openglselectionstack-overflowpickingstackunderflow

glPushName + glPopName stack overflow and underflow


Can anybody explain me how to use glPushName and glPopName. I like to use them instead of glLoadName, but I laways get GL_STACK_OVERFLOW and GL_STACK_UNDERFLOW errors. (First, under then overflow).

Example code would help me too.

Note #1: My Rendering/selection_rednering code consists of multiple glBegin(...)/glEnd() blocks, if this is any problem plus various Rotations and Transformations.

Note #2: I know that GL selection / picking is deprecated, but I have to implement it within a Application which was developed a with OpenGL2.1 a while ago.


Solution

  • In this case I was just dumb, because that stackoverflow was caused by doing to much glPushMatrix, as that stack has a very low capacity (3 in my special hardware case). Drawing mode worked just fine, but I have an additional Matrix used for picking mode.

    How to use glPopName /glPushName(name)

    glPushName(obj->name());
    glBegin(...);
    //draw it;
    glEnd();
    
    glPushName(obj->child->name());
    glBegin(...);
    //draw child it;
    glEnd();
    
    glPopName();
    glPopName(); //important, or yoou will get a stackoverflow after some time