Move recycling of GpuImages to a lower abstraction layer

[emilwestergren]

Currently OpenGLPacked images (packed GpuImages) are recycled in the GpuContext they are created in. I suggest we move this recycling to a lower level (OpenGL texture level). This is more in sync with the recycling of ByteBuffer for RasterImages.

• The cost is some extra memory allocations every frame
• Will remove the need to modify private members like _coordinateSystem when recycling images
• Hides recycling from the "user layer"

@sebastianbaginski @simonmika opinions?

[ghost]

The cost is some extra memory allocations every frame

How much will it cost in terms of processing time per frame ?

Hides recycling from the "user layer"

I think it's a good idea.

[simonmika]

Go ahead. It is a good idea as we most likely will keep the luma part around for longer then the color.

[emilwestergren]

How much will it cost in terms of processing time per frame ?

Not that much, it's just the extra allocation and deallocation of object data for the high level images.

[marcusnaslund]

Is this issue still relevant? @emilwestergren

[emilwestergren]

Yes, but it's not urgent and it might not be possible with our current architecture.