Features of GDI-Sub

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Features of GDI-Sub

    * In designing GDI-Sub, portability with GDI/DirectDraw is well-considered at the application level. GDI-Sub is equipped with timing controls, command lists, and other extensions needed for automotive requirements, and its architecture is designed to follow GDI/DirectDraw as much as possible for major principles such as drawing APIs and surface management. On the other hand, from the perspective of system development, the GDI-Sub framework does not depend on the GDI/DirectDraw modules. GDI-Sub does not require the GDI/DirectDraw modules unless compatible applications which use GDI are used; thus it is possible to construct simple systems. In addition, the GDI-Sub system has a device prepared to use GDI applications in the conventional manner.

    * A graphic accelerator in the form of a command list used on automotive systems can directly interrupt and execute commands, making the best use of the intrinsic performance of the hardware. A command generation mechanism is realized in the client library, thus issuing a mass drawing command can be handled at high speed without context-switching in client applications. This enables the drawing portion of the application entity to make a quicker response and makes convenient real-time design possible.

    * On GDI-Sub, the end of asynchronous execution of a series of command lists and the subsequent display switching can be handled as a transaction. With the transaction, applications can asynchronously handle the sequence from the queuing for command execution to the display switching subsequent to the end of execution. In transactions, you can specify parameters such as display switching time (frame interval), display switching of surfaces, command execution priorities, and transaction cancellation. The GDI-Sub Server module handles drawing completion interrupts from the hardware and VSYNC interrupts at the ISR level as far as possible to efficiently handle successive execution and synchronous processing.

    * As the display resolution is becoming higher due to increased hardware quality, it has become difficult to retain multiple sizes of fonts in bitmap on Asian systems using many character sets. GDI-Sub has a function to provide applications with bitmap images that the GDI-Sub drawing API can draw, referring to Windows-compatible TrueType outline fonts and bitmap fonts included in AUI skins.

    * On a system without a graphics accelerator, command lists are interrupted by a thread of a priority different from the application (software rendering) to perform the drawing process. This enables a system with a graphics accelerator and a system without a graphics accelerator to take the same command list model, thus making systems more scalable to ensure application portability.

    * GDI-Sub applications can be checked for their drawing operations on a PC with the GDI-Sub PC emulator. The PC emulator handles command execution on software, superimposing multiple surfaces, and other processing to allow checking the operation of a GDI-Sub application in an environment close to the real machine.

Source : MSDN