void updateDom() {
const SkPoint corner = pos - SkPoint::Make(size.width() / 2, size.height() / 2);
objectNode->setX(SkSVGLength(corner.x()));
objectNode->setY(SkSVGLength(corner.y()));
// Simulate parallax shadow for a centered light source.
SkPoint shadowOffset = pos - SkPoint::Make(kBounds.centerX(), kBounds.centerY());
shadowOffset.scale(kShadowParallax);
const SkPoint shadowCorner = corner + shadowOffset;
shadowNode->setX(SkSVGLength(shadowCorner.x()));
shadowNode->setY(SkSVGLength(shadowCorner.y()));
}
// https://www.w3.org/TR/SVG/types.html#DataTypeLength
bool SkSVGAttributeParser::parseLength(SkSVGLength* length) {
SkScalar s;
SkSVGLength::Unit u = SkSVGLength::Unit::kNumber;
if (this->parseScalarToken(&s) &&
(this->parseLengthUnitToken(&u) || this->parseSepToken() || this->parseEOSToken())) {
*length = SkSVGLength(s, u);
// consume trailing separators
this->parseSepToken();
return true;
}
return false;
}
SkSVGPresentationAttributes SkSVGPresentationAttributes::MakeInitial() {
SkSVGPresentationAttributes result;
result.fFill.set(SkSVGPaint(SkSVGColorType(SK_ColorBLACK)));
result.fFillOpacity.set(SkSVGNumberType(1));
result.fStroke.set(SkSVGPaint(SkSVGPaint::Type::kNone));
result.fStrokeLineCap.set(SkSVGLineCap(SkSVGLineCap::Type::kButt));
result.fStrokeLineJoin.set(SkSVGLineJoin(SkSVGLineJoin::Type::kMiter));
result.fStrokeOpacity.set(SkSVGNumberType(1));
result.fStrokeWidth.set(SkSVGLength(1));
return result;
}
void onOnceBeforeDraw() override {
const SkRect fieldBounds = kBounds.makeOutset(kBallSize / 2, kBallSize / 2);
const SkRRect ball = SkRRect::MakeOval(SkRect::MakeWH(kBallSize, kBallSize));
const SkRRect paddle = SkRRect::MakeRectXY(SkRect::MakeWH(kPaddleSize.width(),
kPaddleSize.height()),
kPaddleSize.width() / 2,
kPaddleSize.width() / 2);
fBall.initialize(ball,
SK_ColorGREEN,
SkPoint::Make(kBounds.centerX(), kBounds.centerY()),
SkVector::Make(fRand.nextRangeScalar(kBallSpeedMin, kBallSpeedMax),
fRand.nextRangeScalar(kBallSpeedMin, kBallSpeedMax)));
fPaddle0.initialize(paddle,
SK_ColorBLUE,
SkPoint::Make(fieldBounds.left() - kPaddleSize.width() / 2,
fieldBounds.centerY()),
SkVector::Make(0, 0));
fPaddle1.initialize(paddle,
SK_ColorRED,
SkPoint::Make(fieldBounds.right() + kPaddleSize.width() / 2,
fieldBounds.centerY()),
SkVector::Make(0, 0));
// Background decoration.
SkPath bgPath;
bgPath.moveTo(kBounds.left() , fieldBounds.top());
bgPath.lineTo(kBounds.right(), fieldBounds.top());
bgPath.moveTo(kBounds.left() , fieldBounds.bottom());
bgPath.lineTo(kBounds.right(), fieldBounds.bottom());
// TODO: stroke-dash support would come in handy right about now.
for (uint32_t i = 0; i < kBackgroundDashCount; ++i) {
bgPath.moveTo(kBounds.centerX(),
kBounds.top() + (i + 0.25f) * kBounds.height() / kBackgroundDashCount);
bgPath.lineTo(kBounds.centerX(),
kBounds.top() + (i + 0.75f) * kBounds.height() / kBackgroundDashCount);
}
sk_sp<SkSVGPath> bg = SkSVGPath::Make();
bg->setPath(bgPath);
bg->setFill(SkSVGPaint(SkSVGPaint::Type::kNone));
bg->setStroke(SkSVGPaint(SkSVGColorType(SK_ColorBLACK)));
bg->setStrokeWidth(SkSVGLength(kBackgroundStroke));
// Build the SVG DOM tree.
sk_sp<SkSVGSVG> root = SkSVGSVG::Make();
root->appendChild(std::move(bg));
root->appendChild(fPaddle0.shadowNode);
root->appendChild(fPaddle1.shadowNode);
root->appendChild(fBall.shadowNode);
root->appendChild(fPaddle0.objectNode);
root->appendChild(fPaddle1.objectNode);
root->appendChild(fBall.objectNode);
// Handle everything in a normalized 1x1 space.
root->setViewBox(SkSVGViewBoxType(SkRect::MakeWH(1, 1)));
fDom = sk_sp<SkSVGDOM>(new SkSVGDOM());
fDom->setContainerSize(SkSize::Make(this->width(), this->height()));
fDom->setRoot(std::move(root));
// Off we go.
this->updatePaddleStrategy();
}
