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- From: bill@cambridge.apple.com (Bill St. Clair)
- Newsgroups: comp.lang.lisp.mcl
- Subject: Re: Whiter Whites?
- Message-ID: <9208311547.AA14193@cambridge.apple.com>
- Date: 31 Aug 92 16:51:50 GMT
- Sender: info-mcl-request@cambridge.apple.com
- Lines: 18
- Approved: comp.lang.lisp.mcl@Cambridge.Apple.C0M
- Full-Name: Bill St. Clair
- Original-To: korcuska@aristotle.ils.nwu.edu (Michael &)
- Original-Cc: info-mcl
-
- >Perhaps this has been discussed before. If so, sorry...
- >
- >I was using the following code (sort of) the other day to draw white text over
- >a colored background:
- >
- >(with-fore-color *white-color*
- > (with-cstrs ((s "A String"))
- > (#_TextBox s (length "A String") r #.#$teJustCenter))) ; where r is a Rect
- >
- >Much to my suprise the text is not white if the monitor is set to 4 bits deep
- >or less. Why? Well, from the AppleDoc for MCL:
-
- Guillaume Cartier reported this problem just last week. Oliver Steele
- suggested that scaling by 257 instead of 256 when mapping from 8 to
- 16 bit color components fixes the problem. I have a patch for MCL's
- MAKE-COLOR, COLOR-RED, COLOR-GREEN, & COLOR-BLUE functions that makes
- this change. It will be part of patch 2 for MCL 2.0 (patch 1 will be
- available soon). I'll send it to anyone who asks for "color-components-patch".
-