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OpenGL Multi-threading with Opengl question

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Just wondering, I tried running a separate thread for my LoadGame routine, where I load new textures, load the map, etc... I want to run it in a thread so that I can draw a progress bar at the same time, among others. The problem is that, both threads have call to opengl. The LoadGame routine creates some texture so I get to do a few gl calls there and meanwhile the main thread use some gl drawing operations. It seems that when I load my game with a thread, once the game is loaded all the in game textures are white, I debugged in to see what was the problem and all texID''s of my textures had impossible values, so im guessing something in glGenTexture goes wrong. Is there any way I could do this? Besides not using a thread?

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If you want to use threads, you need to know about synchronization. Read up on mutexes.


How appropriate. You fight like a cow.

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quote:
Original post by mannam
OpenGL is not thread-safe. Textures loaded in a thread are not accessible by other threads
What''s your source for this? While GL calls are certainly not reentrant, I see no reason why textures from one thread wouldn''t be usable by another thread.


How appropriate. You fight like a cow.

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You could load you''re textures into memory in you''re second thread and then transfer them to OpenGL in the same thread that you created you''re GL context after they''ve been loaded.

Having said that, I really don''t see the need to use multiple threads just to have a progress bar. Unless the files are ridiculously large, update the bar between loading each file should be regular enough.

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