4 replies to this topic

[kruseborn]

Am trying to write diffuse light to a texture in uv coordinates.
My vertex shader look like this:

output.pos = float4( (input.tex.xy * 2.0) - 1.0, 0.5, 1.0);

If am trying to read from this texture later:

float3 res = texLightMapUV.Sample(LINEAR_CLAMP, input.tex);
return float4(res, 1.0f);

Am getting a small error, its lookes like the texture is too small for the object. So I was thinking it was some kind of offset error when am writing to the texture. So i was trying with:

float offset = (1.0/1024.0)*0.5;
input.tex.xy += offset;
//input.tex.xy -= offset;
//input.tex.xy += float2(offset, -offset);

When i do this its looks better but its not ok,
Am using directx 10.

[rouncer]

try clamping the texture

[kusma]

Could you post a screen-shot?

[kruseborn]

I find the problem, when I was writing to a new texture in texture space I just writing color to the pixels just inside the coordinates. Then when am reading from it i get aliasing problem. Because some pixels are black. When i was reading from a normal texture the picture is always a little bit bigger then the coordinates.

I solved it by doing a dilation filter after.

[kusma]

Ah, yes. Common problem :)