Adds a method to determine the worst-case number of tessellated line
segments that a path might require, and disables hardware tessellation
if it is more segments than are supported (falling back on indirect
draw shaders).
If the path requires even more segments than are supported by the
indirect draw shaders (1024), we crop the path to the viewport. The
required number of segments is proportional to the square root of the
bounding box's diagonal, so we won't start cropping paths until their
device-space bounding box diagonal is nearly 175,000 pixels long.
Change-Id: I8a9435e70bb93dda3464cc11a3e44fbe511744ae
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/293691
Reviewed-by: Greg Daniel <egdaniel@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
This reverts commit c80ee456ad.
fix: update flutter's gn file to add guard
Change-Id: Iac5171c8475d9a862d06255dab1c6f38f10de2f2
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/291361
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>
This can be done more simply with SkPathRef::Editor::writablePoints.
Change-Id: Icef31bf3a6cc2c8c4ef6da36167c574c73a0d944
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/287497
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Wedges fanning out from the center work fine for relatively simple
paths, but for paths made up of thousands of verbs, a fan is an
inefficient triangulation to give the rasterizer. This CL adds a
tessellation mode that draws the inner polygon and standalone cubics
separately, and triangulates the inner polygon by recursive
subdivision.
This reduces the stencil time from 7.4ms -> 3.0ms on desk_ynevsvg.skp.
Change-Id: Ie56e760d98e6c69e9a97752fe851726f36a7f574
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/265522
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Implements a simple first pass for a path renderer that uses the
classic Red Book "stencil then cover" method, and linearizes curves
with GPU tessellation shaders.
The new path renderer is disabled by default, and can only be enabled
in the viewer UI or by passing the "--pr gtess" flag.
Change-Id: Ic9354952e93c8b108577961760b4f0daa82d35aa
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/261715
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
