This is porting the relevant part of a previous upstream commit[1] to
align the behavior of our bundled libgd with upstream. It should be
noted that this only works if the image actually has a transparent
color.
[1] <4770e2b2d5>
Closes GH-17351.
We port the upstream fix[1], and also revert commit a3383ac3d7[2] which
is now obsolete, and also not part of libgd. Especially the change to
gd.png.c was at best a half-baked optimization.
[1] <a24e96f019>
[2] <a3383ac3d7>
Closes GH-7402.
The fix for PHP bug 43828[1] changed the algorithm from drawing filled
pies from drawing multiple triangles to drawing a single polygon. Due
to quirks of the filled polygon drawing algorithm, we had to filter out
extraneous vertices. This lead, however, to a bug regarding displaced
starting and ending points near 90° and 270° degrees, which we fix by
reinserting these vertices if they had been removed.
This fix is a port of libgd/libgd@1406b1a.
[1] <https://bugs.php.net/bug.php?id=43828>
We must not draw anti-aliased lines on palette images, because that is
not supported by `gdImageSetAAPixelColor()` and it wouldn't make much
sense to support it, due to the limitation to at most 256 colors.
* PHP-7.1:
Fixed bug #73418 Integer Overflow in "_php_imap_mail" leads to crash
Fixed bug #73418 Integer Overflow in "_php_imap_mail" leads to crash
Fix#72696: imagefilltoborder stackoverflow on truecolor images
Fix#72482: Ilegal write/read access caused by gdImageAALine overflow
Fix bug #73144 and bug #73341 - remove extra dtor
remove unreferenced var came in with merge
Fix bug #73331 - do not try to serialize/unserialize objects wddx can not handle
Fix#72696: imagefilltoborder stackoverflow on truecolor images
Fix#72482: Ilegal write/read access caused by gdImageAALine overflow
fix version
set versions
Fix bug #73144 and bug #73341 - remove extra dtor
Fix bug #73331 - do not try to serialize/unserialize objects wddx can not handle
We must not allow negative color values be passed to
gdImageFillToBorder(), because that can lead to infinite recursion
since the recursion termination condition will not necessarily be met.
(cherry picked from commit 863d37ea66)
Instead of rolling our own bounds check we use clip_1d() as it's done
in gdImageLine() and in external libgd. We must not pass the image
width and height, respectively, but rather the largest ordinate value
that is allowed to be accessed, i.e. width-1 and height-1,
respectively.
(cherry picked from commit 6499581af7)
There's no need anymore to call an own error handler directly. Instead we
register our error handler and call libgd's error functions (which will
forward). We do this regardless of compiling with the bundled or an external
libgd.
gdImageOpenPolygon() has been introduced with líbgd 2.0.29, so we finally
add a PHP binding for it, and port the respective libgd functionality to
PHP's bundled libgd.
gdLayerMultiply() has been introduced in libgd 2.1.1, and as such would have
been already available for imagelayereffect() with a system libgd. We port
the respective code to the bundled libgd, and also make IMG_EFFECT_MULTIPLY
available to userland.
Instead of rolling our own in the bundled libgd, we use libgd's anti-aliased
drawing API. This way imageantialias() is also available, when built against
a system libgd.
Curiously, while the external GD claims "just a few vestiges after switching
to the fast, memory-cheap implementation from PHP-gd", that stuff was still
in the bundled GD.
* integrate gd_arc.c into gd.c (as of gd-2.1.0-alpha1)
* rename gd_color.c to gd_color_match.c (as of gd-2.1.0-alpha1)
* remove mathmake.c (as of GD_2_0_34RC1)
* rename xbm.c to gd_xbm.c (as of gd-2.1.0-alpha1)
The earlier gdAlphaBlend() has been replaced with commit 1286d9e2, and has
been renamed to gdAlphaBlendOld(). The old function is, however, not used,
and after more than 9 years we're pretty sure we won't need it anymore.
No pixel of a filled arc must ever be drawn multiple times. Otherwise we get
artifacts regarding transparency. That happens with the current
implementation of gdImageFilledArc() unless gdChord or gdNoFill are set.
When gdPie is set, however, the filled arc is drawn in wedges, which are
polygons of three points, and so some overlap is natural.
To resolve the issue, we stick with the current algorithm of calculating the
wedges, but instead of drawing each polygon separately, we put the relevant
points in a large array, and draw a single polygon. That also is supposed to
improve the performance considerably.
Note that this modification will change the results when gdImageSetStyle()
or gdImageSetBrush() are used, but we believe that this modification is also
an improvement in this regard, even though it still might not make much
sense to use these functions with gdImageFilledArc().
The respective fix for libgd is
<e7e20d6>.
