In rare cases, floating point error causes the tesselator to add the
same Vertex to more than one Poly on the same side. This was not a big
problem when we were allocating new vertices when constructing Polys,
but after https://codereview.chromium.org/2029243002 it causes more serious
issues, since each Edge can only belong to two Polys, and violating this
condition messes up the linked list of Edges used for left & right Polys
and the associated estimated vertex count.
The fix is to simply let the first Poly win, and skip that vertex for
subsequent Polys. Since this only occurs in cases where vertices are very
close to each other, it should have little visual effect.
This is also exercised by Nebraska-StateSeal.svg.
BUG=skia:5636
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2259493002
Review-Url: https://codereview.chromium.org/2259493002
Converts GrClip to an abstract base class and adds a "GrFixedClip"
implementation. GrFixedClip denotes a clip implemented with fixed-
function hardware. GrFixedClip allows us to remove the stateful
"fClipMode" member from GrClipMaskManager, and in the future will
be able to nicely encapsulate window rectangles.
After this change GrClipMaskManager is just a wrapper around
GrDrawTarget. We may want to consider removing it altogether.
BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1971343002
Review-Url: https://codereview.chromium.org/1971343002
Initialize glGenTexture, glGenBuffer call id buffer items to zero before
calls. Otherwise it's not easy to check if the call succeeded or not.
Assert the rule in debug gl context.
Make TesselatingPathRendererTests use debug gl context. It exercises
some of the GenBuffers call sites.
Review URL: https://codereview.chromium.org/1514033002
Use DEF_GPUTEST_FOR_*_CONTEXT macros to obtain the
test GPU context.
Makes changing the context -related classes easier,
since not all tests need to be changed.
BUG=skia:2992
Review URL: https://codereview.chromium.org/1448873002
This shouldn't really make any difference but allocating and holding on to a GrRenderTarget for each test target generates image differences for Mali GPUs. This CL allows an existing render target to be used for the test target.
TBR=bsalomon@google.com
Review URL: https://codereview.chromium.org/1447113002
Move line dashing logic from GrContext::drawPath to
GrDashLinePathRenderer. This makes it possible to let path renderers render arbitrary dashed paths.
End goal is to implement dashing in GrStencilAndCoverPathRenderer.
Review URL: https://codereview.chromium.org/1100073003
More nullptr checks for factories I have added.
Other checks more Yoda-like I have made. (Skia style this is.)
BUG=skia:
Review URL: https://codereview.chromium.org/1086393004
Sometimes, the intersection returned by check_intersection() is
out-of-bounds for both edges (above both tops or below both bottoms)
due to floating-point inaccuracy. This causes split_edge() to create a
tiny negative-length edge on one side (which would then assert).
Although we could safely remove this assert and allow the negative
length edge to be removed, it's faster/safer to simply avoid its
creation in the first place by adjusting one edge to the other edge's
endpoint.
Added a new unit test to exercise this case.
Review URL: https://codereview.chromium.org/968993002
This path renderer converts paths to linear contours, resolves intersections via Bentley-Ottman, implements a trapezoidal decomposition a la Fournier and Montuno to produce triangles, and renders those with a single draw call. It does not currently do antialiasing, so it must be used in conjunction with multisampling.
A fair amount of the code is to handle floating point edge cases in intersections. Rather than perform exact computations (which would require arbitrary precision arithmetic), we reconnect the mesh to reflect the intersection points. For example, intersections can occur above the current vertex, and force edges to be merged into the current vertex, requiring a restart of the intersections. Splitting edges for intersections can also force them to merge with formerly-distinct edges in the same polygon, or to violate the ordering of the active edge list, or the active edge state of split edges.
BUG=skia:
Review URL: https://codereview.chromium.org/855513004
