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diginime
05-28-2006, 12:44 PM
Hi guys, i think maybe i'm asking a silly question here...can anyone tell me what is the difference between revolution along axis and revolution along curve? By the way, is there a Center Pivot option in XSI ? Besides, how to import picture to XSI? I mean image plane. I saw some tutorial using rotoscope, some using grid...but i dunno how they do it..can anyone teach me?Thanks.

dwigfor
05-28-2006, 05:57 PM
Lot of questions for a single post.. :)

There's two types of pivots - a temporary one, and then the mesh's permanent center. Permanent one is used when you don't have COG enabled on the right toolbar. An easy way to adjust the temporary one is to hold alt and move it where you need it. For the permanent one, try Transform/Move Center to Bounding Box. Then you can select Center and move it where you need it. That's necessary when you want to Symmetrize polys.

I've never used Rev around Axis. I think that works with Poly Meshes. Rev around curve works if you draw a curve and want to spin it, like making a vase, lightbulb, etc. Search the online docs-I'm sure they have a much better explanation than mine...

Importing images. I think there's a script on xsibase to load in different pictures of a car and it set up image planes. Might be helpful.. To do it yourself: Create a new clip (under render tab-3) and select the image you want to import. Make note of the dimensions of it. Get/Poly/Grid and set the subds to 1,1 and change the length to match your dimensions (if it's 1600x1200, I usually do 16x12 so it's not gigantic). Apply a constant material to it. Hit 7 to bring up render tree. Load your clip in and connect it to the constant color. Apply a XZ projection to the texture node. In explorer, I open up the Display properties and change it to Texture Detail for all (change the first and hit the button at the bottom of the ppg). Then, in your viewport, uncheck the override button at the top-that let's you view different display types together-ie, You can model in wireframe and still see your image plane. Lastly, branch select (mdl click) the grid (so you also get the texture projection) and scale,rotate,translate your image to where you want it.

Sbowling
05-29-2006, 12:24 AM
Lot of questions for a single post.. :)


And they are all covered in the manual or easy to find with a simple search of these forums.

ThE_JacO
05-29-2006, 01:37 AM
I've never used Rev around Axis. I think that works with Poly Meshes. Rev around curve works if you draw a curve and want to spin it, like making a vase, lightbulb, etc. Search the online docs-I'm sure they have a much better explanation than mine...

you're a bit confused yourself :)
revolution around axis means that the points are duplicated and connected at regular intervals by transforming them around an axis. This is the classic revolution/lathe process you are describing used for vases, lightbulbs etc, this generates a shape symmetrical on two axes normally.

revolution around a curve will not revolve around just one vector, but for each point in the section description (normally a curve) will take the closest point on the curve and revolve around the tangent to the curve, which is very similar to revolving around an axis and then deforming by a curve, this produces a mesh that usually has no symmetries in it (except for topological ones obviously)

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