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In computer science and visualization, a canvas is a container that holds various drawing elements (lines, shapes, text, frames containing other elements, etc.). It takes its name from the canvas used in visual arts. It is sometimes called a scene graph because it arranges the logical representation of a user interface or graphical scene. Some implementations also define the spatial representation and allow the user to interact with the elements via a graphical user interface. See (this article ) for an overview (2010-08-15) of a small handful of canvas implementations. ==Library support== Various free and open-source canvas or scene graph libraries are available for developers to use to create a user interface and/ or user interface elements for their computer programs. Example free and open-source scene-graph canvas options include: * In C, (Evas ) from the Enlightenment project. * In C, Clutter associated with the GNOME project. * In C, GTK+ Scene Graph Kit (GSK) * In C, Pigment * In C++ or optionally their own markup QML, Qt Quick, provides a (scenegraph ) associated with the Qt project. * In C++, OpenSceneGraph, a 3D graphics API using OpenGL. * In C++, the OGRE scene graph based engine supports multiple scene managers. * In C++, OpenSG, a scene graph system for real-time graphics, with clustering support and multi-thread safety. * In C++, the FlightGear Flight Simulator uses a custom Canvas system (LGPL'ed via SimGear〔gitorious.org/fg/simgear〕) that is hardware-accelerated using OpenSceneGraph/OpenGL, OpenVG/ShivaVG:〔http://wiki.flightgear.org/Canvas_Development〕 (The FlightGear Canvas system ) * In Java, the Java FX scene graph with 2D and 3D functionality. There are canvas modules within various libraries which do not provide the power of a full scene-graph. That is, they operate at a lower level which requires the programmer to provide code such as mapping mouse-clicks to objects in the canvas. Examples libraries which include such a canvas module include: * In C++, KDE Plasma Workspaces (Corona ) canvas * The Canvas element in HTML5 * For Java, the AWT library (Canvas ) * For Java, the Java FX library (Canvas ) * For Java, the Swing library (Canvas ) * For Java, the SWT library (Canvas ), associated with Eclipse * For Java-like JavaScript, the GWT library (Canvas ) * For Tcl/Tk, the (canvas ) widget * For Python, the Tkinter library (canvas ) * In C++, the (papyrus Canvas library ) which renders using the Cairo (graphics) library * In C, (crcanvas ), a GTK+ canvas widget which renders using the Cairo (graphics) library * In C, (GooCanvas ), a GTK+ canvas widget which renders using the Cairo (graphics) library There are proprietary canvas libraries as well, for example: * The Microsoft Windows Win32 (Canvas ) 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Canvas (GUI)」の詳細全文を読む スポンサード リンク
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