Translate function not working??

[nasser225]

I have this from a tutorial:

vec = glm.vec4(1.0,0.0,0.0,1.0)
id_matrix = glm.mat4()
trans_matrix = glm.translate(id_matrix, glm.vec4(1.0, 1.0, 0.0))
vec = trans_matrix * vec

printing vec gives 0.0,0.0,0.0 and I was expecting 2.0,1.0,0.0

Please help! Thanks

[Zuzu-Typ]

Hi nasser225,
you are indeed correct - the translate() function was not working as intended, however that is actually not the reason why the code above is not functional.
In gtruc/glm (the original glm) there has been a change to the way matrices are initialized (or rather - they removed the initialization completely) g-truc/glm@4cf8a10 .
This results into glm.mat4() returning an uninitialized (empty) matrix:

[0, 0, 0, 0]
[0, 0, 0, 0]
[0, 0, 0, 0]
[0, 0, 0, 0]

That's why the translation doesn't work.
You have to use glm.mat4(1.0) instead.

I'm trying to get gtruc to revert this change (because I ran into the same problem as you did).

[dwtd]

I also noticed that translate (and scale) don't seem to be working, but unrelated to the matrix initialization issue you mentioned from the original GLM. As a simple example:

    M = glm.translate(glm.mat4(1.0), glm.vec3(2.0, 2.0, 2.0))
    print("M:\n{}".format(M))

produces:

M:
[            1 |            0 |            0 |            0 ]
[            0 |            1 |            0 |            0 ]
[            0 |            0 |            1 |            0 ]
[            0 |            0 |            0 |            1 ]

If I change translate to scale I get:

M:
[            0 |            0 |            0 |            0 ]
[            0 |            0 |            0 |            0 ]
[            0 |            0 |            0 |            0 ]
[            0 |            0 |            0 |            1 ]

Something here is clearly not right. For a sanity check, I confirmed that in C++ the translate and scale functions do the right thing, and they do.

[Zuzu-Typ]

I accidentally screwed up the macro that generates the two of these functions, resulting in them always using empty arguments.
I'll release a fix soon