This is a reland of 75e1f4c028
Original change's description:
> Lift recursive curve culling out of tessellators
>
> We need recursive chopping/culling logic in order to draw
> astronomically large paths. But rather than do that at the same time
> the tessellators chop curves, this CL moves that logic into an
> SkPath -> SkPath transformation that runs ahead of time (and only if
> the path is extremely large to begin with). This will enable us to
> remove recursion from the tessellators and quickly determine ahead of
> time the size of buffers they need.
>
> Bug: skia:12524
> Change-Id: Ib2800fb23054f1548501811203173e58273fbc83
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/463936
> Commit-Queue: Chris Dalton <csmartdalton@google.com>
> Reviewed-by: Greg Daniel <egdaniel@google.com>
Bug: skia:12524
Change-Id: Idf54f0c2bddaaddc9fc17bee99c910f3961682a5
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/465361
Reviewed-by: Greg Daniel <egdaniel@google.com>
Auto-Submit: Chris Dalton <csmartdalton@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
This is a reland of 8a2a020ef4
Original change's description:
> Create a common Tessellation.h header
>
> This header and corresponding implementation will contain common
> definitions and subroutines for tessellation code.
>
> Bug: skia:12524
> Change-Id: Ib29b444177f284acb88a3d5644936674c48c0b89
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/463437
> Commit-Queue: Chris Dalton <csmartdalton@google.com>
> Reviewed-by: Greg Daniel <egdaniel@google.com>
Bug: skia:12524
Change-Id: I874fed63cdab50df841e8a5d25d8c822690b5af8
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/464294
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
This reverts commit 8a2a020ef4.
Reason for revert: breaking chrome roll. Needs change in chrome to land first
Original change's description:
> Create a common Tessellation.h header
>
> This header and corresponding implementation will contain common
> definitions and subroutines for tessellation code.
>
> Bug: skia:12524
> Change-Id: Ib29b444177f284acb88a3d5644936674c48c0b89
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/463437
> Commit-Queue: Chris Dalton <csmartdalton@google.com>
> Reviewed-by: Greg Daniel <egdaniel@google.com>
Bug: skia:12524
Change-Id: Ifd7e81eed8c337506d67ecd0fd2501eedf2e4408
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/464297
Auto-Submit: Greg Daniel <egdaniel@google.com>
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
This reverts commit 75e1f4c028.
Reason for revert: need to revert parent CL
Original change's description:
> Lift recursive curve culling out of tessellators
>
> We need recursive chopping/culling logic in order to draw
> astronomically large paths. But rather than do that at the same time
> the tessellators chop curves, this CL moves that logic into an
> SkPath -> SkPath transformation that runs ahead of time (and only if
> the path is extremely large to begin with). This will enable us to
> remove recursion from the tessellators and quickly determine ahead of
> time the size of buffers they need.
>
> Bug: skia:12524
> Change-Id: Ib2800fb23054f1548501811203173e58273fbc83
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/463936
> Commit-Queue: Chris Dalton <csmartdalton@google.com>
> Reviewed-by: Greg Daniel <egdaniel@google.com>
Bug: skia:12524
Change-Id: Ib075e8398767fd7b9f49e50ecee98ce47a2ad6b1
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/464296
Auto-Submit: Greg Daniel <egdaniel@google.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Commit-Queue: Greg Daniel <egdaniel@google.com>
We need recursive chopping/culling logic in order to draw
astronomically large paths. But rather than do that at the same time
the tessellators chop curves, this CL moves that logic into an
SkPath -> SkPath transformation that runs ahead of time (and only if
the path is extremely large to begin with). This will enable us to
remove recursion from the tessellators and quickly determine ahead of
time the size of buffers they need.
Bug: skia:12524
Change-Id: Ib2800fb23054f1548501811203173e58273fbc83
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/463936
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
This header and corresponding implementation will contain common
definitions and subroutines for tessellation code.
Bug: skia:12524
Change-Id: Ib29b444177f284acb88a3d5644936674c48c0b89
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/463437
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
This class is only meant to be used with Wang's formulas, so it
belongs in their name namespace.
Bug: skia:12524
Change-Id: Ib1667781b947a7f052af103b7bf9084d09a690de
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/461567
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
Tessellation code can just exist in the skgpu namespace.
Bug: skia:12524
Change-Id: I44d473c5f82d608bb6cd3bb9df239c4f4028da4f
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/461557
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
We are making src/gpu/tessellate independent of v1, and more represent
math and types that just know how to tessellate, so this seems like the
right place again for this file.
Bug: skia:12524
Change-Id: I773de3c0f93a57ce7ee16b44480667013f32ebd5
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/459136
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
This is just a bunch of renaming, and for now the tessellate/shaders
directory remains untouched. The next steps will be to clean up and
remove all Ganesh v1 dependencies from tessellation.
Bug: skia:12524
Change-Id: I8cc166c0c78f9fb160de807131fa53fcc0765818
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/458876
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
Rearranges the algebra to use "precision". This makes it consistent
with the other formulas and removes the need for the caller to think
about inverting its precision value.
Bug: skia:10419
Change-Id: I186d03393952983e86b0bef69e1f89f86cdbb423
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/414616
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Tyler Denniston <tdenniston@google.com>
- most of the small diffs are because I moved GrWangsFormula.h out
of the tessellate/ directory and into the geometry/ directory since
it's more general than HW tessellation.
The previous implementation was based on the heuristic that the distance
from the true curve to the line segment would be divided by 4 every time
the curve was recursively subdivided. This was a reasonable
approximation if the curve had balanced curvature on both sides of the
split. However, in the case of the new GM's curve, the left half was
already very linear and the right half had much higher curves.
This lead to the approximation reporting fewer points than required.
Theoretically, those few points that weren't utilized by the left half
of the curve could have been made available to the right half, but the
implementation of that would be tricky.
Instead, it now uses Wang's formula to compute the number of points.
Since recursive subdivision leads to linearly spaced samples assuming it
can't stop early, this point count represents a valid upper bound on
what's needed. It also then ensures both left and right halves of a
curve have the point counts they might need w/o updating the
generation implementations. However, since the recursive point
generation exits once each section has reached the error tolerance, in
scenarios where the prior approximation was reasonable, we'll end up
using fewer points than reported by Wang's. Hopefully that means there
is negligible performance regression since we won't be increasing
vertex counts by that much (except where needed for correctness).
Bug: skia:11886
Change-Id: Iba39dbe4de82011775524583efd461b10c9259fe
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/405197
Reviewed-by: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Michael Ludwig <michaelludwig@google.com>
- Treat randomly generated control points as pre-projected
- Use double-precision conic evaluation for "within tolerance" test.
This allows us to test with larger magnitude control points (the
SkConic/SkGeometry single-precision functions lose too much accuracy).
Bug: skia:10419
Change-Id: Iba0915dccb50131e1a1b28a7d556863497f636e9
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/367057
Commit-Queue: Tyler Denniston <tdenniston@google.com>
Reviewed-by: Chris Dalton <csmartdalton@google.com>
Also add a unit test that the vectorized version equals the reference
implementation.
Bug: skia:10419
Change-Id: I4d165fd45532e9ec468565d0637fb769b51f5fcd
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/345122
Commit-Queue: Tyler Denniston <tdenniston@google.com>
Reviewed-by: Chris Dalton <csmartdalton@google.com>
Initial data suggests that the non-rational Wang's formula does not
form an upper bound for the rational case, so additional work is needed
to handle them. Note this new formula is not actually due to Wang,
but is an analogue.
The version added in this CL is for cubic rationals because the current
tessellation code promotes all curve segments to cubic rationals for
ease. If we end up using this approach, it would be likely simpler and
faster to implement the degree-2 version and handle conics separately
during tessellation.
From:
J. Zheng, T. Sederberg. "Estimating Tessellation Parameter Intervals for
Rational Curves and Surfaces." ACM Transactions on Graphics 19(1). 2000.
Bug: skia:10419
Change-Id: Ie02e229c089541ece05c7502217b1ef5d4799b52
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/337720
Commit-Queue: Tyler Denniston <tdenniston@google.com>
Reviewed-by: Chris Dalton <csmartdalton@google.com>
Just verify that the max error on any of the intervals after splitting
is less than the specified tolerance. Looks like we're running into
some FP precision issues with large coord values, so I'm limiting the
max multiplier to 2^15 in this test.
Bug: skia:10419
Change-Id: I39e76dca5f77389833ba3c94930e6b67c2b1bc97
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/340116
Reviewed-by: Chris Dalton <csmartdalton@google.com>
Commit-Queue: Tyler Denniston <tdenniston@google.com>
We finally have a reference and derivation of Wang's formula, thanks to
tdenniston@. And it turns out that the formula we had been using for
cubics wasn't quite right. It was overly conservative for certain types
of curves.
This CL fixes the incorrect cubic formulas and adds a citation to the
"Pyramid Algorithms" book. We should now be getting by with fewer linear
segments.
Bug: skia:10419
Change-Id: Ib850c7b4d17b8d9f9abed800cc7cb5f074df6e17
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/331156
Reviewed-by: Tyler Denniston <tdenniston@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Bug: skia:10419
Change-Id: I1544113b6ea2327674a48a0430146a859a547723
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/322796
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
Adds various optimizations to GrWangsFormula as well as "pow4" variants
of the formula that are quicker than the standard and/or log2 versions.
Uses the pow4 variants in GrStrokePatchBuilder.
Bug: skia:10419
Change-Id: I8478582df5296b088d25808bcaeb93107ff20797
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/318954
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Other code outside this namespace will want to use this method soon.
Bug: skia:10419
Change-Id: Ib155f224866fd333b8f9a4b78e6c9e51ac0600df
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/311936
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
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 is a reland of e278e1c1c7
Original change's description:
> Add an implementation and log2 variants for Wang's formula
>
> Wang's formulas for cubics and quadratics (1985) tell us how many line
> segments a curve must be chopped into when tessellating. This CL adds
> an implementation along with optimized log2 variants, as well as tests
> and a benchmark.
>
> Change-Id: I3f777b8d0312c57c3a1cc24307de5945c70be287
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/288321
> Reviewed-by: Brian Salomon <bsalomon@google.com>
> Commit-Queue: Chris Dalton <csmartdalton@google.com>
TBR=bsalomon@google.com
Change-Id: Ie3822c62439fc579a59ea8adb49583224de41aa5
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/289680
Reviewed-by: Chris Dalton <csmartdalton@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
This reverts commit e278e1c1c7.
Reason for revert: i think we need to do that add with an unsigned, or test instead of always += (1<<23)-1.
Original change's description:
> Add an implementation and log2 variants for Wang's formula
>
> Wang's formulas for cubics and quadratics (1985) tell us how many line
> segments a curve must be chopped into when tessellating. This CL adds
> an implementation along with optimized log2 variants, as well as tests
> and a benchmark.
>
> Change-Id: I3f777b8d0312c57c3a1cc24307de5945c70be287
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/288321
> Reviewed-by: Brian Salomon <bsalomon@google.com>
> Commit-Queue: Chris Dalton <csmartdalton@google.com>
TBR=bsalomon@google.com,brianosman@google.com,csmartdalton@google.com
Change-Id: I24dfd8549054b632f38f7b05b4d857b640cf5cd1
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/289658
Reviewed-by: Mike Klein <mtklein@google.com>
Commit-Queue: Mike Klein <mtklein@google.com>
Wang's formulas for cubics and quadratics (1985) tell us how many line
segments a curve must be chopped into when tessellating. This CL adds
an implementation along with optimized log2 variants, as well as tests
and a benchmark.
Change-Id: I3f777b8d0312c57c3a1cc24307de5945c70be287
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/288321
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
