1. Introduction to C & C++ Lecture 13 – libQGLViewer JJCAO

2. libQGLViewer • C++ library • based on Qt • eases the creation of OpenGL 3D viewers with some of the typical 3D viewer functionalities: • move the camera using the mouse • object selection • camera paths control using F1..F12 (demo with simpleViewer) • screenshot saving • …

3. Without libQGLViewer void MyGLWindow::draw(){ if (!valid())//for window creat and resize initGL(); // clears the color buffer and depth buffer using the current clearing color glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); view_all();// setup camera (only once) //begin of drawing glPushMatrix();//to avoid cumulate effect //setup viewpoint from current arcball arcball_.glDraw(); // draw … … glPopMatrix(); //end of drawing }

4. Demos • CGAL-3.8\demo\Triangulation_3

5. simpleViewer D:\libQGLViewer-2.3.10\examples\simpleViewer

6. manipulatedFrame D:\libQGLViewer-2.3.10\examples\manipulatedFrame

7. manipulatedFrame setManipulatedFrame(new ManipulatedFrame()) glMultMatrixd(manipulatedFrame()->matrix()); setAxisIsDrawn() drawAxis() D:\libQGLViewer-2.3.10\examples\manipulatedFrame

8. Select /pick D:\libQGLViewer-2.3.10\examples\select

9. Select /pick D:\libQGLViewer-2.3.10\examples\select

10. Select /pick virtual void drawWithNames(); virtual void postSelection(constQPoint& point); glPushName(i); camera()->convertClickToLine(point, orig, dir); selectedPoint = camera()->pointUnderPixel(point, found); selectedName(); D:\libQGLViewer-2.3.10\examples\select

11. keyboardAndMouse D:\libQGLViewer-2.3.10\examples\keyboardAndMouse

12. keyboardAndMouse No effect! Why? D:\libQGLViewer-2.3.10\examples\keyboardAndMouse

13. keyboardAndMouse D:\libQGLViewer-2.3.10\examples\keyboardAndMouse

14. keyboardAndMouse D:\libQGLViewer-2.3.10\examples\keyboardAndMouse

15. keyboardAndMouse • setShortcut()changestandard action bindings (axis, grid or fps display, exit...). • setMouseBinding() and setWheelBinding()changestandard action mouse bindings (camera rotation, translation, object selection...). • If you want to define new keyboard shortcuts, overloadkeyPressEvent() and bind your own new actions. Use setKeyDescription() to add your shortcuts in the help window. • To define new mouse actions, overload mouse(Press|Move|Release)Event. OverloadsetMouseBindingDescription() to update the help window binding tab. D:\libQGLViewer-2.3.10\examples\keyboardAndMouse

16. Animation D:\libQGLViewer-2.3.10\examples\animation

17. Animation D:\libQGLViewer-2.3.10\examples\animation

18. Animation • When animation is activated(the Returnkey toggles animation), the animate() and then the draw() functions are called in an infinite loop. • You can tune the frequency of your animation (default is 25Hz) using setAnimationInterval(). The frame rate will then be fixed, provided that your animation loop function is fast enough. D:\libQGLViewer-2.3.10\examples\animation

19. Interface Practice in the Designer D:\libQGLViewer-2.3.10\examples\interface

20. More examples