Added animation to pie chart while changing its parts.

Telegram/SourceFiles/statistics/point_details_widget.cpp

@@ -279,7 +279,7 @@ void PointDetailsWidget::setXIndex(int xIndex) {
 	_lines.reserve(_chartData.lines.size());
 	auto hasPositiveValues = false;
 	const auto parts = _maxPercentageWidth
-		? PiePartsPercentage(
+		? PiePartsPercentageByIndices(
 			_chartData,
 			nullptr,
 			{ float64(xIndex), float64(xIndex) }).parts

Telegram/SourceFiles/statistics/view/stack_linear_chart_common.cpp

@@ -14,25 +14,11 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 namespace Statistic {
 
 PiePartData PiePartsPercentage(
-		const Data::StatisticalChart &chartData,
+		const std::vector<float64> &sums,
-		const std::shared_ptr<LinesFilterController> &linesFilter,
+		float64 totalSum,
-		const Limits &xIndices) {
+		bool round) {
 	auto result = PiePartData();
-	result.parts.reserve(chartData.lines.size());
+	result.parts.reserve(sums.size());
-	auto sums = std::vector<float64>();
-	sums.reserve(chartData.lines.size());
-	auto totalSum = 0.;
-	for (const auto &line : chartData.lines) {
-		auto sum = 0;
-		for (auto i = xIndices.min; i <= xIndices.max; i++) {
-			sum += line.y[i];
-		}
-		if (linesFilter) {
-			sum *= linesFilter->alpha(line.id);
-		}
-		totalSum += sum;
-		sums.push_back(sum);
-	}
 	auto stackedPercentage = 0.;
 
 	auto sumPercDiffs = 0.;
@@ -46,7 +32,9 @@ PiePartData PiePartsPercentage(
 	constexpr auto kPerChar = '%';
 	for (auto k = 0; k < sums.size(); k++) {
 		const auto rawPercentage = totalSum ? (sums[k] / totalSum) : 0.;
-		const auto rounded = 0.01 * std::round(rawPercentage * 100.);
+		const auto rounded = round
+			? (0.01 * std::round(rawPercentage * 100.))
+			: rawPercentage;
 		roundedPercentagesSum += rounded;
 		const auto diff = rawPercentage - rounded;
 		sumPercDiffs += diff;
@@ -68,7 +56,7 @@ PiePartData PiePartsPercentage(
 		});
 		result.pieHasSinglePart |= (rounded == 1.);
 	}
-	{
+	if (round) {
 		const auto index = (roundedPercentagesSum > 1.)
 			? maxPercDiffIndex
 			: minPercDiffIndex;
@@ -85,4 +73,25 @@ PiePartData PiePartsPercentage(
 	return result;
 }
 
+PiePartData PiePartsPercentageByIndices(
+		const Data::StatisticalChart &chartData,
+		const std::shared_ptr<LinesFilterController> &linesFilter,
+		const Limits &xIndices) {
+	auto sums = std::vector<float64>();
+	sums.reserve(chartData.lines.size());
+	auto totalSum = 0.;
+	for (const auto &line : chartData.lines) {
+		auto sum = 0;
+		for (auto i = xIndices.min; i <= xIndices.max; i++) {
+			sum += line.y[i];
+		}
+		if (linesFilter) {
+			sum *= linesFilter->alpha(line.id);
+		}
+		totalSum += sum;
+		sums.push_back(sum);
+	}
+	return PiePartsPercentage(sums, totalSum, true);
+}
+
 } // namespace Statistic

Telegram/SourceFiles/statistics/view/stack_linear_chart_common.h

@@ -27,6 +27,11 @@ struct PiePartData final {
 };
 
 [[nodiscard]] PiePartData PiePartsPercentage(
+	const std::vector<float64> &sums,
+	float64 totalSum,
+	bool round);
+
+[[nodiscard]] PiePartData PiePartsPercentageByIndices(
 	const Data::StatisticalChart &chartData,
 	const std::shared_ptr<LinesFilterController> &linesFilter,
 	const Limits &xIndices);

Telegram/SourceFiles/statistics/view/stack_linear_chart_view.cpp

@@ -87,6 +87,57 @@ inline float64 InterpolationRatio(float64 from, float64 to, float64 result) {
 
 } // namespace
 
+void StackLinearChartView::ChangingPiePartController::setParts(
+		const std::vector<PiePartData::Part> &was,
+		const std::vector<PiePartData::Part> &now) {
+	if (_animValues.size() != was.size()) {
+		_animValues = std::vector<anim::value>(was.size(), anim::value());
+		for (auto i = 0; i < was.size(); i++) {
+			_animValues[i] = anim::value(
+				was[i].roundedPercentage,
+				now[i].roundedPercentage);
+		}
+	} else {
+		for (auto i = 0; i < was.size(); i++) {
+			_animValues[i] = anim::value(
+				_animValues[i].current(),
+				now[i].roundedPercentage);
+		}
+	}
+	_startedAt = crl::now();
+	_isFinished = false;
+}
+
+void StackLinearChartView::ChangingPiePartController::update() {
+	const auto progress = std::clamp(
+		(crl::now() - _startedAt) / float64(st::slideWrapDuration),
+		0.,
+		1.);
+	auto totalSum = 0.;
+	auto finished = true;
+	auto result = std::vector<float64>();
+	result.reserve(_animValues.size());
+	for (auto &anim : _animValues) {
+		anim.update(progress, anim::easeOutCubic);
+		if (finished && (anim.current() != anim.to())) {
+			finished = false;
+		}
+		const auto value = anim.current();
+		result.push_back(value);
+		totalSum += value;
+	}
+	_isFinished = finished;
+	_current = PiePartsPercentage(result, totalSum, false);
+}
+
+PiePartData StackLinearChartView::ChangingPiePartController::current() const {
+	return _current;
+}
+
+bool StackLinearChartView::ChangingPiePartController::isFinished() const {
+	return _isFinished;
+}
+
 StackLinearChartView::StackLinearChartView() {
 	_piePartAnimation.init([=] { AbstractChartView::update(); });
 }
@@ -185,7 +236,7 @@ void StackLinearChartView::saveZoomRange(const PaintContext &c) {
 }
 
 void StackLinearChartView::savePieTextParts(const PaintContext &c) {
-	auto data = PiePartsPercentage(
+	auto data = PiePartsPercentageByIndices(
 		c.chartData,
 		linesFilterController(),
 		_transition.zoomedInRangeXIndices);
@@ -504,14 +555,33 @@ void StackLinearChartView::paintZoomed(QPainter &p, const PaintContext &c) {
 		return;
 	}
 
+	const auto wasZoomedInRangeXIndices = _transition.zoomedInRangeXIndices;
 	saveZoomRange(c);
-	const auto partsData = PiePartsPercentage(
+	const auto &[zoomedStart, zoomedEnd] = _transition.zoomedInRangeXIndices;
+	const auto partsData = PiePartsPercentageByIndices(
 		c.chartData,
 		linesFilterController(),
 		_transition.zoomedInRangeXIndices);
+	const auto xIndicesChanged = (wasZoomedInRangeXIndices.min != zoomedStart)
+		|| (wasZoomedInRangeXIndices.max != zoomedEnd);
+	if (xIndicesChanged) {
+		const auto wasParts = PiePartsPercentageByIndices(
+			c.chartData,
+			linesFilterController(),
+			wasZoomedInRangeXIndices);
+		_changingPieController.setParts(wasParts.parts, partsData.parts);
+		if (!_piePartAnimation.animating()) {
+			_piePartAnimation.start();
+		}
+	}
+	if (!_changingPieController.isFinished()) {
+		_changingPieController.update();
+	}
 	_pieHasSinglePart = partsData.pieHasSinglePart;
-	const auto &parts = partsData.parts;
+	applyParts(partsData.parts);
-	applyParts(parts);
+	const auto &parts = _changingPieController.isFinished()
+		? partsData.parts
+		: _changingPieController.current().parts;
 
 	p.fillRect(c.rect + QMargins(0, 0, 0, st::lineWidth), st::boxBg);
 	const auto center = QPointF(c.rect.center());
@@ -547,14 +617,12 @@ void StackLinearChartView::paintZoomed(QPainter &p, const PaintContext &c) {
 			selectedLineIndex = k;
 		}
 	}
-	if (_piePartController.isFinished()) {
+	if (_piePartController.isFinished() && _changingPieController.isFinished()) {
 		_piePartAnimation.stop();
 	}
 	paintPieText(p, c);
 
 	if (selectedLineIndex >= 0) {
-		const auto &[zoomedStart, zoomedEnd] =
-			_transition.zoomedInRangeXIndices;
 		const auto &line = c.chartData.lines[selectedLineIndex];
 		auto sum = 0;
 		for (auto i = zoomedStart; i <= zoomedEnd; i++) {
@@ -633,11 +701,13 @@ void StackLinearChartView::paintZoomedFooter(
 }
 
 void StackLinearChartView::paintPieText(QPainter &p, const PaintContext &c) {
-	constexpr auto kMinPercentage = 0.03;
+	constexpr auto kMinPercentage = 0.039;
 	if (_transition.progress == 1.) {
 		savePieTextParts(c);
 	}
-	const auto &parts = _transition.textParts;
+	const auto &parts = _changingPieController.isFinished()
+		? _transition.textParts
+		: _changingPieController.current().parts;
 
 	const auto center = QPointF(c.rect.center());
 	const auto side = (c.rect.width() / 2.) * kCircleSizeRatio;

Telegram/SourceFiles/statistics/view/stack_linear_chart_view.h

@@ -121,8 +121,28 @@ private:
 		LineId _selected = -1;
 
 	};
+
+	class ChangingPiePartController final {
+	public:
+		void setParts(
+			const std::vector<PiePartData::Part> &was,
+			const std::vector<PiePartData::Part> &now);
+		void update();
+		[[nodiscard]] PiePartData current() const;
+		[[nodiscard]] bool isFinished() const;
+
+	private:
+		crl::time _startedAt = 0;;
+		std::vector<anim::value> _animValues;
+		PiePartData _current;
+		bool _isFinished = true;
+
+	};
+
 	PiePartController _piePartController;
+	ChangingPiePartController _changingPieController;
 	Ui::Animations::Basic _piePartAnimation;
+
 	bool _pieHasSinglePart = false;
 
 };