# JoryRFerrell

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1. ## File formats which export texture mappings from 3d CAD software?

Well.....EMBARASSING. I overlooked how the texture coords are stored in obj file. I expected coords to be in .mtl file, not .obj. NEEEEEVEEEEEEERMIND.
2. ## File formats which export texture mappings from 3d CAD software?

I need to know of some formats which export texture maps so I can simply parse that and avoid having to hand map a texture to my models. I tried figuring out how .mtl files store their texture mapping. However, they just seem to reference the texture rather than recording the actual mapping. Any suggestions?
3. ## Determine if vert normal moves into or out of geometry by finding if verts cw/ccw?

I figured out a method and posted a vid on it:   http://youtu.be/wwMD2UX0rQ4
4. ## Determine if vert normal moves into or out of geometry by finding if verts cw/ccw?

Yea, I already know about cross-product method. I have made one, but Newell's Method is more accurate.   Like I was saying, my method grabs all neighboring verts, and forms a projected face from them on each axis. For each created face, I find the normal of the face via the cross product method. Then with all those calculated face normals, I take the average and I end up with the more accurate per-vertex normal. My problem was correctly finding the neighbor vertices in a consistent clockwise/counter-clockwise order. They often get reversed with my current algorithm. But, if I could find a way to correctly determine the order of the verts after finding them, I could simply reverse the per-vertex normal whenever it was facing the wrong direction. However I found a way to ensure the normal is facing the correct direction no matter what, and I don't need to determine the handedness of the neighbor verts order to do it. Look at explanation below.
5. ## Help learning how to structure code efficient and flexible

I do the same thing with pen and paper. There is something different about HOLDING a set of physical objects and solving the problem with them, that seems to make problems less complex. Makes sense considering how the brain works I guess.

7. ## Determine if vert normal moves into or out of geometry by finding if verts cw/ccw?

Yes. Objects are guaranteed to be closed (for now) and must account for both convex and concave geometry. Is their an algorithm which will do this for both with a single equation? Or would it require different equations/logic-branches for each?   Also, I want it to handle weird geometry with verts forming concave shapes which bow in past the objects local origin. Say you take a unit cube a split two opposite faces, along the z axis, into four faces each. then you take the center vertices of those four faces and translate them both -1.5 along the z axis. You'd have one vert which went inwards (forming a concave surface) past its own origin, so I can't rely on a vector from the origin to each vert, that compares with the generated normal to check the total angle between the two or something.
8. ## Determine if vert normal moves into or out of geometry by finding if verts cw/ccw?

<p>How do I determine if a the normal for a vertex has been created by ccw ordered verts or cw wound verts? I assign each vert's neighbors to a list in the order they wind around, but it doesn't assign them in a secific clockwise/ccw order consistently. I have just decided to calculate the normal then determine whether the verts are cw, or ccw, and then change the signs of the normal vector components accordingly.</p> <p>&nbsp;</p> <p>Some suggested using a secondary vector to compare the angle between the secondary and the generated normal. If greater than 90, or less than, that would tell me if the normal vector is facing the direction I need. But I don't think this works for concave (NOTE: I originally wrote &quot;CONVEX&quot;. I meant &quot;CONCAVE&quot;. :\) shapes (normals can face toward origin, allowing for angles less than 90 degrees when compared with a vector drawn from the origin of object.</p>
9. ## OpenGL Pyopengl Problem: Little confusion as to how to reset newly created objects position to default (0.0,0.0,0.0).

Bit late...but ty. I ended up getting the answer before you replied. TY for notes though, as you did help with a few issues.
10. ## Why are my cubes randomly rotating a few seconds into animation?

Also, as for the ground_1 object rendering weirdly....I screwed up the order of the verts. Instead of writing them in the order they appeared in the face, I simply wrote each verts in the order they appeared in list of all verts. The result was that the last 2 verts are actually supposed to be switched, but I failed to do so. So IT WAS rendering properly, just not how I expected it to. :P
11. ## Why are my cubes randomly rotating a few seconds into animation?

Cool beans. You answered my question and you helped me a lot with the info on Push and Pop funcs. I had read about them but I didn't really pay attention. Patience is not my strong suit. :P As for calling rotation before translation, it wasn't intentional, but I didn't really care. I have read in the bookmthat provided a large part of this code, that you should rotate before translation because trans affects rotation, but for now, I was just worried about fooling around with rots. As for the diff between rotatef and rotated, I have noticed no I'll effect's in the program.   TY for your help!