Книга: DirectX 8 Programming Tutorial

Page Flipping

What is Page Flipping? Well, think of a flipbook. This is a number of pages with a slightly different drawing on each page. Then, when you hold the corner and flip the pages, it looks like the picture is moving. This is how DirectX Graphics works. You draw all of your objects onto a hidden page, known as the “Back Buffer”. Then when you have finished, flip it to the Front Buffer and repeat the process. As the user is looking at the new front buffer, your program will be drawing onto the back buffer.

What would happen without Page Flipping? Without Page Flipping, the user would see each object appear as it was drawn, which isn Їt what you want at all.

So, your game will basically consist of a loop, known as the Game Loop. Each time around the loop you process your game logic so you know where your objects will be. Next, you clear the Back Buffer. Then draw the current scene onto it. When this is done, flip it to the front and start the loop again. This will continue until the game is shut down. You may have a number of Back Buffers, this is known as a “Swap Chain”.

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