metamax

This is probably more of a math question than a Max question but.. how are quadratic equations handled for graphics applications?

I have been learning jit.expr and genexpr by porting a bunch of Bourke's geometry equations.. with amazing success considering my lack of math chops. I mean really… my math sucks, though most wouldn't suspect as much considering my new found love for expr and my success in porting a variety of equations into Max.

(x^2 +3) (y^2 +3) (z^2 +3) - 32(xyz+1) = 0

http://paulbourke.net/geometry/kusnerschmitt/

Seems very straightforward.. yet, regardless of format, the following approach obviously doesn't work - unless I want to output 

expr (pow($f1,2)+3.)*(pow(f$2,2)+3.)*(pow($f3,2)+3.)-32.*($f1* $f2*$f3+1.)

jit.expr @expr (pow(in[0].p[0],2)+3.)*(pow(in[0].p[1],2)+3.)*(pow(in[0].p[2],2)+3.)-32*(in[0].p[0]* in[0].p[1]*in[0].p[2]+1.)

expr out1 = (pow(in1.r,2)+3)*(pow(in1.g,2)+3)*(pow(in1.b,2)+3)-32*(in1.r*in1.g*in1.b+1)

I assume I need to break the equation down into three separate equations that solve for x, y and z respectively, no? So while I brush up on my algebra, are there any online calculators that do this?

I guess my parents were right when they told me to pay attention in math class.

This is probably more of a math question than a Max question but.. how are quadratic equations handled for graphics applications?   

I have been learning jit.expr and genexpr by porting a bunch of Bourke's geometry equations.. with amazing success considering my lack of math chops.  I mean really… my math sucks, though most wouldn't suspect as much considering my new found love for expr and my success in porting a variety of equations into Max.

Seems very straightforward.. yet, regardless of format, the following approach obviously doesn't work - unless I want to output nothing…  

I assume I need to break the equation down into three separate equations that solve for x, y and z respectively, no?  So while I brush up on my algebra, are there any online calculators that do this?

I guess my parents were right when they told me to pay attention in math class.


porting-quadratic-equations

I didn't look at the link, but that's an equation that needs to be 

 (the '= 0' bit at the end gives that away) rather than an equation representing a direct relationship between an input and an output.

but I did notice a typo in the expr version:

edit: sorry I just read the last bit of your post-- to solve that equation you'd need to do some pretty advanced maths-- and it may even be unsolvable-- you could try isolating terms but I believe that doesn't necessarily work for 3-term polynomials. You may need to use other advanced techniques. Sorry, not much help.

I didn't look at the link, but that's an equation that needs to be solved (the '= 0' bit at the end gives that away) rather than an equation representing a direct relationship between an input and an output.
but I did notice a typo in the expr version:
f$2 should be $f2

edit: sorry I just read the last bit of your post-- to solve that equation you'd need to do some pretty advanced maths-- and it may even be unsolvable-- you could try isolating terms but I believe that doesn't necessarily work for 3-term polynomials. You may need to use other advanced techniques. Sorry, not much help.


that would be a nice job for the next weekend

that would be a nice job for the next weekend
http://paulbourke.net/geometry/
:)


porting quadratic equations?