well, i was learning how to use picking (select an object in opengl with the mouse) and i came across a error. the Y offset is not right, it's about 1 inch below where it should be when clicking the mouse. Then i searched for the same problem in the whole site and found this guy experiencing the same problem i was , and his code seems pretty the same. Please someone help me! i'm 3 night working on this issue.

The only way i found is decreasing 30 pixels in the mouse_y var. thus the picking works fine, but doesn't seem reliable.