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kag101
07-07-2004, 07:48 AM
Does anyone know how to display the x,y,& z axes in open GL?

jabe
07-07-2004, 08:32 AM
you can draw three lines representing the different axis in different colors.

example:

glMatrixMode(GL_MODELVIEW);
glPushMatrix();
glTranslatef(axisCenterPointX, axisCenterPointY, axisCenterPointZ);

// x axis
glColor3f(1,0,0);
glBegin(GL_LINES);
glVertex3f(0,0,0);
glVertex3f(axisLength,0,0);
glEnd();

// y axis
glColor3f(0,1,0);
glBegin(GL_LINES);
glVertex3f(0,0,0);
glVertex3f(0,axisLength,0);
glEnd();

// z axis
glColor3f(0,0,1);
glBegin(GL_LINES);
glVertex3f(0,0,0);
glVertex3f(0,0,axisLength);
glEnd();

glPopMatrix();

instead of using the modelview matrix you can add a centerpoint inside the glVertex commands.

jan