OpenInventor: OpenGL calls invisible when far from IV objects


I have another small problem-question(I think its the last one) about including OpenGL calls with OpenInventor technology. I noticed this a long ago that when drawing OpenGL call in an SoPerspectiveCamera scene, the vertex which are far from the OpenInventor camera aren’t shown on the screen. This problem does not exist for the Ortho view. The problem seems to be with a Near and Far value limits.

A video with the problem is available here at:

In the video you can see that when you add the grid(which is all OpenInventor objects), the lines(in OpenGL) are shown correctly in the 3d view. When you dont, the camera cut the lines. There is no problem for the Ortho X,Y,Z views. I include the code below for the OpenGL white lines in the video.

Do you know why OpenInventor with SoPerspectiveCamera doesn’t render all the OpenGL scene all the time without needing OpenInventor objects at each limits?

Thank you for your help,
Louis-Charles Dumais

Here is the code:

float tempLength= 5.0f;
 	glVertex3f( -tempLength,0.0f, 0.0f);glVertex3f(tempLength,0.0f, 0.0f);
	glVertex3f( 0.0f,-tempLength, 0.0f);glVertex3f(0.0f,tempLength, 0.0f);	
	glVertex3f( 0.0f,0.0f, -tempLength);glVertex3f(0.0f,0.0f, tempLength);	


Please post questions like these in the “high-level toolkits” forum.

– Tom