PDA

View Full Version : tree question

markw7
06-25-2003, 05:10 AM
help

I'm looking for a quick solution for trees in a Complete scene without buying a plug-in. Lots of trees will be planted. I'm exploring a "billboard" approach that rotates a plane towards the camera as the camera moves (mel? standard "look-at" constraint?), a paintfx tree, and the one below.

I've currently got two planes textured with the same image map at 90 degrees to each other. Looks fine in shaded view (6), because of the texture "blend" setting I think, but not in a render or ipr view. Does anyone know a way to achieve the look on the left in a final render, by manipulating the blend of the two textures perhaps, or the lights on them? Sorry if I sound like a doofus.

http://www.urban-interface.com/mark/temp/tree.jpg
misterdi
06-25-2003, 05:56 AM
Looking at the render result, it seems that one plane doesn't receive light as much as the other plane.

Try to balance the ambient and color value of the material, it might be necessary to bring down the color value to a low value and increase the ambient all the way up.
I would connect the same image files to both, and insert a set range node or multiply/divide node to adjust the output value.

You might want to use incandesence too, but be carefull with non black background on your image files.

There is also a tutorial in the net, I think it's using ray-diffuse plug-ins to get some self-shadowing on the tree. Try to search with ray diffuse keyword.

Best regards,
markw7
06-25-2003, 02:54 PM
It doesn't all make sense yet but thanks for the tips.

I found this on a great site of tutorials by Olivier Renouard which looks like your suggestion:

www.drone.org/tutorials/lighting_flat_objects.html

woe my brain
misterdi
06-26-2003, 04:13 AM
Yes that's the tutorial that I thought would be applicable to your problem.

Best regards,
BigSky
06-26-2003, 11:30 AM
might also be worth searching "normal maps" in here...nice discussion.
MasonDoran
06-26-2003, 03:04 PM
r u rendering your objects double sided? it just looks like the normal is facing the wrong direction on one of the faces....


also, if you map the texture to the incandescence and not the color attribute....it will render without light/shadow information so u can get the fully saturated object.
markw7
06-26-2003, 05:34 PM
Thanks guys!

First, 2bytes, the polys were set to doublesided. Their normals were pointing away from the camera but reversing them didn't resolve anything.

Based on the other suggestion, in the image below I've mapped "the texture to the incandescence and not the color attribute". I also followed a tip by misterdi "to balance the ambient and color value of the material ... to bring down the color value to a low value and increase the ambient all the way up". It reads better.

http://www.urban-interface.com/mark/temp/tree2.jpg

re: misterdi's other suggestion, I inserted a multiply/divide node to the color and ambient attribute and then back to the file. Not sure about my graph network so I included it below. I guess the tree is darker because it still relies on the scene lighting while the first solution doesn't (?).

http://www.urban-interface.com/mark/temp/tree3.jpg
http://www.urban-interface.com/mark/temp/tree3network.jpg

You can still read the angling of the second plane, which is undesirable. Can I adjust the muliply/divide node so that the textures blend more?

Hope I understood the comments. Both suggestions seem to improve the basic display of the texture. I'm leaning towards eliminating the crossing poly and trying out a constraint to the camera as it moves. I'm worried about it lookin goofy though.
CGTalk Moderation
01-15-2006, 12:00 PM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.