Hi, Im working on little 3d editor in opengl. I have problem with object selection in opengl. When i use single wievport (same size as my application window) everything is allrigh, and selection is working well. But when i try to modify glViewport size selection dies. :( Check this : -------------------- In Main() glViewport (0, 0, Form1->Width, Form1->Height); glOrtho( 0.0, Form1->Width, 0.0, Form1->Height,-0.5,2.5 ) In ProcessSelect() glGetIntegerv(GL_VIEWPORT, viewport); glOrtho( 0.0, Form1->Width, 0.0, Form1->Height,-0.5,2.5 ); ------------------- This works great. -------------------- In Main() glViewport (0, 0, Form1->Width/2, Form1->Height/2); glOrtho( 0.0, Form1->Width/2, 0.0, Form1->Height/2,-0.5,2.5 ) In ProcessSelect() glGetIntegerv(GL_VIEWPORT, viewport); glOrtho( 0.0, Form1->Width/2, 0.0, Form1->Height/2,-0.5,2.5 ); ------------------- This one is not working at all :( How to fix it? how to use opengl selection in multiple viewports? Whats im do wrong? Thanks for help! /lar