Another Z-fighting question

Hakken · 14 Oct 2008, 14:35

SO, two more questions on my fight with Z-fighting. I've dug through the models I had flickering issues with and did have quite a few faces sharing planes, most of them in separate groups, which I thought would protect them from clashing. I went ahead and got rid of all of those faces, and am still seeing some flickering. Thanks in advance for any advice you can give.:

Is it possible that faces that are near each other, not on top of each other, but only close to each other, can be Z-fighting? I see through some surfaces to other surfaces that are close to the surfaces in the forefront, most often when I'm zoomed out quite a bit. Sometimes some images that are a good 2 - 3" in front of a surface can disappear altogether.
Does an image count as a surface when imported into a drawing? I've laid many images on top of surfaces I've created and then get my flickering affect. Should I be putting these images in as textures only? I hope not, as some of these images need to exist on their own (have transparent backgrounds, etc.)

Thanks again, Jonah

boofredlay · 14 Oct 2008, 15:10

If you could post up the model I am sure you could get much more help.
I would be happy to take a look see as I am sure many others here would too.

CraigD · 14 Oct 2008, 15:56

@hakken said:

Is it possible that faces that are near each other, not on top of each other, but only close to each other, can be Z-fighting? I see through some surfaces to other surfaces that are close to the surfaces in the forefront, most often when I'm zoomed out quite a bit. Sometimes some images that are a good 2 - 3" in front of a surface can disappear altogether.

It's hard to answer this one without seeing a model. You can sometimes get z-fighting like flicker if faces are very close together though.

@hakken said:

Does an image count as a surface when imported into a drawing? I've laid many images on top of surfaces I've created and then get my flickering affect. Should I be putting these images in as textures only? I hope not, as some of these images need to exist on their own (have transparent backgrounds, etc.)

Yes an image is a face within a group. You should be adding these as textures if they are to be placed on an existing face. You may need to do some Photoshop work if you are trying to place an image with an alpha channel onto an existing texture image.

If you post the model, I'm sure you'll get help from lots of folks.

Cheers,

 - CraigD

Hakken · 14 Oct 2008, 16:18

Thanks for the help so far. I have been unable to get approavl to post the model up here from my client, so I'll have to re-create the issue I'm having with a new model, and the deadlines I'm on are giving me little time to do that. I do have some free time coming up tho, so I should be able to whip something up that I can post.

Thanks.

Gaieus · 15 Oct 2008, 07:09

Hi Hakken,

for your problem # 1:
Yes, indeed, faces very close to each other can indeed flicker from a certain ditance. In SU, in order to display things correctly, the "distance" between faces must be at least one pixel (since it is a vector based program, however the output will be raster based).
Now if you zoom out enough so that your 2 or 3 inches occupy less screen space than 1 pixel, the Z fighting will be apparent. You can however export in higher resolution and hope that it won't be seen.

This is the same with lines showing through fairly thin walls.

Question # 2:
Yes, indeed, your imges placed right on top of faces will also flicker. If you didn't have the issue with transparency, you could turn them into components cutting holes but with transparency this would "hide" the wall face behind the transparent parts as well which is probably not your goal.

The only olution in this case would be to make these wall texture unique, eport them and edit them in an image editor adding the images you want to apply (see example attached)

Hakken · 23 Oct 2008, 19:33

Hey, just wanted to drop a quick note and say thanks for the tips on this. Through being very diligent about how I placed my images (as textures, not images), and by re-setting my views so I'm not so far away that the camera thinks separate planes are the same, I was able to eliminate the flickering problem completely.

Thanks a ton to all for your help and insight! I appreciate it muchly.