ADL support

[Jaxan]

We moved from our own math library to glm and noticed some difference. For example we had something like this in our codebase:

using vec3 = ourlib::vec3;

vec3 a(1,0,0);
auto b = normalize(a);

Note that this works as long as normalize is defined in the same namespace as the vectortype (this is how ADL works). I was hoping that we could change to glm by just changing the typedefs. However in this case normalize could not be found, as normalize is not in the namespace glm::detail.

In order to let this work I made this header (as an extension of course), which injects all glsl functions in the glm::detail namespace.

Pros:

• Switching between math libraries is easier.
• Still better than using namespace glm;.

Cons:

• Different functions might be called depending on which headers are included.

Fun fact: there is a one-line trick to inject the detail namespace into the glm namespace: http://ideone.com/ZqUiHX (the hack is on line 20). But this is just weird ;).

Any thoughts?

[NickNick]

For what it's worth, I'd rather see this in the specific headers that are included now in this one header, so that ADL is always functioning after including trigonometric.hpp, exponential.hpp, etc. instead of also having to include this one header.

[Groovounet]

I resolved this issue a little differently by moving tvec* and tmat* types to glm namespace.

I think this should resolve your issue.

Thanks,
Christophe

[Jaxan]

That should also resolve the issue indeed. The reason I implemented it like this was that I didn't want to change glm, but just add behaviour in our codebase (so that we could stick to glm 0.9.5.4 in brew).

Thanks!