i have decided to make this page a place where i can dump some tips and insights i have found during my work.

some of them are quick book grabs :)
 

btw,
if you "doubt" the problems, just take a look at this screenshot.
it's supposed to continue to get brighter (duh), but it clamps.
precision clamping problems in action! this can't be fixed though ;/
 

if you don't have to use float, then dont!!!
use int, and often you don't even need that much storage, 32 bits isnt' a lot these days, but still.
for the network layer it is..
use short if you can.

and geting episilon might take a few tries,... so do your self a favor and check out other people's source code.
moller has a good source code example of collision up at his site, david eberly, and ditto with goutshalk's.
they all have good numerical stuff at there sites. goutshalk wrote an awsome thesis on collision detecion
and his seperate axis theorem.
pretty common sense, but i bet you didn't think of that /implement ;)
btw, i spelled goutshalks' name wrong, just do a search on google for obb and unc and it will pop his site up...
 
 

Most texts, when discussing floating point comparisons, stop immediately after discussing the problem with
floating point equality, assuming that other forms of comparison are perfectly okay with floating point numbers.
This isn't true!
If we are assuming that x=y if x is within y±error, then a simple bitwise comparison
of x and y will claim that x<y if y is greater than x but less than y+error. However, in such
a case x should really be treated as equal to y, not less than y. Therefore, we must always compare
two floating point numbers using ranges, regardless of the actual comparison we want to perform.
Trying to compare two floating point numbers directly can lead to an error. To compare two floating point numbers,
x and y, against one another, you should use one of the following forms:
 = if abs(x-y) <= error then ...
 <> (!=) if abs(x-y) > error then ...
 < if (x-y) < error then ...
 <= if (x-y) <= error then ...
 > if (x-y) > error then ...
 >= if (x-y) >= error then ...
You must exercise care when choosing the value for error. This should be a value slightly greater than
the largest amount of error which will creep into your computations. The exact value will depend upon
the particular floating point format you use, but more on that a little later.