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hitzq

OpenGL ES some triangles flickering using OpenGL ES 2.0

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hitzq    113

hi all,

I have encountered a problem :
I draw a mount of triangles using OpenGL ES 2.0. Triangles drawn at the back, seem show in frames, then disappear in next frames, and then show again.

A friend told me that it’s because ParamBufferSize in powervr.ini is not enough. I googled parameter buffer, but still have no idea why this happens.

Is this because of the small ParamBufferSize?

Should I cut down the size of VBO? or DrawCall?

Thanks,

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hitzq    113
58 minutes ago, _Silence_ said:

It might be a depth issue. What projection matrix do you use ? How far are these triangles from the view point ?

Any errors reported by GLES maybe ?

hi _Silence_,

Thanks

The GL_DEPTH_TEST is disabled.

I have tried glGetError(), and it always return GL_NO_ERROR.

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_Silence_    969

Since you don't have any GL errors, you most probably don't exceed any max elements in the vertex arrays or size in the buffers.

I could find that reducing the chunks could help someone (see here). This would look weird to me, just like a broken GL implementation since you seem not to have any errors reported.

If this does not solve your problem, the issue can still come from many other things. And I advise to put far more information, and maybe some code (a little demo that reproduces the issue would also help, people could test it and check if they have the same problem).

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