Android: OpenGL: glGenTextures not working in constructor?

Question

Can anyone tell me why glGenTextures() isn't working in my constructor?

Here is how my project is setup:

• A custom renderer is used which calls .draw on the current active stage.
• When a stage is created it assigns itself (the end line of its constructor) to the static Global.activeStage.
• Now the renderer calls .draw on the currently active stage which reference is kept inside Global.activeStage.
• In the stage I have a function which loads all textures that are needed in the stage.
• If I call this function the first time .draw is called there is no problem.
• If I call it in the constructor though, everything works except glGenTextures() - it creates a zero value rather than 1..2..3 and so on.
• In both cases a global GL10 reference is used rather than the one .draw gets, so it's not the problem.

It seems as if everything works ONLY if there is already a reference to the current stage I'm using (if the stage is created e.g. the constructor has already run).

I am not sure if it is related, but the stage is created in a Thread after onCreateSurface ends.

I could post some of the code if you say which parts would be relevant.

Answer 1

I am quite sure you have to run all openGL operations on the Thread associated with openGL. This is why it works when called from your draw() method called from the renderer (which runs on the GL-Thread) but not from the constructor (which runs on another Thread as you say).