visible when close up, and if I take the camera far enough away, it dissapears!

With UVSCALE:

output.Diffuse = float4(saturate(t_map.Sample(ss, input.texcoord*uv_scale).rgb*10.0f), 1.0f);

// I time by 10 so that the texture appears brighter, for now...



But without (just removing the *uv_scale), the texture appears all over the mesh, could it be the sampler state?

D3D11_SAMPLER_DESC sd;
sd.Filter = D3D11_FILTER_ANISOTROPIC;
sd.MaxAnisotropy = 2;
sd.BorderColor[0] = 0.0f;
sd.BorderColor[1] = 0.0f;
sd.BorderColor[2] = 0.0f;
sd.BorderColor[3] = 0.0f;
sd.MinLOD = 0.0f;
sd.MaxLOD = FLT_MAX;
sd.MipLODBias = 0.0f;



Now I put the title "tessellation", because in fact I tesselate the sphere, and the actual tesselation works, but just not the texture sampling (well it's not good enough)...

Calculation of texCoords (Domain Shader, I believe this is good enough, but i'm not sure)

uvwCoord.x * patch[0].texcoord + uvwCoord.y * patch[1].texcoord + uvwCoord.z * patch[2].texcoord;


Pics:

CLOSE UP:

FAR:

Thanks as usual!

-MIGI0027

Edited by Migi0027

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What are the types of the variables input.texcoord and uv_scale?  Perhaps you have a type mismatch which is causing unexpected behavior...

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input.texcoord -> float2

uv_scale         -> float

Edited by Migi0027

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Sorry for all the trouble I caused our little brains.

The problem was external, meaning that how the resource itself was filled.

But thanks!

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Introduction:
In general my questions pertain to the differences between floating- and fixed-point data. Additionally I would like to understand when it can be advantageous to prefer fixed-point representation over floating-point representation in the context of vertex data and how the hardware deals with the different data-types. I believe I should be able to reduce the amount of data (bytes) necessary per vertex by choosing the most opportune representations for my vertex attributes. Thanks ahead of time if you, the reader, are considering the effort of reading this and helping me.
I found an old topic that shows this is possible in principal, but I am not sure I understand what the pitfalls are when using fixed-point representation and whether there are any hardware-based performance advantages/disadvantages.
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