Re: [boost] Is there any interest in a geometry library?

From: Michael Marcin (mmarcin_at_[hidden])
Date: 2007-03-06 15:07:38

Jeremy Pack wrote:
> If it is geared towards 3D development, it probably ought to provide
> conversions to and from the various constructs used for 3D
> transformations (things like rotation matrices, Euler angles etc.).
> Without that, I think it will just be duplicating functionality
> already in Boost, just with a different API.
>
> How hard would it be to make the Boost Quaternion classes work with
> the Matrix classes in Ublas?
>

Even the Ublas documents recommend not using it for small fixed sized 
vectors and matrices.
It recommends tvmet.

What I need is a library with:

all types parameterized on a value_type
all or most operations optionally customizeable for efficiency or precision 
concerns
conversion between types with different value_types
2, 3 and 4 component vector and point classes
2x2, 3x3, 3x4, 4x4 matrix classes
an euler paramaters class (normalized quaternions)
euler angles with clear semantics (preferably definable discussed in P.S. 
below)
degrees and radians classes (i also need to define another similar type 
myself and use it with the rest of the system)
trig functions to work with the degrees and radians types
cross and dot products for 3 component vectors
conversions between euler angles, euler parameters, and matrix 
representations
transformation concatenation
vector transformations
an optimized implementation using all the tricks of Boost.Fusion and generic 
programming in general
a drop-in replacement unoptimized naive implementation to ease debugging and 
give a fallback for non-conforming compilers
a Boost compatible license

This is just off the top of my head but I think it's enough to show that 
many libraries cover some of my needs but no existing library I have found 
can cover all of them.

P.S.
Euler angles are the bain of my existence when writing math libraries and 
reading reference material or other people's code.
The semantics or almost never clearly defined enough.  If possible I'd like 
any euler angles tuple to have the following configurable with details 
documented.

First [yaw | pitch | roll] is applied as a [counter-clockwise | clockwise] 
rotation around the [positive | negative] [x | y | z] axis.
Then [yaw | pitch | roll] is applied as a [counter-clockwise | clockwise] 
rotation around the [positive | negative] [x | y | z] axis.
Finally [yaw | pitch | roll] is applied as a [counter-clockwise | clockwise] 
rotation around the [positive | negative] [x | y | z] axis.

- Michael Marcin