Jeff Muizelaar noted that the treatment of edges differed with firefox's
canvas definition, which considers a point on any edge as inside. The
current implementation has a similar definition to that of flash, for
which the top and right edges are outside. Arguably, firefox has the more
intuitive definition here...
If the backend cannot create a similar surface to hold the image, then
report back the failure before embarking upon an infinite recursion.
The UNSUPPORTED return should percolate up through the call stack and
trigger a fallback.
Bug 19251: --enable-win32=yes and --enable-win32-font=no causes
compilation failure
[https://bugs.freedesktop.org/show_bug.cgi?id=19251]
Wrap use of the win32 font backend within win32-printing-surface within
CAIRO_HAS_WIN32_FONT ifdefs to prevent compilation failure if the user
explicitly disables the win32 font backend.
As an aide to tracking down the source of uninitialised reads, run
VALGRIND_CHECK_MEM_IS_DEFINED() over the contents of image surfaces at the
boundary between backends, e.g. upon setting a glyph image or acquiring
a source image.
test/invalid-matrix deliberately feeds garbage into the API to test our
error detection. This causes FPE to be raised during the course of the
test - so they are deliberately disable for the duration. However, the
exceptions were not being cleared and so the FPE could be triggered on
the next floating point operation. This was being masked during make check,
by the fact that each test is run in its own forked process and was only
observed when multiple tests were run in foreground mode.
The test suite depends upon many external factors and in order to achieve
a pass, your system must match that upon which the reference images were
generated. Add a note to read test/README in case of failures so that the
casual user is not unduly alarmed by cairo reportedly failing.
Damian Frank noted
[http://lists.cairographics.org/archives/cairo/2009-May/017095.html]
a performance problem with an older XServer with an
unaccelerated composite - similar problems will be seen with non-XRender
servers which will trigger extraneous fallbacks. The problem he found was
that painting an ARGB32 image onto an RGB24 destination window (using
SOURCE) was going via the RENDER protocol and not core. He was able to
demonstrate that this could be worked around by declaring the pixel data as
an RGB24 image. The issue is that the image is uploaded into a temporary
pixmap of matching depth (i.e. 32 bit for ARGB32 and 24 bit for RGB23
data), however the core protocol can only blit between Drawables of
matching depth - so without the work-around the Drawables are mismatched
and we either need to use RENDER or fallback.
This patch adds a content mask to _cairo_surface_clone_similar() to
provide the extra bit of information to the backends for when it is
possible for them to drop channels from the clone. This is used by the
xlib backend to only create a 24 bit source when blitting to a Window.
Bug 21706 -- zombie ft_font_face / ft_unscaled_font mutual
referencing problems
[http://bugs.freedesktop.org/show_bug.cgi?id=21706]
There can be more than one zombie font_face belonging to an unscaled_font,
but only the first is destroyed. This leaks the client's FT_Face
(and associated font data) as release of the FT_Face depends on release
of the font_face.
(The reason why Firefox ends up with two different font_faces for one
unscaled_font is that load_flags for faces with artificial oblique have
FT_LOAD_NO_BITMAP set.
https://bugzilla.mozilla.org/show_bug.cgi?id=486974)
Also it's possible for _cairo_ft_font_face_create to pull out a zombie
font_face from the unscaled_font, which would crash
_cairo_ft_font_face_scaled_font_create, as that expects non-null
font_face->unscaled (if !font-face->pattern).
I broke the ability for the ft font backend to resolve patterns whilst
fixing the font creation to propagate the error status from fontconfig
(be27e8). By adjusting the sequence of error checks we do not confuse
the absence of a match with a fatal error and thereby restoring the
lazy pattern resolution whilst ensuring error propagation.
I was hoping for a bigger win than this, but cairogears is now significantly
faster than it was with just traps. One potential problem is that adding
src texture coordinates blew up vertex size from 12 bytes to 20, and we're
emitting quite a few vertices. There's plenty of hope for the future,
though: With shaders we could remove the 2 new texcoords again by stuffing a
position to source coordinate transformation matrix in constants. Then
with EXT_geometry_shader4 plus EXT_gpu_shader4 we should be able to get the
24 bytes for 2 vertices down to 16 or less.
This is a minor performance regression over software, but is the basis for
not rasterizing the geometry into a temporary mask, which should be a
significant win.
This appears to be no performance difference in cairogears versus the traps
fallback before, but is a step towards handing the information off to the
hardware.
Gl defaults to NEAREST_MIPMAP_LINEAR on new texture objects.
This should save space or bandwidth with DRI drivers, as they'll use the
parameter as a hint, and then not have to either fix up later or waste
space for unused mipmap levels.
Simply request a surface with a similar content to the source image when
uploading pixel data. Failing to do so prevents using a 16-bit (or
otherwise non-standard pixman image format) window as a source - in fact
it will trigger an infinite recursion.
Currently the surface snapshotting attempts to clone the source using a
new surface of identical format. This will raise an error if the source is
an unusual xserver, for example one operating at 16bpp. The solution to
this is to create the surface using the content type rather than the
format (as elsewhere within the code base). However, we also wish to
preserve FORMAT_A1 (which is lost if we only choose the format based on
_cairo_format_from_content) as the various backends may be able to
trivially special case such bitmaps.
It is possible for cairo_surface_write_to_png() to acquire a non-standard
image surface when, for example, we try to dump a low bit-depth XServer.
Handle this scenario by coercing the unknown image format to a standard
type via pixman.
Add a variation of test-fallback-surface that forces the use of a 16-bit
pixman format code instead of the standard 32-bit types. This creates an
image surface akin to the fallbacks used with low bit-depth xservers.
