[mikefran]

can anyone tell me why, when making a series of polygons (I am making a car wheel with spokes) some of the polygons are not visible in the perspective screen while others are. They are made by joing points and hitting "P" key. The polygons appear in every other window except the perspective. I have tried importing the object into Layout but they don't appear there either

Help!!!!!

[Johnny9ball]

You need to Flip them.

If you select the points clockwise and hit p the polygon will face you. If you select them counterclockwise they will face away, and if they face away they have no back an you cant see them unless you rotate the prespective view around them, or flip them by selecting them and hitting f.

[twisteddragon]

As Johnny said. You must click clockwise. If you do click counter by accident. Either make them double sided. Or press "f" to flip it.

If you select points using the front, top, or side view wireframes. remember you select all the points on that line deep. So if you try to form a poly"p" you could end up with weird shaped sides and so on.

[Johnny9ball]

As a general rule you should not make the Polygons doublesided because when you render the object then it will have to render both sides of the polygon therefore increasing the rendertime. The only reason you would make a polygon doublesided is if the other side needs to be rendered to be seen. Most objects are closed like a ball so you would not make the polygons doublesided because the inside of the object would never be seen dureing rendering, unless you fly the camera inside it or for some reason opened it in an animation or blew it up.

[twisteddragon]

Yeah. but with a very small object. like a hundred or so polys, double siding really wont increase the render time all that much.

But i could see where you would get a problem if you had several thoughsand.

I never use double sided unless i need to now that i know how to flip polies.

[Kvaalen]

Double sided polygons can also cause black spots when you subpatch them (in Layout).

If you do have double sided polygons, just make sure nothing is selectd, and type: Shift + z (or click on "merge polys").
if you have a whole bunch of polygons facing one way and others facing another way, instead of selecting them manually, just select all those polygons and click on "align" (under the details tab).

You can also make polygons double sided by clicking on "Double sided" in the surface editor.