diff options
author | Mike Reed <reed@google.com> | 2018-01-30 10:12:22 -0500 |
---|---|---|
committer | Skia Commit-Bot <skia-commit-bot@chromium.org> | 2018-01-30 15:56:35 +0000 |
commit | 63227ca63b09ad534b52b1b1957202ab18aa53f7 (patch) | |
tree | d806fb6ce3fc95d4c08595943239455279f1ff57 | |
parent | ab2621d3e2d2055096b9fbebf16ee443e4ea90fb (diff) |
handle clipping large triangles
originally found by fuzzer.
Bug: skia:
Change-Id: I45007a619f13936153c0db8a60b3631a2c9db20c
Reviewed-on: https://skia-review.googlesource.com/101741
Reviewed-by: Cary Clark <caryclark@google.com>
Commit-Queue: Mike Reed <reed@google.com>
-rw-r--r-- | src/core/SkScan_Path.cpp | 14 | ||||
-rw-r--r-- | tests/VerticesTest.cpp | 30 | ||||
-rw-r--r-- | tools/sk_pixel_iter.h | 61 |
3 files changed, 103 insertions, 2 deletions
diff --git a/src/core/SkScan_Path.cpp b/src/core/SkScan_Path.cpp index f2a18b631e..6234afe873 100644 --- a/src/core/SkScan_Path.cpp +++ b/src/core/SkScan_Path.cpp @@ -759,9 +759,19 @@ void SkScan::FillTriangle(const SkPoint pts[], const SkRasterClip& clip, } SkRect r; - SkIRect ir; r.set(pts, 3); - r.round(&ir); + // If r is too large (larger than can easily fit in SkFixed) then we need perform geometric + // clipping. This is a bit of work, so we just call the general FillPath() to handle it. + // Use FixedMax/2 as the limit so we can subtract two edges and still store that in Fixed. + const SkScalar limit = SK_MaxS16 >> 1; + if (!SkRect::MakeLTRB(-limit, -limit, limit, limit).contains(r)) { + SkPath path; + path.addPoly(pts, 3, false); + FillPath(path, clip, blitter); + return; + } + + SkIRect ir = r.round(); if (ir.isEmpty() || !SkIRect::Intersects(ir, clip.getBounds())) { return; } diff --git a/tests/VerticesTest.cpp b/tests/VerticesTest.cpp index 399aba2f21..f55adb0ed3 100644 --- a/tests/VerticesTest.cpp +++ b/tests/VerticesTest.cpp @@ -5,7 +5,10 @@ * found in the LICENSE file. */ +#include "SkCanvas.h" +#include "SkSurface.h" #include "SkVertices.h" +#include "sk_pixel_iter.h" #include "Test.h" static bool equal(const SkVertices* v0, const SkVertices* v1) { @@ -86,3 +89,30 @@ DEF_TEST(Vertices, reporter) { } } } + +static void fill_triangle(SkCanvas* canvas, const SkPoint pts[], SkColor c) { + SkColor colors[] = { c, c, c }; + auto verts = SkVertices::MakeCopy(SkVertices::kTriangles_VertexMode, 3, pts, nullptr, colors); + canvas->drawVertices(verts, SkBlendMode::kSrc, SkPaint()); +} + +DEF_TEST(Vertices_clipping, reporter) { + // A very large triangle has to be geometrically clipped (since its "fast" clipping is + // normally done in after building SkFixed coordinates). Check that we handle this. + // (and don't assert). + auto surf = SkSurface::MakeRasterN32Premul(3, 3); + + SkPoint pts[] = { { -10, 1 }, { -10, 2 }, { 1e9f, 1.5f } }; + fill_triangle(surf->getCanvas(), pts, SK_ColorBLACK); + + sk_tool_utils::PixelIter iter(surf.get()); + SkIPoint loc; + while (void* addr = iter.next(&loc)) { + SkPMColor c = *(SkPMColor*)addr; + if (loc.fY == 1) { + REPORTER_ASSERT(reporter, c == 0xFF000000); + } else { + REPORTER_ASSERT(reporter, c == 0); + } + } +} diff --git a/tools/sk_pixel_iter.h b/tools/sk_pixel_iter.h new file mode 100644 index 0000000000..8bf5a55647 --- /dev/null +++ b/tools/sk_pixel_iter.h @@ -0,0 +1,61 @@ +/* + * Copyright 2018 Google Inc. + * + * Use of this source code is governed by a BSD-style license that can be + * found in the LICENSE file. + */ + +#ifndef sk_pixel_iter_DEFINED +#define sk_pixel_iter_DEFINED + +#include "SkPixmap.h" +#include "SkSurface.h" + +namespace sk_tool_utils { + + class PixelIter { + public: + PixelIter(); + PixelIter(SkSurface* surf) { + SkPixmap pm; + if (!surf->peekPixels(&pm)) { + pm.reset(); + } + this->reset(pm); + } + + void reset(const SkPixmap& pm) { + fPM = pm; + fLoc = { -1, 0 }; + } + + void* next(SkIPoint* loc = nullptr) { + if (!fPM.addr()) { + return nullptr; + } + fLoc.fX += 1; + if (fLoc.fX >= fPM.width()) { + fLoc.fX = 0; + if (++fLoc.fY >= fPM.height()) { + this->setDone(); + return nullptr; + } + } + if (loc) { + *loc = fLoc; + } + return fPM.writable_addr(fLoc.fX, fLoc.fY); + } + + void setDone() { + fPM.reset(); + } + + private: + SkPixmap fPM; + SkIPoint fLoc; + }; + +} // namespace sk_tool_utils + +#endif // sk_tool_utils_DEFINED |