This commit clears framebuffers when they are created, copies the contents of
the previous framebuffer to the new framebuffer when resizing and moves all the
resizing code into the blit method. All of these help to reduce screen
corruption, although a small amount still remains if you resize quickly.
This fixes latency (and also screen corruption when resizing), as we blitted a
framebuffer that had already been displayed on the off-screen window rather
than the one that had just been rendered.
A long-term goal is to write clean room implementations of these
libraries, for several reasons:
* The original libraries are missing, so we currently have to do a fair
amount of awkward bytecode patching in the loader to use JOGL
instead.
* The original libraries were not compiled for 64-bit Linux. We might
also want to compile for new architectures (e.g. ARM or RISC-V) or
additional operating systems (e.g. the BSDs).
* I'm worried that over time the libraries will bit rot and might
eventually stop working with modern JREs - it's already been about 10
years since they were originally compiled!
I'm not too concerned about putting this in the main open-source
repository: I think it's generally believed that interfaces are not
copyrightable, and we're only copying the interface for
interoperability purposes. The native code will be original.
Furthermore, most of the jaggl interface is just a copy of the OpenGL
interface, so it's unlikely that Jagex could claim they hold the
copyright on it anyway.