skia2/fuzz/FuzzPolyUtils.cpp
Jim Van Verth 62bb436301 Limit offset range when fuzzing SkOffsetSimplePolygon
Bug: oss-fuzz:43699
Change-Id: Ie856aed03b513a4ea84a09deda6a05b95b086b07
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/496876
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
Commit-Queue: Jim Van Verth <jvanverth@google.com>
2022-01-20 21:03:51 +00:00

60 lines
1.8 KiB
C++

/*
* Copyright 2018 Google LLC
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "fuzz/Fuzz.h"
#include "include/private/SkTemplates.h"
#include "src/utils/SkPolyUtils.h"
void inline ignoreResult(bool ) {}
// clamps the point to the nearest 16th of a pixel
static SkPoint sanitize_point(const SkPoint& in) {
SkPoint out;
out.fX = SkScalarRoundToScalar(16.f*in.fX)*0.0625f;
out.fY = SkScalarRoundToScalar(16.f*in.fY)*0.0625f;
return out;
}
DEF_FUZZ(PolyUtils, fuzz) {
int count;
fuzz->nextRange(&count, 0, 512);
SkAutoSTMalloc<64, SkPoint> polygon(count);
for (int index = 0; index < count; ++index) {
fuzz->next(&polygon[index].fX, &polygon[index].fY);
polygon[index] = sanitize_point(polygon[index]);
}
SkRect bounds;
bounds.setBoundsCheck(polygon, count);
ignoreResult(SkGetPolygonWinding(polygon, count));
bool isConvex = SkIsConvexPolygon(polygon, count);
bool isSimple = SkIsSimplePolygon(polygon, count);
SkTDArray<SkPoint> output;
if (isConvex) {
SkScalar inset;
fuzz->next(&inset);
ignoreResult(SkInsetConvexPolygon(polygon, count, inset, &output));
}
if (isSimple) {
SkScalar offset;
// Limit this to prevent timeouts.
// This should be fine, as this is roughly the range we expect from the shadow algorithm.
fuzz->nextRange(&offset, -1000, 1000);
ignoreResult(SkOffsetSimplePolygon(polygon, count, bounds, offset, &output));
SkAutoSTMalloc<64, uint16_t> indexMap(count);
for (int index = 0; index < count; ++index) {
fuzz->next(&indexMap[index]);
}
SkTDArray<uint16_t> outputIndices;
ignoreResult(SkTriangulateSimplePolygon(polygon, indexMap, count, &outputIndices));
}
}