Add GPU support for axis-aligned ovals:
- Add drawOval base function to SkDevice, and override in SkGpuDevice
- Move isSimilarityMatrix to SkMatrix (renamed to isSimilarity) and fixed up unit test
- Since both SkGpuDevice::drawOval() and GrContext::drawPath() can try to draw ovals, added GrContext::canDrawOval() and GrContext::internalDrawOval() to avoid duplicate code
- Hooked in axis-aligned oval fill shader
- Enabled GPU stroked circles
- Added stroked circle bench test
Review URL: https://codereview.appspot.com/7137050
git-svn-id: http://skia.googlecode.com/svn/trunk@7304 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/GrContext.cpp b/src/gpu/GrContext.cpp
index 43dda9c..9739199 100644
--- a/src/gpu/GrContext.cpp
+++ b/src/gpu/GrContext.cpp
@@ -935,59 +935,62 @@
SkScalar fInnerRadius;
};
-/* Returns true if will map a circle to another circle. This can be true
- * if the matrix only includes square-scale, rotation, translation.
- */
-inline bool isSimilarityTransformation(const SkMatrix& matrix,
- SkScalar tol = SK_ScalarNearlyZero) {
- if (matrix.isIdentity() || matrix.getType() == SkMatrix::kTranslate_Mask) {
- return true;
- }
- if (matrix.hasPerspective()) {
- return false;
- }
-
- SkScalar mx = matrix.get(SkMatrix::kMScaleX);
- SkScalar sx = matrix.get(SkMatrix::kMSkewX);
- SkScalar my = matrix.get(SkMatrix::kMScaleY);
- SkScalar sy = matrix.get(SkMatrix::kMSkewY);
-
- if (mx == 0 && sx == 0 && my == 0 && sy == 0) {
- return false;
- }
-
- // it has scales or skews, but it could also be rotation, check it out.
- SkVector vec[2];
- vec[0].set(mx, sx);
- vec[1].set(sy, my);
-
- return SkScalarNearlyZero(vec[0].dot(vec[1]), SkScalarSquare(tol)) &&
- SkScalarNearlyEqual(vec[0].lengthSqd(), vec[1].lengthSqd(),
- SkScalarSquare(tol));
+inline bool circleStaysCircle(const SkMatrix& m) {
+ return m.isSimilarity();
}
}
-// TODO: strokeWidth can't be larger than zero right now.
-// It will be fixed when drawPath() can handle strokes.
void GrContext::drawOval(const GrPaint& paint,
- const GrRect& rect,
- SkScalar strokeWidth) {
- GrAssert(strokeWidth <= 0);
- if (!isSimilarityTransformation(this->getMatrix()) ||
- !paint.isAntiAlias() ||
- rect.height() != rect.width()) {
+ const GrRect& oval,
+ const SkStrokeRec& stroke) {
+
+ if (!canDrawOval(paint, oval, stroke)) {
SkPath path;
- path.addOval(rect);
- path.setFillType(SkPath::kWinding_FillType);
- SkStrokeRec stroke(0 == strokeWidth ? SkStrokeRec::kHairline_InitStyle :
- SkStrokeRec::kFill_InitStyle);
- if (strokeWidth > 0) {
- stroke.setStrokeStyle(strokeWidth, true);
- }
- this->internalDrawPath(paint, path, stroke);
+ path.addOval(oval);
+ this->drawPath(paint, path, stroke);
return;
+ }
+
+ internalDrawOval(paint, oval, stroke);
+}
+
+bool GrContext::canDrawOval(const GrPaint& paint, const GrRect& oval, const SkStrokeRec& stroke) const {
+
+ if (!paint.isAntiAlias()) {
+ return false;
}
+
+ // we can draw circles in any style
+ bool isCircle = SkScalarNearlyEqual(oval.width(), oval.height())
+ && circleStaysCircle(this->getMatrix());
+ // and for now, axis-aligned ellipses only with fill or stroke-and-fill
+ SkStrokeRec::Style style = stroke.getStyle();
+ bool isStroke = (style == SkStrokeRec::kStroke_Style || style == SkStrokeRec::kHairline_Style);
+ bool isFilledAxisAlignedEllipse = this->getMatrix().rectStaysRect() && !isStroke;
+
+ return isCircle || isFilledAxisAlignedEllipse;
+}
+
+void GrContext::internalDrawOval(const GrPaint& paint,
+ const GrRect& oval,
+ const SkStrokeRec& stroke) {
+
+ SkScalar xRadius = SkScalarHalf(oval.width());
+ SkScalar yRadius = SkScalarHalf(oval.height());
+
+ SkScalar strokeWidth = stroke.getWidth();
+ SkStrokeRec::Style style = stroke.getStyle();
+
+ bool isCircle = SkScalarNearlyEqual(xRadius, yRadius) && circleStaysCircle(this->getMatrix());
+#ifdef SK_DEBUG
+ {
+ // we should have checked for this previously
+ bool isStroke = (style == SkStrokeRec::kStroke_Style || style == SkStrokeRec::kHairline_Style);
+ bool isFilledAxisAlignedEllipse = this->getMatrix().rectStaysRect() && !isStroke;
+ SkASSERT(paint.isAntiAlias() && (isCircle || isFilledAxisAlignedEllipse));
+ }
+#endif
GrDrawTarget* target = this->prepareToDraw(&paint, DEFAULT_BUFFERING);
@@ -1008,22 +1011,6 @@
GrVertexLayout layout = GrDrawTarget::kEdge_VertexLayoutBit;
GrAssert(sizeof(CircleVertex) == GrDrawTarget::VertexSize(layout));
- GrPoint center = GrPoint::Make(rect.centerX(), rect.centerY());
- SkScalar radius = SkScalarHalf(rect.width());
-
- vm.mapPoints(¢er, 1);
- radius = vm.mapRadius(radius);
-
- SkScalar outerRadius = radius;
- SkScalar innerRadius = 0;
- SkScalar halfWidth = 0;
- if (strokeWidth == 0) {
- halfWidth = SkScalarHalf(SK_Scalar1);
-
- outerRadius += halfWidth;
- innerRadius = SkMaxScalar(0, radius - halfWidth);
- }
-
GrDrawTarget::AutoReleaseGeometry geo(target, layout, 4, 0);
if (!geo.succeeded()) {
GrPrintf("Failed to get space for vertices!\n");
@@ -1032,26 +1019,93 @@
CircleVertex* verts = reinterpret_cast<CircleVertex*>(geo.vertices());
+ GrPoint center = GrPoint::Make(oval.centerX(), oval.centerY());
+ vm.mapPoints(¢er, 1);
+
+ SkScalar L;
+ SkScalar R;
+ SkScalar T;
+ SkScalar B;
+
+ if (isCircle) {
+ drawState->setVertexEdgeType(GrDrawState::kCircle_EdgeType);
+
+ xRadius = vm.mapRadius(xRadius);
+
+ SkScalar outerRadius = xRadius;
+ SkScalar innerRadius = 0;
+ SkScalar halfWidth = 0;
+ if (style != SkStrokeRec::kFill_Style) {
+ strokeWidth = vm.mapRadius(strokeWidth);
+ if (SkScalarNearlyZero(strokeWidth)) {
+ halfWidth = SK_ScalarHalf;
+ } else {
+ halfWidth = SkScalarHalf(strokeWidth);
+ }
+
+ outerRadius += halfWidth;
+ if (style == SkStrokeRec::kStroke_Style || style == SkStrokeRec::kHairline_Style) {
+ innerRadius = SkMaxScalar(0, xRadius - halfWidth);
+ }
+ }
+
+ for (int i = 0; i < 4; ++i) {
+ verts[i].fCenter = center;
+ verts[i].fOuterRadius = outerRadius;
+ verts[i].fInnerRadius = innerRadius;
+ }
+
+ L = -outerRadius;
+ R = +outerRadius;
+ T = -outerRadius;
+ B = +outerRadius;
+ } else { // is axis-aligned ellipse
+ drawState->setVertexEdgeType(GrDrawState::kEllipse_EdgeType);
+
+ SkRect xformedRect;
+ vm.mapRect(&xformedRect, oval);
+
+ xRadius = SkScalarHalf(xformedRect.width());
+ yRadius = SkScalarHalf(xformedRect.height());
+
+ if (style == SkStrokeRec::kStrokeAndFill_Style && strokeWidth > 0.0f) {
+ SkScalar halfWidth = SkScalarHalf(strokeWidth);
+ // do (potentially) anisotropic mapping
+ SkVector scaledStroke;
+ scaledStroke.set(halfWidth, halfWidth);
+ vm.mapVectors(&scaledStroke, 1);
+ // this is legit only if scale & translation (which should be the case at the moment)
+ xRadius += scaledStroke.fX;
+ yRadius += scaledStroke.fY;
+ }
+
+ SkScalar ratio = SkScalarDiv(xRadius, yRadius);
+
+ for (int i = 0; i < 4; ++i) {
+ verts[i].fCenter = center;
+ verts[i].fOuterRadius = xRadius;
+ verts[i].fInnerRadius = ratio;
+ }
+
+ L = -xRadius;
+ R = +xRadius;
+ T = -yRadius;
+ B = +yRadius;
+ }
+
// The fragment shader will extend the radius out half a pixel
// to antialias. Expand the drawn rect here so all the pixels
// will be captured.
- SkScalar L = center.fX - outerRadius - SkFloatToScalar(0.5f);
- SkScalar R = center.fX + outerRadius + SkFloatToScalar(0.5f);
- SkScalar T = center.fY - outerRadius - SkFloatToScalar(0.5f);
- SkScalar B = center.fY + outerRadius + SkFloatToScalar(0.5f);
+ L += center.fX - SK_ScalarHalf;
+ R += center.fX + SK_ScalarHalf;
+ T += center.fY - SK_ScalarHalf;
+ B += center.fY + SK_ScalarHalf;
verts[0].fPos = SkPoint::Make(L, T);
verts[1].fPos = SkPoint::Make(R, T);
verts[2].fPos = SkPoint::Make(L, B);
verts[3].fPos = SkPoint::Make(R, B);
- for (int i = 0; i < 4; ++i) {
- verts[i].fCenter = center;
- verts[i].fOuterRadius = outerRadius;
- verts[i].fInnerRadius = innerRadius;
- }
-
- drawState->setVertexEdgeType(GrDrawState::kCircle_EdgeType);
target->drawNonIndexed(kTriangleStrip_GrPrimitiveType, 0, 4);
}
@@ -1065,10 +1119,10 @@
}
SkRect ovalRect;
- if ((stroke.isHairlineStyle() || stroke.isFillStyle()) && !path.isInverseFillType() &&
- path.isOval(&ovalRect)) {
- SkScalar width = stroke.isHairlineStyle() ? 0 : -SK_Scalar1;
- this->drawOval(paint, ovalRect, width);
+ bool isOval = path.isOval(&ovalRect);
+
+ if (isOval && !path.isInverseFillType() && this->canDrawOval(paint, ovalRect, stroke)) {
+ this->drawOval(paint, ovalRect, stroke);
return;
}