Output RAW mode during render rather than PNG at the end of the render.

[rquadling]

One of the nice things with XaoS is the ability to render large images. https://drive.google.com/drive/u/0/folders/1T8XqPW2Jjlmeu5R87QaBmyjlq-Lv56Ki for example.

What I'd like to do is generate a MUCH larger one 2880ppi A0.

Which comes out at a silly size of 134816 x 93537 which currently breaks XaoS.

$ xaos -render Fractalastica.xpf -size 134816x93537 -saveimg Fractalastica.png
Processing command line options

 Saving image... 0.00% XaoS(11784,0x10b325dc0) malloc: can't allocate region
:*** mach_vm_map(size=18446744073434935296, flags: 100) failed (error code=3)
XaoS(11784,0x10b325dc0) malloc: *** set a breakpoint in malloc_error_break to debug

Is there any possibility of outputting the image in RAW mode as it is rendered? This should help reduce the memory usage for such an insane size image.

Converting a RAW image to PNG/TIFF is then upto me. And yes. I know this will be 35GB file (assuming 8bit per channel RGB). But that's why RAW output mode would be far easier to post-process that having XaoS have to handle it.

[kanurag94]

Dulicate of #77