|
Size: 960
Comment: Update TextureID > Texture*
|
Size: 1304
Comment: update content (w/ Sam); remove 'draft' note
|
| Deletions are marked like this. | Additions are marked like this. |
| Line 3: | Line 3: |
| ||<tablewidth="100%"style="color: rgb(255, 0, 0); text-align: center;">DRAFT|| | |
| Line 6: | Line 5: |
| Use this function to set an additional alpha value used in render copy operations. | Use this function to set an additional alpha value multiplied into render copy operations. |
| Line 21: | Line 20: |
| Returns 0 on success or -1 if the texture is not valid or alpha modulation is not supported; call [[SDL_GetError]]() for more information. | Returns 0 on success or a negative error code on failure; call [[SDL_GetError]]() for more information. |
| Line 29: | Line 28: |
| ''You can add useful comments here'' | Alpha modulation is not always supported by the driver; it will return -1 if alpha modulation is unsupported. When a texture is copied, during the copy operation the source alpha value is modulated by this alpha value according to the following formula: `srcA = srcA * alpha` The [[SDL_RendererInfo]] for the current renderer has a mask of supported channel modulations which will have SDL_TEXTUREMODULATE_ALPHA set if alpha modulation is supported. |
| Line 33: | Line 37: |
| .[[SDL_SetTextureColorMod]] |
SDL_SetTextureAlphaMod
Use this function to set an additional alpha value multiplied into render copy operations.
Contents
Syntax
int SDL_SetTextureAlphaMod(SDL_Texture* texture,
Uint8 alpha)
Function Parameters
texture |
the texture to update |
alpha |
the source alpha value multiplied into copy operations |
Return Value
Returns 0 on success or a negative error code on failure; call SDL_GetError() for more information.
Code Examples
You can add your code example here
Remarks
Alpha modulation is not always supported by the driver; it will return -1 if alpha modulation is unsupported.
When a texture is copied, during the copy operation the source alpha value is modulated by this alpha value according to the following formula:
srcA = srcA * alpha
The SDL_RendererInfo for the current renderer has a mask of supported channel modulations which will have SDL_TEXTUREMODULATE_ALPHA set if alpha modulation is supported.
