View Full Version : gluProject and gluUnproject source (for float data)

07-19-2005, 01:55 PM
Hi... does anyone have the source for GLU functions gluProject and gluUnProject???

I want to create float versions of them so I do not need to convert my matrices to double every frame. I made a float version of gluProject and it matches the results from the original double version. Here it is:

void gluProject_float(const vector3& p_obj, vector3& p_win)
vector4 t;
t = p_obj * view_matrix; // v3 * m(4x3)
t = t * proj_matrix; // v4 * m(4x4)
p_win.x = win_sizex * (t.x / t.w + 1.0f) * 0.5f;
p_win.y = win_sizey * (t.y / t.w + 1.0f) * 0.5f;
p_win.z = (t.z / t.w + 1.0f) * 0.5f;
}But can not find any info on how to implement gluUnProject. Any links for its definition or implementation in GLU???

I need this for a deferred shading demo ... works ok when converting to double before gluUnProject but think a float version would be nice as I do not use double anywere else.

07-19-2005, 02:24 PM
Your code for gluProject looks weird.
Shouldn't that be

vector4 t;
t = view_matrix * p_obj; // v3 * m(4x3)
t = proj_matrix * t; // v4 * m(4x4)I have a lib that is a a glu replacement

The functions you would be interested in

1. glhProjectd
2. glhProjectf
3. glhUnProjectd
4. glhUnProjectf
5. glhProjectf_2
6. glhProjectf_3
7. glhUnProjectf_2
8. glhUnProjectf_3
9. glhProjectf_SSE_Aligned_2
10. glhProjectf_SSE_Aligned_WarmCache_2
11. glhProjectf_SSE_Unaligned_2
12. glhUnProjectf_SSE_Aligned_2
13. glhUnProjectf_SSE_Aligned_WarmCache_2
14. glhUnProjectf_SSE_Unaligned_2

The 5 to 14 are for mass processing.

The source for the original GLU can be found in MESA (mesa3d.org)

07-19-2005, 03:19 PM
Go to http://www.mesa3d.org and get the latest source for the Mesa library, which includes its own version of libGLU, as well as SGI's implementation.

Look at:





07-19-2005, 03:48 PM
Thanks for the links and the quick reply.

V-man, the (matrix * vector) or (vertor * matrix) would be the same thing... anyway that was just a pseudo code not my actual code.

And thanks again for the library and source link.