Draw multiple views of scene on single screen <p>I have a class for projection in OpenGL, which a user can use as follows:</p> <pre><code>//inside the draw method customCam1.begin(); //draw various things here customCam1.end(); </code></pre> <p>The <code>begin</code> and <code>end</code> methods in my class are simple methods right now as follows:</p> <pre><code>void CustomCam::begin(){ saveGlobalMatrices(); glMatrixMode(GL_PROJECTION); glLoadIdentity(); glOrtho(-hParam,hParam,-tParam,tParam,near,far);//hParam and tParam are supplied by the user of the class glMatrixMode(GL_MODELVIEW); glLoadIdentity(); } void CustomCam::end(){ loadGlobalMatrices(); }; </code></pre> <p>I want the user to be able to create multiple instances of the above class (supply different params for <code>lParam</code> and <code>tParam</code> for each of these classes) and then draw all the three on the screen. In essence, this is like three different cameras for the scene which are two be drawn on the screen. (Consider for example top, right, bottom view to be draw on the screen with the screen divided in three columns).</p> <p>Now since there's only one projection matrix, how do I achieve three different custom cam views at the same time?</p>