Orthographic Zdepth for displacement

[CJI]

I have used the Zdepth render element hundreds of times and thought i knew it pretty well. Anyway, im trying to create a tileable displacement map of roof tiles using the common method of modelling the tiles then using a top down camera in ortho projection mode to render out a zdepth pass. Well i just cant get this this to work! and im almost pulling my hair out because by all accounts it should be working!

 

If i untick the ortho projection box i do get a zdepth pass. Although it does seem to be very centred for some reason? Im pickled over this one, I googled and searched but didn't find anything other than a comment on the area that wasn't resolved. any thoughts??

 

I will post a picture of the "centred Depth map". all the tiles are on a flat plane.

[CJI]

[ATTACH=CONFIG]38028[/ATTACH]

This is what i get with the Ortho box unticked on top down camera. I get just black when it is ticked.

 

This is the model.

[ATTACH=CONFIG]38029[/ATTACH]

[Bruce Hart]

Hey Curtis,

Perhaps you just need to re-check the ZDepth min and max distance you have going there. I turn on show environment ranges with the camera to work out what the values are. I got the same centered effect with a perspective camera, but the ZDepth worked just fine with ortho on - provided the ranges were correct.

[Nic H]

i would just use a falloff material in diffuse set to distance blend and render a top/side view?

[Bruce Hart]

i would just use a falloff material in diffuse set to distance blend and render a top/side view?

 

...an even better idea.

[CJI]

Thats the thing, i used the environment ranges to get the right distances for the min max, thats why its annoying me so much as it should be working.

 

I've done it Nics way before for a large scene as the zdepth element max distance was capped far before the max distance i wanted to put in, i just wanted to see if anyone else has had this ortho issue before.

 

Strange...

 

Thanks for the reply guys.

[CJI]

ok that doesn't work either. i think it has something to do with my cameras Z axis (viewing direction). couldn't say what it is. The falloff appears in perspective mode, and if i choose any other axis in the map settings (although its white of course). So the material is doing its job, it seems to be the camera.

 

EDIT: oh and ive tried both target and free cameras with same results, im at a loss here.

[CJI]

Turns out it doesn't work with Mental Ray. Who'd have thought it!

 

Switched to scanline and i'm zdepthing away again.

[Peter M. Gruhn]

And _I_ use a gradient ramp and a cylindrical uvw. I think it needs tweaking a bit, try setting the grad's coords to vw. Use "fit" on the mapping to make it exactly as tall as is your geometry. Then just a hair bigger if you get wrap at the extremes.