Draw thick-stroked Beziers by computing the outset quadratic, measuring the error, and subdividing until the error is within a predetermined limit.
To try this CL out, change src/core/SkStroke.h:18 to
#define QUAD_STROKE_APPROXIMATION 1
or from the command line: CPPFLAGS="-D QUAD_STROKE_APPROXIMATION=1" ./gyp_skia
Here's what's in this CL:
bench/BezierBench.cpp : a microbench for examining where the time is going
gm/beziers.cpp : random Beziers with various thicknesses
gm/smallarc.cpp : a distillation of bug skia:2769
samplecode/SampleRotateCircles.cpp : controls added for error, limit, width
src/core/SkStroke.cpp : the new stroke implementation (disabled)
tests/StrokerTest.cpp : a stroke torture test that checks normal and extreme values
The new stroke algorithm has a tweakable parameter:
stroker.setError(1); (SkStrokeRec.cpp:112)
The stroke error is the allowable gap between the midpoint of the stroke quadratic and the center Bezier. As the projection from the quadratic approaches the endpoints, the error is decreased proportionally so that it is always inside the quadratic curve.
An overview of how this works:
- For a given T range of a Bezier, compute the perpendiculars and find the points outset and inset for some radius.
- Construct tangents for the quadratic stroke.
- If the tangent don't intersect between them (may happen with cubics), subdivide.
- If the quadratic stroke end points are close (again, may happen with cubics), draw a line between them.
- Compute the quadratic formed by the intersecting tangents.
- If the midpoint of the quadratic is close to the midpoint of the Bezier perpendicular, return the quadratic.
- If the end of the stroke at the Bezier midpoint doesn't intersect the quad's bounds, subdivide.
- Find where the Bezier midpoint ray intersects the quadratic.
- If the intersection is too close to the quad's endpoints, subdivide.
- If the error is large proportional to the intersection's distance to the quad's endpoints, subdivide.
BUG=skia:723,skia:2769
Review URL: https://codereview.chromium.org/558163005
Allow GM results to be compared across machines and platforms by
standardizing the fonts used by all tests.
This adds runtime flags to DM to use either the system font context (the
default), the fonts in the resources directory ( --resourceFonts ) or a set
of canonical paths generated from the fonts ( --portableFonts ).
This CL should leave the current DM results unchanged by default.
If the portable font data or resource font is missing when DM is run, it
falls back to using the system font context.
The create_test_font tool generates the paths and metrics read by DM
with the --portableFonts flag set, and generates the font substitution
tables read by DM with the --resourceFonts flag set.
If DM is run in SkDebug mode with the --reportUsedChars flag set, it
generates the corresponding data compiled into the create_test_font tool.
All GM tests set their typeface information by calling either
sk_tool_utils::set_portable_typeface or
sk_tool_utils::portable_typeface .
(The former takes the paint, the latter returns a SkTypeface.) These calls
can be removed in the future when the Font Manager can be superceded.
BUG=skia:2687
R=mtklein@google.com
Review URL: https://codereview.chromium.org/407183003
Share command flags between dm and unit tests.
Also, allow dm's core to be included by itself and iOSShell.
Command line flags that are the same (or nearly the same) in DM
and in skia_tests have been moved to common_flags. Authors,
please check to see that the shared common flag is correct for
the tool.
For iOS, the 'tool_main' entry point has a wrapper to allow multiple
tools to be statically linked in the iOSShell.
Since SkCommandLineFlags::Parse can only be called once, these calls
are disabled in the IOS build.
Since the iOS app directory is dynamically assigned a name, use '@' to
select it. (This is the same convention chosen by the Mobile Harness
iOS file system utilities.)
Move the heart of dm.gyp into dm.gypi so that it can be included by
itself and iOSShell.gyp.
Add tools/flags/SkCommonFlags.* to define and declare common
command line flags.
Add support for dm to iOSShell.
BUG=skia:
R=scroggo@google.com, mtklein@google.com, jvanverth@google.com, bsalomon@google.com
Author: caryclark@google.com
Review URL: https://codereview.chromium.org/389653004
Picture serialization is not yet hardened, but it turns out we do need
serialization of SkPictureImageFilter for deferred SVG-on-SVG filters,
since the SkPaints (and thus the SkImageFilters) are serialized by
SkPictureRecord. However, deferred filters are always drawn in the
same process, so we can safely serialize them in this case. We do this
by turning the compile-time check for
SK_ALLOW_PICTUREIMAGEFILTER_SERIALIZATION to a runtime check for
isCrossProcess().
The image filter fuzzer sample was also modified to enable fuzzing
of basic picture image filters (the code had rotted a bit, being behind
an #ifdef that no one sets).
BUG=375162
R=sugoi@google.com
Review URL: https://codereview.chromium.org/311443003
git-svn-id: http://skia.googlecode.com/svn/trunk@15008 2bbb7eff-a529-9590-31e7-b0007b416f81
caryclark
reed
bsalomon
reed
piotaixr
borenet
robertphillips
mtklein
humper
tfarina
senorblanco
Ben Wagner
senorblanco@chromium.org
commit-bot@chromium.org