Have a look at : WinEraseChars Purpose
Erase the specified characters in the draw window. Prototype void WinEraseChars (const Char *chars, Int16 len, Coord x, Coord y) Parameters -> chars Pointer to the characters to erase. -> len Length in bytes of the characters to erase. -> x x coordinate of the first character to erase (left bound). -> y y coordinate of the first character to erase (top bound). Result Returns nothing. Comments The winMask transfer mode is used to erase the characters. See WinDrawOperation for more information. This has the effect of erasing only the on bits for the characters rather than the entire text rectangle. This function only works if the foreground color is black and the background color is white. See Also WinDrawChar, WinDrawChars, WinDrawInvertedChars, WinDrawTruncChars, WinInvertChars, WinPaintChar, WinPaintChars Vincent -----Message d'origine----- De : Daniel Seifert [mailto:[EMAIL PROTECTED]] Envoy� : mardi 3 septembre 2002 15:31 � : Palm Developer Forum Objet : Re: Way to shut off background erase when using WinDrawChars? Am Die, 2002-09-03 um 14.16 schrieb Richard Coutts: Hi, > I tried using WinPaintChars and got the same results (the off bits were > drawn using the bacground color, instead of not being drawn at all). You didn't change the drawing mode. > sounds like I need to learn what is meant by the "current drawing state > transfer mode." You can find this in the API reference manual: ---------------------------------------------------------------------- Purpose: Set the transfer mode to use in subsequent draw operations. Prototype: WinDrawOperation WinSetDrawMode (WinDrawOperation newMode) Parameters -> newMode Transfer mode to set; specify one of the WinDrawOperation values. Result: Returns the previous transfer mode. Comments: This function changes the current drawing state. If necessary, use WinPushDrawState to preserve the current drawing state before you set this function and use WinPopDrawState to restore it later. Compatibility: Implemented only if 3.5 New Feature Set is present. ---------------------------------------------------------------------- So you might do something like WinPushDrawState(); WinSetDrawMode(winOverlay); WinPaintChars(...); WinPopDrawSate(); HTH, Daniel Seifert -- For information on using the Palm Developer Forums, or to unsubscribe, please see http://www.palmos.com/dev/support/forums/ -- For information on using the Palm Developer Forums, or to unsubscribe, please see http://www.palmos.com/dev/support/forums/
