[TYPO3-core] RFC: Bugfix #7452: GIFBUILDER: wrong bounding box calculation with TEXT and spacing

[Oliver Hader]

Hi Ralf,

Ralf Hettinger schrieb:
> This is a SVN patch request.
> 
> Bugtracker references: http://bugs.typo3.org/view.php?id=7452
> 
> Branches: trunk only
> 
> Problem:
> This issue is somehow mentioned in TSRef GIFBUILDER's section
> GIFBUILDER.(GBObj).TEXT and concerns the parameter spacing. TSRef states for
> spacing: "Pixel-distance between letters. This may render ugly!"
> Indeed it will render especially ugly, if you have antialiasing (ie upscaling
> and downscaling again) applied to the TEXT object by niceText or antialiasing
> properties to GIFBUILDER.(GBObj).TEXT.
> It will as render even more "ugly" if you rely on correct determination of the
> image width when using [.w] in XY of the whole GIFBUILDER object, with ugly
> meaning that the resulting "bounding" box of the TEXT object will be generally
> to small.
> 
> Solution:
> Applied patch solves the problem.
> 
> Notes:
> The SVN is still open for bugfixes - am I correct? Thanks for clarification.

Summarizing the rounding error is a nice idea here - it can be compared
to drawing a line with an angle of 30° in computer graphics. When no
antialiasing is available it's handled the same (Bresenham's line
algorithm).

However, there are also some extra spaces even if niceText is not used.
The best thing would be if the text rendering would support character
spacing by default. In general I thing, that there are some flaws in the
niceText disposal in the GIFBUILDER.

I attached a modified version of your patch - but I'm still not really
happy with that...

olly
-- 
Oliver Hader
TYPO3 Release Manager 4.3
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