[cairo] text on win32
vladimir at pobox.com
Tue Feb 13 16:27:40 PST 2007
----- "Behdad Esfahbod" <behdad at behdad.org> wrote:
> On Mon, 2007-02-12 at 19:43 -0500, Daniel Amelang wrote:
> > So some quick fix needs to be applied so that 1.4 doesn't ship with
> > broken win32 font code. Does Jordan's patch solve the problem well
> > enough for now? Should we just define WIN32_FONT_LOGICAL_SCALE to 1
> > like in the mozilla code?
> Owen already commented on why we use a larger LOGICAL_SCALE. From what
> I understood, that is necessary for subpixel positioning of rotated text.
Yes, because IIRC, the idea is to render the glyph N times bigger than it needs to be, then scale it down to get correct subpixel behaviour. However, the problem with LOGICAL_SCALE is that it's applying a very big hammer to a small (and infrequently hit, compared to the common case) problem. I believe it should only be used to generate glyph images, and those images should then have a scale set in their surface device transform matrix. (I don't think that functionality existed when the code was originally written.)
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