_RED
Jump to navigation
Jump to search
Navigation:
Main Page with Articles and Tutorials
Keyword Reference - Alphabetical
Keyword Reference - By usage
Report a broken link
The _RED function returns the palette index or the red component intensity of a 32-bit image color.
Syntax
- redIntensity& = _RED(rgbaColorIndex&[, imageHandle&])
Description
- rgbaColorIndex& is the RGBA color value or palette index of the color to retrieve the red component intensity from.
- The LONG intensity value returned ranges from 0 (no intensity, not present) to 255 (full intensity).
- imageHandle& is optional.
- If imageHandle& specifies a 32-bit color image, rgbaColorIndex& is interpreted as a 32-bit RGBA color value.
- If imageHandle& specifies an image that uses a palette, rgbaColorIndex& is interpreted as a palette index.
- If imageHandle& is not specified, it is assumed to be the current write page.
- If imageHandle& is an invalid handle, an invalid handle error occurs.
- If rgbaColorIndex& is outside the range of valid indexes for a given image mode, an illegal function call error occurs.
- Uses index parameters passed by the _RGB, _RGBA, _RGB32 or _RGBA32 functions.
Examples
- See the example in POINT.
See also