DirectX Graphics Common Errors (Selected)
Richard Huddy, NVIDIA CORP.
Translation of Nightmare (QinGru Li)
** They should appear in the initialization section
Be careful not to make time-consuming expensive API calls in efficiency sensitive part
- ValidateDevice ()
- cretevb ()
- Destroyvb ()
- Optimize ()
- CreateStateBlock ()
- AssemblevertexShader ()
** template buffer, when you don't need ...
- If you only clear the Z buffer, the system has to retain the template buffer
So if you use the template buffer, clear the Z buffer time together
- This means that if you have different clashes, Clear () will slow
Read and write every pixel
- Do not use painting rectangles to clear buffer
** Remove redundant state changes, who is responsible?
- Driver has to do this on Pure Hal
Such drivers should be quite radical
- Renar in non-Pure Hal works this
But only remove simple repeat
- Your program is the best place
** Excessive change Vertex Shader or Pixel Shader
- will force the system to refresh the state
- This is actually expensive, even more expensive than material changes
- So make sure you have not repeatedly set the same shader
** DrawPrimitiveup
- want me how many times, use VertexBuffer
(Translator Note: DrawPrimitiveup will lead to additional data replication, but simple programs can make the program simply, trade-off.)
** Use GDI to draw word
- will block the operation of the CPU until the completed rendering
- Words should be drawn using 3D function, like D3DX
- If your text is not dynamic
Use a texture containing text
** Use n-patches
- I don't recommend this
- just NVIDIA's opinions
But we insist on this position
This technology has too many details
We think it is just the appealing on the surface.
** Use W-buffer instead of Z-Buffer?
- Perspective projection material will not work (on GeForce 1, 2)
- And you will not be able to close the perspective correction
- Cubemap will fail (in Geforce 1, 2)
- If you are using VertexShader, you still have to set the projection matrix
** Color Key
- Test using Alpha because it is better
Color Key does not exist in DX8
- There is no pair, because for multiple materials and double linear filtration colorKey is a metamorphosis
** No object
- usually leads to the next time to create a broken device object
- Use the test library
- Remember to release the selected material before clearing
