AuroraMiddleware/skia2
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

GrTessellator: fix for points which become non-finite on AA stroking.

Browse Source 
If input points are near-infinite, they may become inf or NaN when
stroked.  Before converting the results of intersection from double
to float, clamp them to the [-FLT_MAX/FLT_MAX] range.

BUG=798679

Change-Id: I7d61130dd26147a9b7cfd38aa96567e3867b5c3e
Reviewed-on: https://skia-review.googlesource.com/90983
Commit-Queue: Stephen White <senorblanco@chromium.org>
Reviewed-by: Brian Osman <brianosman@google.com>
This commit is contained in:
Stephen White 2018-01-04 14:01:10 -05:00 committed by Skia Commit-Bot
parent 7397d7ade8
commit 94b7e54256
2 changed files with 20 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
src/gpu/GrTessellator.cpp
View File

@ -16,6 +16,7 @@
#include "SkPointPriv.h"
#include "SkTDPQueue.h"
#include <algorithm>
#include <stdio.h>
/*
@ -282,6 +283,10 @@ inline void round(SkPoint* p) {
p->fY = SkScalarRoundToScalar(p->fY * SkFloatToScalar(4.0f)) * SkFloatToScalar(0.25f);
}
inline SkScalar double_to_clamped_scalar(double d) {
return SkDoubleToScalar(std::min((double) SK_ScalarMax, std::max(d, (double) -SK_ScalarMax)));
}
// A line equation in implicit form. fA * x + fB * y + fC = 0, for all points (x, y) on the line.
struct Line {
Line(double a, double b, double c) : fA(a), fB(b), fC(c) {}
@ -320,9 +325,9 @@ struct Line {
if (denom == 0.0) {
return false;
}
double scale = 1.0f / denom;
point->fX = SkDoubleToScalar((fB * other.fC - other.fB * fC) * scale);
point->fY = SkDoubleToScalar((other.fA * fC - fA * other.fC) * scale);
double scale = 1.0 / denom;
point->fX = double_to_clamped_scalar((fB * other.fC - other.fB * fC) * scale);
point->fY = double_to_clamped_scalar((other.fA * fC - fA * other.fC) * scale);
round(point);
return true;
}

12
tests/TessellatingPathRendererTests.cpp
View File

@ -406,6 +406,17 @@ static SkPath create_path_26() {
return path;
}
// A path which results in non-finite points when stroked and bevelled for AA.
static SkPath create_path_27() {
SkPath path;
path.moveTo(8.5027233009104409507e+37, 1.7503381025241130639e+37);
path.lineTo(7.0923661737711584874e+37, 1.4600074517285415699e+37);
path.lineTo(7.0848733446033294691e+37, 1.4584649744781838604e+37);
path.lineTo(-2.0473916115129349496e+37, -4.2146796450364162012e+36);
path.lineTo(2.0473912312177548811e+37, 4.2146815465123165435e+36);
return path;
}
static std::unique_ptr<GrFragmentProcessor> create_linear_gradient_processor(GrContext* ctx) {
SkPoint pts[2] = { {0, 0}, {1, 1} };
@ -495,5 +506,6 @@ DEF_GPUTEST_FOR_ALL_CONTEXTS(TessellatingPathRendererTests, reporter, ctxInfo) {
test_path(ctx, rtc.get(), create_path_24());
test_path(ctx, rtc.get(), create_path_25(), SkMatrix(), GrAAType::kCoverage);
test_path(ctx, rtc.get(), create_path_26(), SkMatrix(), GrAAType::kCoverage);
test_path(ctx, rtc.get(), create_path_27(), SkMatrix(), GrAAType::kCoverage);
}
#endif