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View Full Version : Noob Question - Projection Mapping


sacslacker
02-23-2006, 05:38 PM
Hi guys,
Is there a way to do Triplanar projection (or something similar) in EI? I know I'm just missing something here.

NorthernLights
02-23-2006, 06:46 PM
Define: Triplanar
(and please don't say "Left as an exercise to the reader." ;)

Vizfizz
02-23-2006, 07:12 PM
Maya possesses both cubic and triplanar mapping. Here is maya's definition of triplanar.

Extrudes the texture along the axis defined by the maximum direction of the surface normal. The texture is projected much like fabric pulled around an arc. It also creates UV's based off of 3 separate projection planes.

Sacslacker:
EIAS has cubic mapping amongst other things. (Flat, spherical, cylindrical, & cubic) The program is capable of ulitizing UV coordinates if they a generated from an outside modeling package. It is unfortunate at this time that EIAS does not have its own internal UV editor. I think its mainly because of EIAS lack of an internal modeling subsystem. However, there are plenty of ways to apply textures in EIAS.

You also have these capabilities:



Select Polygons. This button is used to select polygons by clicking on individuals or drag a rectangle for multiples. Shift click to add or remove polygons within the selection. Ctrl-Clicking (Option-Clicking on Macintosh) on the Select Polygons button brings up a color picker that lets you change the color of selected polygons.



Fit to Selected Polygons. This button sets texture projection to the extent of the polygons selected with the Polygon Selection Button. There is a pulldown menu that is brought up by clicking on this button with the Ctrl-Key (Option-Key on Macintosh) held down. It brings up the following options:These options are designed to assist you when positioning cylindricaland spherical maps. Note that the button must be active in order for these options to be effective.


Also, you should checkout the plugin called Steamroller. www.tripledtools.com (http://www.tripledtools.com/) This lovely plugin will flatten out geometry so its more easily mapped with standard projection maps. Its a God send.

Vizfizz
02-23-2006, 07:17 PM
Check out this link:

http://www.electro303.com/electro303/05-bench-Art/Bench/004-SteamRoller/Steam15-US.html

sacslacker
02-23-2006, 09:13 PM
Thanks for explaining that! I guess this exposes one of my crutches when I'm being lazy (or more like pressed for time). In Maya I can use a triplanar projection to map an object and it handles scaling issues and seems to map the 2D texture fairly nicely around the object I'm mapping. I don't know if that makes sense. Basically its a handy utility node that allows me to wrap a 2d texture around background objects quickly with a decent result.

Thanks again for the link. I thinks its darn cool that you can just select polygons in EI and add a material to it. I wish it was that easy in every package!

sacslacker
02-23-2006, 09:46 PM
I wonder how hard it would be to add Triplanar as a projection type? I guess it boils down to how much it would get used. Is it just a matter of altering my habits or does anyone else think it'd be nice to have? Just curious.

Giacomo_M
02-24-2006, 03:15 PM
I wonder how hard it would be to add Triplanar as a projection type? ...or does anyone else think it'd be nice to have? Just curious.

Sounds great...I'd love to see it, although I'm not exactly sure what it is.

FYI: EIAS imports UV info from in other programs pretty well. If Triplanar projection is just Maya's name for a certain class of UV co-ordinates, you can probably map the model in Maya and export it to EI as an .obj.

GM

Vizfizz
02-24-2006, 03:17 PM
I wonder how hard it would be to add Triplanar as a projection type? I guess it boils down to how much it would get used. Is it just a matter of altering my habits or does anyone else think it'd be nice to have? Just curious.


Brian...

I'm a bit busy otherwise I'd do it myself. Can you provide the audience with an example from Maya of the benefits of this projection type?

Thanks

sacslacker
02-24-2006, 04:44 PM
Sure, I'll work something up tonight and post it.

sacslacker
02-25-2006, 04:00 AM
Ok, here is my little test. This is just a quick example so please don't laugh at me. =)

I've put an example of 3 projections I use often, TriPlanar, Cubic, and Planar. I made a little makeshift wall, duplicated it twice and then mapped the same texture using different projection types. With triplanar projection, it handles wrapping the texture evenly around the object on all sides. This set up took all of 2 minutes and is a single projection.

With the cubic and planar mappings you can clearly see distortions that would require another projection or other type of work to clean up. That is what I really like about triplanar projection mapping is I can very quickly map objects that aren't "hero" objects and put them in my scene quickly and easily. Of course, if this was an object that was getting a close up or required a lot of detail, I'd put a lot more work into the mapping. I'm just talking about objects in the distance and things like that. I hope that makes sense?

Basically I'm very new to EI so I was just curious if there was a projection type similar to the TriPlanar projection that can effectively map a texture like this with one projection. After the suggestions you guys posted, it seems that I'm thinking about this the wrong way. I should be dealing with UV editing inside another package which, honestly is not a big deal. Anyways, I thought I'd post this just to demonstrate what I feel is a cool projection type, my buddy, TriPlanar.

As always, feel free to call me a noob and throw tomatoes at me. Actually, it's Friday of a very long week so feel free to throw some beer my way! =)

I hope this example makes sense :shrug:

Reuben5150
02-25-2006, 09:22 AM
In EI using a planar texture projected as "cubic" would give the same results as your "triplanar" example :-)


Reuben

Reuben5150
02-25-2006, 09:46 AM
Cubic mapping in EI -http://www.btinternet.com/~reuben.flounders/images/cubicmap.jpg

But, i suspect maya's Triplanar mapping would also make the top of the wall seamless ?, hence the name "triplanar" :)

sacslacker
02-25-2006, 10:24 AM
Yep, it does seem to but I have to say, EI's cubic seems to yield better results than Maya thats for sure. Either that or I'm doing it wrong. Thanks!

Giacomo_M
02-25-2006, 05:07 PM
The "cubic" mapping you posted from Maya looks an awful lot like a cubic *environment* map--it's distorted around the edges in the way an environment map would be.

My guess is that a setting exists in Maya for the standard, non-distorted cubic mapping (like the sample Reuben posted.) It's just too basic a thing to *not* be in there somewhere.

GM

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