some optimizations

[Normmatt]

this may improve speed somewhat "for(b=0;b<240;b++)" is slower than "for( b=240;b--; )" so if you use the "b--" instead of the b++ it should improve speed somewhat hope this helps

Edited January 21, 2005 by Normmatt

[Two9A]

this may improve speed somewhat "for(b=0;b<240;b++)" is slower than "for( b=240;b--; )" so if you use the "b--" instead of the b++ it should improve speed somewhat hope this helps

Just one problem, really; if you profile the application, you'll find that the bitmap-mode scanline renderer doesn't get called all that often; it's the CPU dispatch loop where all the time is lost. I can put that loop in, sure; just not sure it'll help much

Two Minutes Later: I tried it out on mode3, and it actually slowed things down. So maybe the compiler's doing a better job than I am?

Edited January 21, 2005 by Two9A

[Normmatt]

well it was worth a try ohh and i seen your resume why dont you rewrite the arm7 core in asm then it would run 2x as fast

[Two9A]

why dont you rewrite the arm7 core in asm then it would run 2x as fast

Dude. 1) It's mostly in asm already. 2) I can't write that stuff to save my life, so I'm not gonna touch the dispatch loop; I'd only slow it down.

[Federelli]

To these help?

 

Instead of:

xx = (x * x) * i;

yy = (y * y) * i;

zz = (z * z) * i;

xy = (x * y) * i;

yz = (y * z) * i;

zx = (z * x) * i;

 

Use:

 

xx1 = x ;

xy1 = y ;

yy1 = y ;

yz1 = z ;

zz1 = z ;

zx1 = z ;

for(m=1;m++;m<=x)

{ xx1 = xx1 + x ;

xy1 = xy1 + y ;

zx1 = zx1 + z }

for(m=1;m++;m<=y)

{ yy1 = yy1 + y ;

yz1 = yz1 + y ; }

for(m=1;m++;m<=z)

{ zz1 = zz1 + z ; }

 

for(m=1;m++;m<=i)

{ xx = xx + xx1 ;

xy = xy + xy1 ;

zx = zx + zx1 ;

yy = yy + yy1 ;

yz = yz + yz1 ;

zz = zz + zz1 ;

Edited January 22, 2005 by Federelli

[Two9A]

Instead of:

(12 muls)

Use:

(6 new variables, 4 loops and insane numbers of adds)

That'd work great for something like 6502, where there's no MUL instruction, Fed. Dunno where you want this code to go though; do tell which section you think could be improved by this

[Federelli]

I don't know really, all i know is this does optimize multiple rendering funcions in OpenGL .

So if you ever use that...