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OpenGL Simple 3dModels displays, but more complex ones don't. Memory limit, buffer size, etc... ?

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Hello,

I have recently created an importer which loads Blender 3D generated models into my under-development iphone app.

For simple objects such as cube, cone, etc... it works perfectly fine. However, as soon as the objects reach a certain degree of complexity such as a donut shape , sphere; the engine display only a part of the objects; e.g half of it; sometimes less. I have checked the vertices and indices in the data model and they are perfectly fine.

It looks like there would be a hard limit such as a number of vertices, memory allocation etc...but i can't exactly figure it out. As i am not yet quite confident in OpenGL ES there might be quite a direct answer to this problem ; but hasn't found it yet.


Any pointer, tips are more than welcome to draw the second half of this sphere ;)

Cheers,
Stéphane
PS. some screenshots to complement this post:

The model in Blender:
[attachment=7038:Blender Initial Sphere.png]

The model in the Iphone simulator; as you can see quite not the same:
[attachment=7039:Iphone Sphere.png]

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I made some applications for iPhone with more complex geometry 8000+ poly (just for testing) and it works correct
There should be problem with your allocations in VBO (indexes probably) which should be OK for simple objects like cube in front view
- check your index count and vertex count in VBO creation state
- also check for quads vs. triangles (index count from 4 to 6), are you exporting direct triangles?

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Problem solved: the number of the indices didn't deal with the vertex indice array but another array. Once it has fixed ; it works perfectly fine ! Big Thanks !

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