Path: chuka.playstation.co.uk!news
From: "Alex Herbert" <alex@herbs.dabsol.co.uk>
Newsgroups: scee.yaroze.programming.2d_graphics
Subject: Re: What do'you mean I have to brush up on me maths!
Date: Wed, 14 Jul 1999 23:10:39 +0100
Organization: PlayStation Net Yaroze (SCEE)
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> ... and divide the higher value (shifted left a few bits for resolution)
by the
> lower. ...

Doh!  That's not right.  Should divide the lower value by the higher,
thereby keeping the result within a known range.


Oh, and here's that square root function:

asm u_short sqroot(u_long) {
    addu    v0,$0,$0
    ori        t0,$0,0x8000
    or         t1,v0,t0
L1:
    multu    t1,t1
    mflo      t2
    sltu       $at,a0,t2
    bne      $at,$0,L2
    srl         t0,t0,1
    addu    v0,t1,$0
L2:
    bne      t0,$0,L1
    or         t1,v0,t0
    jr          ra
    nop
}


If anyone has a quicker method, please let me know;  thanks.


Herbs