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OpenGL ES Display problem, is it memory data corruption ?

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Hi !

I have a drawing problem, display seems to be corrupted.

The program is opengl es 3.0 running on iPhone.

I have a file loader and it loaded data correctly before, but if you look at both attached images, the red, blue and green cubes aren't displayed correctly ( and only them).

I haven't changed the source code of my loader, so I don't think it comes from it.

I know however one thing, it is that vertices and indices ( and texture coordinates, and normals ) are raw pointers, and I think my problem is in relation to memory data/heap corruption because I didn't freed them before.

The scenes were displayed correctly before and this problem came suddenly, without changing the source code for the loader and the opengl es class.

What do you think about this problem ? Can you help me to solve it ?

Screen Shot 2017-11-11 at 21.18.47.png

Screen Shot 2017-11-11 at 21.20.27.png

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