: I have several text fields that are updated on screen a couple of times : a second. I find that the freetype font FreeSans.ttf doesn't paint the : background except just a few pixels surrounding each character. This : leaves artifacts of previous messages on the screen.
By default, most text drawing is done drawing the foreground bits only, using anti-aliasing if specified, blending the edges of the characters with the existing background. To turn on background pixel drawing using the current background color, use GrSetGCUseBackground(gc, TRUE); I have been working extensively with some issues in the recent git repository. The issues have to do with drawing rotated character strings and some driver bugs. I've recently updated the drivers to make sure they always draw the background bits when requested. However, there are still issues, as the freetype driver only draws character glyphs (foreground and background) in a minimal bounding box for the character, not the entire large string rectangle. Jim, go ahead and try setting the above background drawing request. If there are still issues, I have some code that will work, that I've not checked in (I'm in the middle of a large update to all font subdrivers, where all use very fast blit routines to output text, instead of pixel by pixel as in the case with some font subdrivers). I have decided to wait until after 0.92 ships before integrating the new design. : : My questions are can I force GrText to paint the background solid? Do I : have to use GrFillRect() before painting the text? The fixes I have talked about above use fillrect to fill the entire area before drawing, so it shouldn't be necessary to do it on your own. The font subdriver also knows exactly where to paint this rectangle. : Do other fonts do this differently? Each font subdriver (freetype2, freetype1, pcf, fnt and t1lib) do this differently in the current code. Also, the output routines differ depending on whether anti-aliasing is specified. (antialiasing is only supported in freetype and t1lib/type1 fonts). : Is there a better way? No, using GrSetGCUseBackground is the preferred approach. Let me know how it works. Regards, Greg --------------------------------------------------------------------- To unsubscribe, e-mail: nanogui-unsubscr...@linuxhacker.org For additional commands, e-mail: nanogui-h...@linuxhacker.org
