.3ds issues with not enough vertexes

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3 comments, last by _Lopez 16 years, 2 months ago
I am not sure what the topic is called, but with a simple cube that has 12 polygons, I want it to have 24 vertices, so my code can have a normal for each vertex, should be 3 normals. With Milkshape3D it is saving the cube out as 20 vertexes. When I render the model I show the normals and without a doubt there are 20 normals, but I want 24. The top of the box has 3 per vertex and the bottom has only 2 per vertex. Why is this? I can't tell Milkshape3D to export it as 24 either it always saves as 20. Would 3DStudio allow me to control this better? Do I need to change my code to fix this? If so, what do I need to do. Thanks
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Sorry, most probably I didn't uderstand something, but if you want separate normals for each vertex, shouldn't the cube have 36 vertices (3 for each polygon, for two triangles per face, for 6 faces)? You would need 24 vertices if you used polygons with 4 vertices instead than triangles, but then your cube would be composed by 6 polygons, and not 12 as you say. In addition, I'not really sure that 3ds format can handle polygons different than triangles...
Hi cignox1,

What I did to get the required normals for the cube to look right, and again this is just showing that .3ds format isn't for me eventually, I made the simple cube in Milkshape3D, but I made each triangle and formed a quad and then copied each quad and rotated and moved each quad till I made a cube, then exported that, and now I have 24 vertices, that show 3 normals per vertex. Why this is so hard for people to understand is beyond me, I want to see the normal facing in each direction, for each vertex that would be 3 directions, because that vertex 3 sides to work with.

Anyway once this project is done I am dumping .3ds, for something else. I just wanted to find if my code was sane, and it is, just need the mesh to come in with the correct amount in the first place.
I don't know where the problem originates, but if you decided to use another format anyway, then you could test your code with a 'hand made' cube:

-1 1 -1 //First face upper left vertex
0 0 -1 //First face upper left normal
1 1 -1 //First fasce upper right vertex
0 0 -1 //First face upper right normal
-1 -1 -1 //First face lower left vertex
0 0 -1 //First face lower left normal
1 -1 -1 //First face lower right vertex
0 0 -1 //First face lower right normal

And then repeate for every face, adjusting coordinates as needed.
Whats the big problem?

All you need to do in studio max is...
1. create a cube.
2. apply edit mesh.
3. choose faces, and select all.
4. right click the cube, and choose detach.
5. now you have 6 unique faces for the cube, with no shared vertices on more than one face.

simple.

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