Good idea since there is so much implementations of "fixed-width
vectors/matrices" since the beginning of times. There has been
such efforts in the past to makes it more standardized.
There will be
On Friday, 11 October 2013 at 16:10:21 UTC, FreeSlave wrote:
Both templates should support all floating point types and
moreover user-defined (for example wrappers for GMP library and
others).
And integers for eg. video processing. Thankfully it's not that
much harder.
For efficiency in both cases matrices should use
one-dimensional array for inner representation. But actually
I'm not sure if matrices should support other container types
besides standard D arrays. The good thing about one-dimensional
arrays is that they can be easily exposed to foreign functions,
for example, to C libraries and OpenGL. So we should take care
about memory layout - at least row-major and column-major. I
think it can be templated too.
About 3D graphics: I don't think choosing one or the other is
that big a deal. I tend to prefer row major order but eg. gl3n
uses the reverse.
It's up to you. If you templated against order, you will be able
to implement you "asTransposed" idea.
Sometimes user takes data from some other source and wants to
avoid copying in Matrix construction, but she also wants to get
matrix functionality. So we should provide "arrayAsMatrix"
adapter, that can adopt one-dimensional and two-dimensional
arrays making them feel like matrices. It definitely should not
make copy of dynamic array, but I'm not sure about static.
Possible with pointer cast? (strict aliasing rule aside)
About operation overloading. It's quite clear about 'add' and
'subtruct' operations, but what's about product? Here I think
all 'op'-functions should be 'element by element' operations.
The product to me is a special case.
Element-wise matrix multiplication is seldom used, it's a lot
more common to want normal matrix multiplication. I and others
use "*" for that purpose.
https://github.com/Dav1dde/gl3n/blob/master/gl3n/linalg.d#L1734
https://github.com/p0nce/gfm/blob/master/gfm/math/matrix.d#L150
https://github.com/gecko0307/dlib/blob/master/dlib/math/matrix.d#L171
So we can use all other operations too without ambiguity. For
actual matrix multiplication it can provide 'multiply' or
'product' function. It's similar to Maxima approach, besides
Maxima uses dot notation for these needs.
But it's dissimilar to shader languages and existing D libraries.
Invertible matrix. It must not be allowed for square
StaticMatrix. DynamicMatrix may make checks at runtime. Same as
for transposition we can implement 'invert' to invert in place
and 'inverted' to make copy. There is issue here - what should
we do when determinant is 0?
Use enforce to crash. Dividing by zero is not recoverable.
