libmath itself doesn't expose any stream operators anymore. However,
libutils is able to automatically print libmath types into its
io::ostream -- however matrices are not formatted nicely.
Added a new optional library, libmathio, that provides std::ostream
operators for all libmath types. libmathio does a better job at
formating matrices.
Also removed apply() and map() from libmath because there were not used
anywhere and they forced us to depend on <functional> in public headers.
This is a similar fix to the previous vector fix. Commutative
operations now always return the same type and the operations are
carried out in the precision resulting from following traditional
C++ rules.
This is nicer because this way the methods that don't match don't
even exist. Also make it better when editing code with a C++ aware
ide.
Also use the less verbose std::enable_if_t<>
It turns out that most of libmath couldn't be used in constexpr
expression due to our use of union{}. The C++ standard requires that
all accesses to a union{} in a constexpr expression be the same
element.
Also because libm and cmath are not constexpr some functions such
as length() or normalize() can't be constexpr. The same is true for
anything needing things like sqrt, cos, sin, ceil, floor.
This change mainly does the following:
- replace all accesses to vector elements by operator[]
(this ensure all of libmath uses the same union element)
- avoid use of std::min / std::max / std::abs
- avoid uninitialized variables, which can't be constexpr
- remove 'constexpr' keyword on functions that can never be
It is now possible to write things like:
constexpr mat4f I = inverse(
transpose(mat4f::translation(float3{ 1, 2, 3 })
* mat4f::scaling(4)));
These two functions expect a vector of the same size as the
matrix's storage vectors (float4 for a mat4f for instance) which
has two major issues:
- The vector must end with 1 for homogeneous coordinates to work
- Passing a single scalar (mat4f::scale(0.5)) creates a matrix
whose diagonal is set to that scalar, thus breaking homogeneous
coordinates
With this change scale and translate expect a vector who dimensionality
is 1 less that of the matrix's underlying storage vectors. i.e. a float3
for mat4f.
