2D rendering

OpenGL OpenGL: Advanced Coding
1

Is there a way to use opengl to do 2D rendering without perspective,
I want to use this for top, side and front views
of wireframe objects

2

hi,

i believe you can use the gluOrtho2D function with the projection matrix to achieve this

   
glMatrixMode(GL_PROJECTION);
glPushMatrix();
glLoadIdentity();
gluOrtho2D(0.0, 1.0, 0.0, 1.0);

then use the modelview matrix with glRasterPos function.

  
glMatrixMode(GL_MODELVIEW);
glPushMatrix();
glLoadIdentity();
glRasterPos3f(0, 0, 0.0);

…

for more details OpenGL Red Book: Chapter 3 - Veiwing

hope this helps

3

Also, if you still want to draw polygons, etc., you can use glVertex2f(). (glRasterPos() is good if you’re drawing pixels).