Direct2D

Experiments with Microsoft Direct2D API.

Things to know about DirectX:

• Resizing the window requires that everything be released and re-created. This includes all dependent offscreen bitmaps (sprites). This is why most games run in full-screen mode.
• RenderTargets may reference GPU memory, which the CPU cannot access.
• No draw operations are executed until EndDraw(). This is why the Tags are so important.
• VMware emulates a basic GPU in software. DirectX performance in a VM will be much slower than running natively.

The Rocket project has been a great way to learn about Direct2D and to evaluate the performance of a modern graphics system. I have learned many things, some of which were a surprise. If I were to start Rocket from scratch today:

• All item information would be stored as FLOAT.
• All motion information would use polar vectors, direction and velocity.
• All angles would be in radians.
• I would use Direct2D and the paint method.