Contents User Forum Source Index APIs by Task APIs by Level Data Application Framework Debugging Using OpenGL with G3D Introduction G3D::GApp is an application-starter class. To easily create a G3D application, make a subclass of G3D::GApp, which handles any state shared between all pieces of your program. A G3D::GApplet is a usable but not standalone component of your application. Each GApplet corresponds to a different major UI state. For example, the main menu of a game is one GApplet, and the actual game screen is another. If you have a big, modal in-game menu, that can be another GApplet. (A GApplet is not like a Java applet. A Java applet is a little application, but complete, and standalone, while a GApplet is neither complete nor standalone.) You may create one or more GApplet subclasses and instantiate them at the beginning of the program. Typically, they will be stored in your GApp subclass. You do not need to use GApplet's, however; you can just use GApp, if your application isn't too complex. You write code that calls G3D::GApplet::run on the current GApplet. That applet releases control by setting GApplet::endApplet = true. Your master loop (implemented inside the G3D::GApp::main) then chooses the next GApplet to run and invokes run() on it. If anything sets G3D::GApp::endProgram to true, the entire program should quit. GApp and GAppSettings GApp contains a lot of functionality that might make your life easier or better! In particular, look at G3D::GWindowSettings for lots of rendering controls. G3D::GApp's construct takes an optional G3D::GAppSettings argument, whose window attribute is an instance of G3D::GWindowSettings. To turn on full-screen anti-aliasing, use G3D::GWindowSettings.fsaaSamples. Full screen mode can be set using G3D::GWindowSettings.fullScreen, just set this value to true. Also, the initial position of the window can be moved using G3D::GWindowSettings.x and G3D::GWindowSettings.y. An alternative method of performing this is to set the G3D::GWindowSettings.center, if this is set to true, the window will appear in the center of the screen. It is even possible to use stereo hardware with G3D, using G3D::GWindowSettings.stereo. Using G3D::GApp::debugController, it is possible to get 'FPS style' controls (W,A,S,D and mouse look) at the start of the development, this then be replaced when development is at a stage to support it. See the main.cpp in demos for an example of this in use and how to activate it. Applets G3D::GApp, G3D::GApplet, G3D::GAppSettings, G3D::GWindowSettings Or Not! The G3D::GApp classes are provisional: the interface is likely to change. You don't have to use them; it is fine to instantiate G3D::RenderDevice and the other classes yourself. See demos/main-no-GApp.cpp for an example of how to not use GApp. Models Selection When G3D::UserInput::keyPressed(GKey::LEFT_MOUSE) is true, the user has clicked the mouse. You can convert the G3d::UserInput::mouseXY position to a 3D G3D::Ray with G3D::GCamera::worldRay and use G3D::Ray::intersects or G3D::CollisionDetection methods to see if that ray hits the G3D::PosedModel::getBounds region or a primitive like G3D::Capsule. User Interface Consider using a GUI library (GLUT, FLTK, wxWindows, qtWindows, .NET) to make your UI. FPS controls via G3D::ManualCameraController. The GApp creates one for you and if you call G3D::GApp::setDebugMode(true) you can press TAB to use it. key strokes, mouse, and joystick through G3D::UserInput G3D::RenderDevice::push2D to switch to 2D rendering mode (don't forget to call G3D::RenderDevice::pop2D at the end). This mode lets you draw text with G3D::GFont and render UI elements. G3D::Rect2D::contains detects whether the mouse is within a 2D region. Hosted by