For starters, it looks like you are just simply using bilinear filtering for those texture maps. Before you can use anisotropic filtering, you got to have trilinear filtering enabled (which is mipmapping). Are you creating mipmaps for your normal and specular maps? Do that first, then use anisotropic filtering. Antialiasing isn't going to help with this.

I wrote an example on how to use anisotropic filtering, but that HDD crapped out and I might have lost it for good =(

Shogun.

21st Century Moose

13,459

April 10, 2013 09:15 AM

You should definitely mipmap, use trilinear filtering, but in addition to that you should renormalize the normal map lookup result before putting it into your lighting calculation.

Direct3D has need of instancing, but we do not. We have plenty of glVertexAttrib calls.

Hodgman

52,717

April 10, 2013 09:16 AM

Yeah it looks simply like you're not using mipmapping, so when the texture is shrunk by more than 2x, bilinear filtering (which blends 4 texels) won't be able to stop it from shimmering.

. 22 Racing Series .

newObjekt

208

Author

April 10, 2013 05:44 PM

Yeah I'm not. I'll research that tonight. Thanks for pointing me in the right direction.

newObjekt

208

Author

April 12, 2013 12:06 AM

Alright I've got mipmap generation and Anistrophic filtering working and it's given very nice results.

http://inferno.codebrainshideout.net/Images/mipmaps%20a.png

Though I've noticed an odd issue. At extreme angles textures seem to turn completely black. I think this might be a specular problem? I'm not sure.

http://inferno.codebrainshideout.net/Images/mipmaps%20b.png - Wall at a normal angle.

http://inferno.codebrainshideout.net/Images/mipmaps%20c.png - Wall at a extreme angle.

Additionally I don't know what mhagain meant by "renormalize" the normal maps. Is that the same as calculating the tangent and binormal and applying those to the normal map?

-edit-

It's not a specular problem. It's a problem the tangent and binormals I think. I disabled normal maps but left specular maps enabled and the black faces effect was gone. But I noticed that the specularity was completely gone at the angles that caused the black faces.

newObjekt

208

Author

April 12, 2013 05:38 AM

Up to date frag and vert shaders:

http://inferno.codebrainshideout.net/Public%20Files/modelShader.frag

http://inferno.codebrainshideout.net/Public%20Files/modelShader.vert

And what my shaders look like.

http://inferno.codebrainshideout.net/Public%20Files/metal%20plate%20floor.shader

Sik_the_hedgehog

3,003

April 12, 2013 05:51 AM

"Renormalize" means you take the new value and normalize it (i.e. give it a length of 1). Essentially:


distance = sqrt(x*x + y*y + z*z);
x /= distance;
y /= distance;
z /= distance;

Well, you get the idea. Or you could just call normalize on the value within the pixel shader and let it do the job for you (though it burns up some more cycles in the GPU code).

Don't pay much attention to "the hedgehog" in my nick, it's just because "Sik" was already taken =/ By the way, Sik is pronounced like seek, not like sick.

21st Century Moose

13,459

April 12, 2013 09:13 AM

I note from your fragment shader code that you're already doing this, so nothing to worry about here.


vec3 tnormal = 2.0 * getTex(1, gl_TexCoord[0].st).rgb - 1.0;
tnormal = normalize (tnormal);

Direct3D has need of instancing, but we do not. We have plenty of glVertexAttrib calls.

newObjekt

208

Author

April 13, 2013 01:21 AM

I ended up solving my own problem with the "triangles turning completely black" problem. I had sunLocation set as a vec4 but was accidentally doing glUniform3f to send the coords to GLSL. Changed it and it fixed the problem.

Thanks for the help. :)

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