Strange UV error
Hi.
I am hoping any of you know what´s going on here.
I am using 3dsmax 2012 and have a weird error.
I have Unwrapped a 3d model, and up close in 3dsmax it looks correct.
But when I zoom out in the editor I get lines at the edges of the model, it´s like the texture/UV moves/scales when I zoom out.
Anyone have any ideas on how to fix this?
I am hoping any of you know what´s going on here.
I am using 3dsmax 2012 and have a weird error.
I have Unwrapped a 3d model, and up close in 3dsmax it looks correct.
But when I zoom out in the editor I get lines at the edges of the model, it´s like the texture/UV moves/scales when I zoom out.
Anyone have any ideas on how to fix this?
Replies
Not only that, but you need enough padding between your uv islands. If your islands are only 1 pixels apart it will work at 2048, but mip down to 512 or even 1024 and you'll start to have issues.
Good rule of thumb is probably about 16 pixels between uv islands at 2048, 8 at 1024, 4 at 512 or so.
Also, if you have a black material right next to a white material, you want even more padding between islands, and make sure your background isn't black. I turn up the "edge padding" on my bakes to like 64 pixels or something to get rid of as much background as I can.
Just so you know, I am mapping the objects in my scene to an atlas with 9 different textures. Some of them needs to be mapped like a tiled texture, so if I have to use padding to compensate, it will be almost impossible to get the desired results.
Is there any way to save the vertex position on the bitmap?
Ex. vertex 1 position is between pixel 2 and 3 (x) and between 2 and 3 (y).
If I could do this then padding would not be necessary.
There are other things you can do as well as padding - make sure any texture islands near each other are similar colours. Also, for tileable textures you should subdivide your image by splitting it down the middle in to four quadrants, then again to 16 etc., so that when your texture is downresed you get the minimum bleed.
if it's a tiled texture , is n't there an option to 'clamp' the texture so you don't get that 1 pixel bleed.
long time since I have done this stuff with blitz 3d engine, can't find an option like this in max.
Do you know what mip-mapping is?
Kurt Russell Fan Club - from what i remember if you are tiling a texture map , the clamp just means you dont get a 1 pixel black line around the texture.
i am not tech savvy enough to exaplin it any further:)
I believe the issue is mips, especially if malicesmash is tiling 9x9. Here's what you'll get when your texture mips in a non-power of two texture atlas:
It looks like rubbish because of the way mipmap creation halves the texture size each lower LOD
This is what you get when you try and tile a clamped (as opposed to wrapped) texture:
And yes, I do know what mip-mapping is.
But it is not the solution I want.
Let´s say I have an atlas (512x512) with 2x2 textures. I want to map 1 polygon (square) on to one of the textures in the atlas, v1: 0x0, v2: 256x0, v3: 256x0, v4: 256x256 (a perfect square). What I want to do now is to clamp the lines to that texture in the atlas so all mip-mapping go inwards and not destroying the edges between the different textures in the atlas.
It´s kind a hard to explain because English is not my main language.
The problem in this case is not so much the mipping (though it contributes), but the filtering.
http://udn.epicgames.com/Three/TerrainAdvancedTextures.html
There will always be a slight bleed, even with a few tricks to pad those tiles by a couple of pixels.
If you do crack it though - let me know! I spent a bit of time looking at this a while back and ended up discarding the approach.
The simplest way I found was to resize the 1024 atlas to 128 and then map it on the models. Then switch back to the 1024 atlas, and it looks good enough.