skia2/gm/crbug_1177833.cpp
Brian Salomon 659e71f474 Reland "Fix issues with insetting and outsetting quads."
This is a reland of 4a281dc8ee

Original change's description:
> Fix issues with insetting and outsetting quads.
>
> Need more degrees of freedom when moving 3D points to project to 2D
> points that don't fall on the projected quad edges.
>
> Need to check geometry subset in shader to avoid positive coverage in
> outset quads with nearly parallel edges.
>
> Bug: chromium:1177833
> Change-Id: I0759382d9221ba44aacd537254e08d9f2716a6af
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/372196
> Reviewed-by: Michael Ludwig <michaelludwig@google.com>
> Commit-Queue: Brian Salomon <bsalomon@google.com>

Bug: chromium:1177833
Change-Id: Icf2b11334489c12f30e792526093c0d4bbaca5e0
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/375058
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
2021-02-25 17:44:12 +00:00

99 lines
5.5 KiB
C++

/*
* Copyright 2021 Google LLC
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "gm/gm.h"
#include "include/core/SkCanvas.h"
#include "include/core/SkMatrix.h"
#include "include/core/SkRect.h"
// Bad quads dumped from SkiaRenderer in crbug.com/1178833. These should all draw as really thin
// lines.
DEF_SIMPLE_GM(crbug_1177833, canvas, 400, 400) {
canvas->clear(SK_ColorBLACK);
canvas->translate(-700, -700);
// This quad had two issues. The inset collapsed the inner 2D projected quad to a point but
// didn't enable enough degrees of freedom to adjust the 4 3D points to project to that point.
// Also, the outset produced a 2D projected point far away from the original quad but the
// shader was not checking the geometric subset and so pixels far away from the projection of
// the quad would have positive coverage.
{
canvas->save();
canvas->concat(SkMatrix::MakeAll(SkBits2Float(0xbf79250e), SkBits2Float(0x3e9da860), SkBits2Float(0x44914c8a),
SkBits2Float(0xbf982962), SkBits2Float(0xbf280002), SkBits2Float(0x44c3116e),
SkBits2Float(0xba9bfe62), SkBits2Float(0x39d10455), SkBits2Float(0x3fc9b377)));
SkRect rect = {SkBits2Float(0x00000000),
SkBits2Float(0x00000000),
SkBits2Float(0x40a00000),
SkBits2Float(0x43560000)};
SkPoint clip[4] = {{SkBits2Float(0x409fff57), SkBits2Float(0x40c86a18)},
{SkBits2Float(0x409fff57), SkBits2Float(0x4314dc8c)},
{SkBits2Float(0x407f6b0d), SkBits2Float(0x43157fff)},
{SkBits2Float(0x4040859c), SkBits2Float(0x43140374)}};
SkCanvas::QuadAAFlags aaFlags = static_cast<SkCanvas::QuadAAFlags>(0x00000002);
SkColor4f color = {SkBits2Float(0x3f6eeef0),
SkBits2Float(0x3f6eeef0),
SkBits2Float(0x3f6eeef0),
SkBits2Float(0x3f800000)};
SkBlendMode mode = static_cast<SkBlendMode>(0x00000003);
canvas->experimental_DrawEdgeAAQuad(rect, clip, aaFlags, color, mode);
canvas->restore();
}
// This quad also exposed the inset collapse to a point without enough degrees of freedom issue.
canvas->save();
canvas->translate(-300, 0);
{
canvas->save();
canvas->concat(SkMatrix::MakeAll(SkBits2Float(0x3f54dd8a), SkBits2Float(0xbf9096a4), SkBits2Float(0x447eae34),
SkBits2Float(0x3f3f6905), SkBits2Float(0xbe5208ba), SkBits2Float(0x4418118b),
SkBits2Float(0x3aa134a1), SkBits2Float(0xb93ef249), SkBits2Float(0x3f580bd4)));
SkRect rect = {SkBits2Float(0x00000000),
SkBits2Float(0x00000000),
SkBits2Float(0x40a00000),
SkBits2Float(0x43560000)};
SkPoint clip[4] = {{SkBits2Float(0x40a0000e), SkBits2Float(0x40c86b5a)},
{SkBits2Float(0x40a0001e), SkBits2Float(0x4314dd5f)},
{SkBits2Float(0x407f76eb), SkBits2Float(0x431580c2)},
{SkBits2Float(0x404092e7), SkBits2Float(0x43140445)}};
SkCanvas::QuadAAFlags aaFlags = static_cast<SkCanvas::QuadAAFlags>(0x00000002);
SkColor4f color = {SkBits2Float(0x3f6eeef0),
SkBits2Float(0x3f6eeef0),
SkBits2Float(0x3f6eeef0),
SkBits2Float(0x3f800000)};
SkBlendMode mode = static_cast<SkBlendMode>(0x00000003);
canvas->experimental_DrawEdgeAAQuad(rect, clip, aaFlags, color, mode);
canvas->restore();
}
canvas->restore();
// This quad exposed a similar issue to the point issue above, but when collapsing to a
// triangle. When a 2D quad edge collapsed from insetting we'd replace it with a point off of
// its adjacent edges. We need to ensure the code that moves the 3D point that projects to
// the 2D point has 2 degrees of freedom so it can find the correct 3D point.
{
canvas->save();
canvas->concat(SkMatrix::MakeAll(SkBits2Float(0x3f54b255), SkBits2Float(0x3eb5a94d), SkBits2Float(0x443d7419),
SkBits2Float(0x3f885d66), SkBits2Float(0x3f5a6b9c), SkBits2Float(0x443c7334),
SkBits2Float(0x3aa95ea5), SkBits2Float(0xb8a1391e), SkBits2Float(0x3f84dde5)));
SkRect rect = {SkBits2Float(0x00000000),
SkBits2Float(0x00000000),
SkBits2Float(0x40a00000),
SkBits2Float(0x43100000)};
SkPoint clip[4] = {{SkBits2Float(0x405a654c), SkBits2Float(0x42e8c790)},
{SkBits2Float(0x3728c61b), SkBits2Float(0x42e7df31)},
{SkBits2Float(0xb678ecc5), SkBits2Float(0x412db4e0)},
{SkBits2Float(0x4024b2ad), SkBits2Float(0x413ab3ed)}};
SkCanvas::QuadAAFlags aaFlags = static_cast<SkCanvas::QuadAAFlags>(0x00000004);
SkColor4f color = {SkBits2Float(0x3f800000),
SkBits2Float(0x3f800000),
SkBits2Float(0x3f800000),
SkBits2Float(0x3f800000)};
SkBlendMode mode = static_cast<SkBlendMode>(0x00000003);
canvas->experimental_DrawEdgeAAQuad(rect, clip, aaFlags, color, mode);
canvas->restore();
}
}