Fix bounds computation in GrAAHairlineRenderer
R=robertphillips@google.com, jvanverth@google.com
Author: bsalomon@google.com
Review URL: https://chromiumcodereview.appspot.com/23684008
git-svn-id: http://skia.googlecode.com/svn/trunk@11054 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/gm/hairlines.cpp b/gm/hairlines.cpp
index e73cc6d..7be4423 100644
--- a/gm/hairlines.cpp
+++ b/gm/hairlines.cpp
@@ -80,6 +80,30 @@
unevenClosedQuad->quadTo(SkIntToScalar(100), SkIntToScalar(100),
SkIntToScalar(75), SkIntToScalar(75));
}
+
+ // Two problem cases for gpu hairline renderer found by shapeops testing. These used
+ // to assert that the computed bounding box didn't contain all the vertices.
+ {
+ SkPath* problem1 = &fPaths.push_back();
+ problem1->moveTo(SkIntToScalar(4), SkIntToScalar(6));
+ problem1->cubicTo(SkIntToScalar(5), SkIntToScalar(6),
+ SkIntToScalar(5), SkIntToScalar(4),
+ SkIntToScalar(4), SkIntToScalar(0));
+ problem1->close();
+ }
+
+ {
+ SkPath* problem2 = &fPaths.push_back();
+ problem2->moveTo(SkIntToScalar(5), SkIntToScalar(1));
+ problem2->lineTo(SkFloatToScalar(4.32787323f), SkFloatToScalar(1.67212653f));
+ problem2->cubicTo(SkFloatToScalar(2.75223875f), SkFloatToScalar(3.24776125f),
+ SkFloatToScalar(3.00581908f), SkFloatToScalar(4.51236057f),
+ SkFloatToScalar(3.7580452f), SkFloatToScalar(4.37367964f));
+ problem2->cubicTo(SkFloatToScalar(4.66472578f), SkFloatToScalar(3.888381f),
+ SkFloatToScalar(5.f), SkFloatToScalar(2.875f),
+ SkFloatToScalar(5.f), SkFloatToScalar(1.f));
+ problem2->close();
+ }
}
virtual void onDraw(SkCanvas* canvas) SK_OVERRIDE {
diff --git a/include/core/SkRect.h b/include/core/SkRect.h
index d0eaac4..d8919ae 100644
--- a/include/core/SkRect.h
+++ b/include/core/SkRect.h
@@ -691,6 +691,21 @@
fBottom = SkMaxScalar(y, fBottom);
}
+ /** Bulk version of growToInclude */
+ void growToInclude(const SkPoint pts[], int count) {
+ this->growToInclude(pts, sizeof(SkPoint), count);
+ }
+
+ /** Bulk version of growToInclude with stride. */
+ void growToInclude(const SkPoint pts[], size_t stride, int count) {
+ SkASSERT(count >= 0);
+ SkASSERT(stride >= sizeof(SkPoint));
+ const SkPoint* end = (const SkPoint*)((intptr_t)pts + count * stride);
+ for (; pts < end; pts = (const SkPoint*)((intptr_t)pts + stride)) {
+ this->growToInclude(pts->fX, pts->fY);
+ }
+ }
+
/**
* Returns true if (p.fX,p.fY) is inside the rectangle, and the rectangle
* is not empty.
diff --git a/src/gpu/GrAAHairLinePathRenderer.cpp b/src/gpu/GrAAHairLinePathRenderer.cpp
index 60992fd..5078467 100644
--- a/src/gpu/GrAAHairLinePathRenderer.cpp
+++ b/src/gpu/GrAAHairLinePathRenderer.cpp
@@ -589,10 +589,8 @@
c1.fPos = c;
c1.fPos -= cbN;
- // This point may not be within 1 pixel of a control point. We update the bounding box to
- // include it.
intersect_lines(a0.fPos, abN, c0.fPos, cbN, &b0.fPos);
- devBounds->growToInclude(b0.fPos.fX, b0.fPos.fY);
+ devBounds->growToInclude(&verts[0].fPos, sizeof(BezierVertex), kVertsPerQuad);
if (toSrc) {
toSrc->mapPointsWithStride(&verts[0].fPos, sizeof(BezierVertex), kVertsPerQuad);
@@ -723,8 +721,6 @@
const SkMatrix& viewM = drawState->getViewMatrix();
- *devBounds = path.getBounds();
- viewM.mapRect(devBounds);
devBounds->outset(SK_Scalar1, SK_Scalar1);
int vertCnt = kVertsPerLineSeg * lineCnt;
@@ -746,10 +742,14 @@
toSrc = &ivm;
}
}
-
+ devBounds->set(lines.begin(), lines.count());
for (int i = 0; i < lineCnt; ++i) {
add_line(&lines[2*i], rtHeight, toSrc, drawState->getCoverage(), &verts);
}
+ // All the verts computed by add_line are within unit distance of the end points. Add a little
+ // extra to account for vector normalization precision.
+ static const SkScalar kOutset = SK_Scalar1 + SK_Scalar1 / 20;
+ devBounds->outset(kOutset, kOutset);
return true;
}
@@ -769,13 +769,6 @@
const SkMatrix& viewM = drawState->getViewMatrix();
- // All the vertices that we compute are within 1 of path control points with the exception of
- // one of the bounding vertices for each quad. The add_quads() function will update the bounds
- // for each quad added.
- *devBounds = path.getBounds();
- viewM.mapRect(devBounds);
- devBounds->outset(SK_Scalar1, SK_Scalar1);
-
int vertCnt = kVertsPerQuad * quadCnt + kVertsPerQuad * conicCnt;
target->drawState()->setVertexAttribs<gHairlineBezierAttribs>(SK_ARRAY_COUNT(gHairlineBezierAttribs));
@@ -798,6 +791,21 @@
}
}
+ // Seed the dev bounds with some pts known to be inside. Each quad and conic grows the bounding
+ // box to include its vertices.
+ SkPoint seedPts[2];
+ if (quadCnt) {
+ seedPts[0] = quads[0];
+ seedPts[1] = quads[2];
+ } else if (conicCnt) {
+ seedPts[0] = conics[0];
+ seedPts[1] = conics[2];
+ }
+ if (NULL != toDevice) {
+ toDevice->mapPoints(seedPts, 2);
+ }
+ devBounds->set(seedPts[0], seedPts[1]);
+
int unsubdivQuadCnt = quads.count() / 3;
for (int i = 0; i < unsubdivQuadCnt; ++i) {
SkASSERT(qSubdivs[i] >= 0);
@@ -830,7 +838,14 @@
bool check_bounds(GrDrawState* drawState, const SkRect& devBounds, void* vertices, int vCount)
{
SkRect tolDevBounds = devBounds;
- tolDevBounds.outset(SK_Scalar1 / 10000, SK_Scalar1 / 10000);
+ // The bounds ought to be tight, but in perspective the below code runs the verts
+ // through the view matrix to get back to dev coords, which can introduce imprecision.
+ if (drawState->getViewMatrix().hasPerspective()) {
+ tolDevBounds.outset(SK_Scalar1 / 1000, SK_Scalar1 / 1000);
+ } else {
+ // Non-persp matrices cause this path renderer to draw in device space.
+ SkASSERT(drawState->getViewMatrix().isIdentity());
+ }
SkRect actualBounds;
VertexType* verts = reinterpret_cast<VertexType*>(vertices);
@@ -880,7 +895,7 @@
conicCnt = conics.count() / 3;
// do lines first
- {
+ if (lineCnt) {
GrDrawTarget::AutoReleaseGeometry arg;
SkRect devBounds;
@@ -926,7 +941,7 @@
}
// then quadratics/conics
- {
+ if (quadCnt || conicCnt) {
GrDrawTarget::AutoReleaseGeometry arg;
SkRect devBounds;