AO_compare_and_swap_full() doesn't have the same semantic as
_cairo_atomic_int_cmpxchg(). The former returns a TRUE on success
FALSE otherwise while the later returns the atomic value.
Previously target device offsets were applied in cairo-surface.c which
could cause bugs when paths were taken as fallbacks, as for example
pointed out by ade55037ff and quick-fixed
by 79190d8985. The quick-fix is now
unnecessary and was removed.
Gah, that was a horrible mistake. It was a flawed hack to create Pixmaps
of the correct depth when cloning patterns for blitting to the xlib
backend. However, it had the nasty side-effect of discarding alpha when
targeting Window surfaces. The correct solution is to simply correct the
Pixmap of the desired depth and render a matching pattern onto the
surface - i.e. a reversal the current acquire -> clone. See the
forthcoming revised xcb backend on how I should have done it originally.
Honour the incoming surface format when we are asked to create a similar
surface with identical content. The goal of
cairo_surface_create_similar() is to create an intermediate with similar
characteristics to the original that can be used in place of the
original and be quick to copy to the original. Matching the format for
the same content, ensures that the blits between the two need only be a
memcpy.
The goal is to create a similar surface with an identical format to
maximise performance in the subsequent blit, e.g. the xlib backend could
make the similar surface with an identical depth and so use the core
protocol, or the image surface could indeed make an identical copy so
that pixman only has to do a fast memcpy. As there is no direct method
to specify such a clone, we ask the backend for a similar surface of
identical content, and trust that the semantics are clear enough for the
intent to obvious.
Otherwise, it was disrupting my attempts to release a snapshot, (since
it doesn't respect CAIRO_TEST_TARGET=" " and not run like most of the
tests do).
Turns out we were passing suncc warning suppression flags to gcc
by mistake since -e<entry point> is actually a valid option for
gcc. This caused the -erroff=E_ENUM_TYPE_MISMATCH_ARG and other
-erroff options to be passed to the linker. In the normal case
of a GNU ld linker this doesn't matter since it ignores bogus
entry points, but the GNU gold linker replaces a bogus entry
point with NULL. This patch makes the CAIRO_CC_TRY_FLAG()
check stricter by testing that the flag doesn't interfere with
linking executables.
_cairo_surface_fallback_paint() attempts to avoid a clipped operation if
we can convert the paint into a fill of the clipmask. However by calling
_cairo_surface_fill() we incur a double application of device offset to
the source, triggering various failures.
Company spotted this and managed to extract an excellent minimal test
case, test/clip-device-offset. This commit fixes that failure.
As noted in the comments we could also compute the pattern extents for
gradients with CAIRO_EXTEND_NONE under certain circumstances, i.e.
radial gradients and device axis aligned linear gradients.
XCB avoids the dreaded abort on XError mechanism by forcing the client
to perform deferred error checking. So do so. This allows us to combine
the fire-and-forget rendering model with accurate error checking,
without killing the client or mixing our errors with theirs.
XCB for the win!
Replaying a meta surface can be achieved by using it as a source for a
cairo_paint() so exporting a separate API is unnecesary and confusing.
So after consulting Chris and Carl, we decided to remove the function
again.
Provide default DocumentMedia and PageMedia DSC comments if the user
does not specify them using cairo_ps_surface_dsc_comment(). This is
required so that PostScript viewers such as gv use the correct page
size.
Benjamin Otte pointed out the error of my ways that a clear on a
cairo_image_surface_create_for_data() was not working. This is because I
modified the image surface to skip clears when it knows the target data
has been cleared. This flag must be reset when the user interacts with
the surface, such as providing the initial surface data.
Hunting for a known bug in the xlib backend where it invalidly converts
an argb32 source to rgb24. However, this does not appear to be that bug,
but still a useful exercise nevertheless.