[SDL] Best way to implement a simple "Framebuffer"

[nils.stec]

Changing the update routine to this (swapped x/y and removed the calculating of the address) got me about 50fps on my Phenom, not bad, but should be more ;)

Code:

addr = 0x200;
for(y = 0; y < 32; y++) {
	for(x = 0; x < 32; x++) {
		set_px(x,y, get6502memory(addr));
		addr++;
	}
}                



Accessing the memory via get6502memory is necessary, because of portability and for the use in other planned emus/changing the output interface. if i access the memory directly by it's pointer it makes ~~ +20fps.

Next step should be the use of a lookup table for colors, but this gets me a weird gfx output....:

this is what it looks like with my switch/case:
[Image: http://s2.postimage.org/2kfveu1wk/gfx_switchcase.jpg ] (http://postimage.org/image/2kfveu1wk/)

And this is with the lookup table (code following):
The skier starts to skiing and goes upwards instead of downwards. it seems the y coordinates is "negative", i don't understand, i simply changed from boxRGBA to boxColor. The wrong colors can be, i think i have some mistakes inside the lut...
[Image: http://s2.postimage.org/kaj2klw38/gfx_colorlut.png ] (http://www.postimage.org/)


After i get this working i will change the code to use a 32x32 surface and use rotozoom to zoom it by factor 8.

No pixel sizes are hardcode, i think, everything should be done with #defines, i want to compile it for my mobile later, so everything needs to be portable ;)[/img]

------------------------
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http://krumeltee.wordpress.com/




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