The UpdateColors function updates the client area of the specified device context by remapping the current colors in the client area to the currently realized logical palette.
BOOL UpdateColors(
| HDC hdc | // handle of device context |
| ); |
Parameters
hdc
Identifies the device context.
Return Values
If the function succeeds, the return value is nonzero.
If the function fails, the return value is zero. To get extended error information, call GetLastError.
Remarks
An application can determine whether a device supports palette operations by calling the GetDeviceCaps function and specifying the RASTERCAPS constant.
An inactive window with a realized logical palette may call UpdateColors as an alternative to redrawing its client area when the system palette changes.
The UpdateColors function typically updates a client area faster than redrawing the area. However, because UpdateColors performs the color translation based on the color of each pixel before the system palette changed, each call to this function results in the loss of some color accuracy.
This function must be called soon after a WM_PALETTECHANGED message is received.
See Also