Render Height map?

[SUPERGENIUS]

Hello, it's me again with the zillion questions.

We are a game studio looking for ways to creatively use phoenix for games. One thing we need to do is render out a height map of the water created by phoenix so we can use it for distortion maps for more realistic game water. This is proving to be a bit difficult however, due to the nature of cameras and zdepth.

Here is an image.

What I need to do is render a zdepth or height map without the darkening in the corners. It's darkening because of the distance change from the lens across the image, and I get that. Is there some way to turn this off? Or.. is there another way I should do this to get the result I want?

I considered setting my camera way way far away and zooming but seems like a bad solution. Anyone have any ideas?

Also tried render to texture but it doesn't like it. Thanks for any tips!

AJ

[Ivaylo Katev]

interesting question
what about to put the camera above the water and to export the z channel?

[LarsSonparsson]

What about planar mapping water from the side with gradient? That way you could have "height map" as a texture.

[Paul Oblomov]

Hope to make vray vector displacement mod to get a map from phx...

[SUPERGENIUS]

Excellent ideas fellas. The image I posted is actually a zdepth rendered from vray, but as you can see the edges get a bit dark. When you say export the zchannel... did you mean zdepth? I apologize for the misunderstanding if the zchannel is different from zdepth.

IF I planar mapped it from the side, that may not work out because its the ripples and little wakelets that I was hoping to capture for distortion in UDK. But maybe I misunderstand... is there something I can do there?

Thank you all for your time and patience,
AJ

[Ivaylo Katev]

well, use parallel projection to avoid this, when i tested the idea i did it automatically without any thoughts what exactly is stored in the frame buffer, the depth or the distance. the parallel projection makes them equal

[SUPERGENIUS]

Interesting. I'm new to the concept, I assume that means that you just create a camera that is very far away and zoom in so that there is almost a parallel projection? Or is there a switch somewhere in the F10->Vray->Camera options?

At work we use vray 1.5, but I also own it at home in 2.0 form if that is necessary. Thanks again for your help.

Edit: I was thinking maybe I could just render from an ortho view and use the exposure control.

[Ivaylo Katev]

yes, an ortho view does the trick

[SUPERGENIUS]

The more I learn about 3D (and it's been 12 years) the more I come to the conclusion that simplicity is the key. Thank you for your help here, this worked well.