Add marker top position to draw event

Author: schaumb

CHANGELOG.md

@@ -14,6 +14,9 @@
 
 - Changed MarkerId to be a string instead of a number.
 
+### Added
+
+- Add marker top position to draw event
 
 ## [0.14.0] - 2024-10-03
 

src/apps/weblib/ts-api/events.ts

@@ -137,11 +137,18 @@ export interface Logo extends Element {
 export interface Area extends Element {
 	tagName: 'plot-area'
 }
+
+/** Marker element position structure helper for tooltip */
+export interface MarkerPosition {
+	top: Point
+}
+
 /** Plot marker element of the chart representing a data point. */
 export interface Marker extends Element {
 	tagName: 'plot-marker'
 	categories: Data.Record
 	values: Data.Record
+	position: MarkerPosition
 	/** Unique index of the marker. */
 	index: string
 }

src/chart/main/events.h

@@ -247,16 +247,22 @@ class Events
 		struct Marker : Element
 		{
 			const Gen::Marker ▮
+			struct DataPosition
+			{
+				Geom::Point top;
+			} position;
 
-			explicit Marker(const Gen::Marker &marker) :
+			explicit Marker(const Gen::Marker &marker,
+			    const DataPosition &position) :
 			    Element("plot-marker"),
-			    marker(marker)
+			    marker(marker),
+			    position(position)
 			{}
 
 			void appendToJSON(Conv::JSONObj &&jsonObj) const override
 			{
-				Element::appendToJSON(
-				    marker.appendToJSON(std::move(jsonObj)));
+				Element::appendToJSON(marker.appendToJSON(
+				    std::move(jsonObj))("position", position));
 			}
 		};
 
@@ -268,8 +274,10 @@ class Events
 		{
 			bool horizontal;
 
-			MarkerGuide(const Gen::Marker &marker, bool horizontal) :
-			    MarkerChild("guide", marker),
+			MarkerGuide(const Gen::Marker &marker,
+			    const Marker::DataPosition &position,
+			    bool horizontal) :
+			    MarkerChild("guide", marker, position),
 			    horizontal(horizontal)
 			{}
 
@@ -313,15 +321,19 @@ class Events
 			return std::make_unique<Legend>(properties);
 		}
 
-		static auto marker(const Gen::Marker &marker)
+		static auto marker(const Gen::Marker &marker,
+		    const Marker::DataPosition &position)
 		{
-			return std::make_unique<Marker>(marker);
+			return std::make_unique<Marker>(marker, position);
 		}
 
 		static auto markerGuide(const Gen::Marker &marker,
+		    const Marker::DataPosition &position,
 		    bool horizontal)
 		{
-			return std::make_unique<MarkerGuide>(marker, horizontal);
+			return std::make_unique<MarkerGuide>(marker,
+			    position,
+			    horizontal);
 		}
 
 		static auto root()
@@ -362,11 +374,13 @@ class Events
 		}
 
 		static auto markerLabel(const std::string &label,
-		    const Gen::Marker &marker)
+		    const Gen::Marker &marker,
+		    const Marker::DataPosition &position)
 		{
 			return std::make_unique<Text<MarkerChild>>(label,
 			    "label",
-			    marker);
+			    marker,
+			    position);
 		}
 
 		static auto dimLegendLabel(

src/chart/rendering/markerrenderer.cpp

@@ -67,7 +67,9 @@ void MarkerRenderer::drawLines(Gfx::ICanvas &canvas,
 			const Geom::Line line(axisPoint, blended.center);
 
 			auto guideElement =
-			    Events::Targets::markerGuide(blended.marker, false);
+			    Events::Targets::markerGuide(blended.marker,
+			        blended.dataPosition,
+			        false);
 
 			if (rootEvents.draw.plot.marker.guide->invoke(
 			        Events::OnLineDrawEvent(*guideElement,
@@ -88,7 +90,9 @@ void MarkerRenderer::drawLines(Gfx::ICanvas &canvas,
 			const Geom::Line line(center, axisPoint);
 
 			auto guideElement =
-			    Events::Targets::markerGuide(blended.marker, true);
+			    Events::Targets::markerGuide(blended.marker,
+			        blended.dataPosition,
+			        true);
 
 			if (rootEvents.draw.plot.marker.guide->invoke(
 			        Events::OnLineDrawEvent(*guideElement,
@@ -262,7 +266,8 @@ void MarkerRenderer::draw(Gfx::ICanvas &canvas,
 	canvas.setLineWidth(*rootStyle.plot.marker.borderWidth);
 
 	auto markerElement =
-	    Events::Targets::marker(abstractMarker.marker);
+	    Events::Targets::marker(abstractMarker.marker,
+	        abstractMarker.dataPosition);
 
 	auto colorAlpha =
 	    Math::FuzzyBool::And<double>(abstractMarker.enabled, factor);
@@ -363,7 +368,9 @@ void MarkerRenderer::drawLabel(Gfx::ICanvas &canvas,
 	    Gfx::ColorTransform::OverrideColor(
 	        (*labelStyle.filter)(color)*colorAlpha),
 	    *rootEvents.draw.plot.marker.label,
-	    Events::Targets::markerLabel(text, marker));
+	    Events::Targets::markerLabel(text,
+	        marker,
+	        abstractMarker.dataPosition));
 }
 
 std::string MarkerRenderer::getLabelText(

src/chart/rendering/markers/abstractmarker.cpp

@@ -47,6 +47,7 @@ AbstractMarker AbstractMarker::create(const DrawingContext &ctx,
 	switch (shapeType) {
 	case Gen::ShapeType::rectangle:
 		return RectangleMarker(marker,
+		    ctx.coordSys,
 		    ctx.getOptions(),
 		    ctx.rootStyle);
 	case Gen::ShapeType::circle:

src/chart/rendering/markers/abstractmarker.h

@@ -35,6 +35,7 @@ class AbstractMarker
 	Geom::Point center;
 	Geom::Rect dataRect;
 	double radius{};
+	Events::Targets::Marker::DataPosition dataPosition;
 
 	[[nodiscard]] Geom::Rect getBoundary() const;
 	[[nodiscard]] Geom::Line getLine() const;

src/chart/rendering/markers/circlemarker.cpp

@@ -38,6 +38,11 @@ CircleMarker::CircleMarker(const Gen::Marker &marker,
 	dataRect.pos = pos;
 	dataRect.size = Geom::Size();
 	radius = fabs(coordSys.verConvert(r));
+
+	dataPosition = {
+	    this->getLabelPos(Styles::MarkerLabel::Position::top,
+	            coordSys)
+	        .end};
 }
 
 }

src/chart/rendering/markers/connectingmarker.cpp

@@ -158,6 +158,11 @@ ConnectingMarker::ConnectingMarker(const DrawingContext &ctx,
 
 	dataRect.pos = isLine ? points[2] : points[1];
 	dataRect.size = Geom::Size{points[2] - dataRect.pos};
+
+	dataPosition = {
+	    this->getLabelPos(Styles::MarkerLabel::Position::top,
+	            ctx.coordSys)
+	        .end};
 }
 
 const Gen::Marker *ConnectingMarker::getPrev(

src/chart/rendering/markers/rectanglemarker.cpp

@@ -16,6 +16,7 @@ namespace Vizzu::Draw
 {
 
 RectangleMarker::RectangleMarker(const Gen::Marker &marker,
+    const CoordinateSystem &coordSys,
     const Gen::Options &options,
     const Styles::Chart &style) :
     SingleDrawMarker(marker, options, Gen::ShapeType::rectangle)
@@ -83,6 +84,11 @@ RectangleMarker::RectangleMarker(const Gen::Marker &marker,
 	dataRect.pos = points[0];
 	dataRect.size = Geom::Size{points[2] - points[0]};
 	radius = 0;
+
+	dataPosition = {
+	    this->getLabelPos(Styles::MarkerLabel::Position::top,
+	            coordSys)
+	        .end};
 }
 
 }

src/chart/rendering/markers/rectanglemarker.h

@@ -10,6 +10,7 @@ class RectangleMarker : public SingleDrawMarker
 {
 public:
 	RectangleMarker(const Gen::Marker &marker,
+	    const CoordinateSystem &coordSys,
 	    const Gen::Options &options,
 	    const Styles::Chart &style);
 };