tdf#90749 chart: add leader lines to custom data label positions

also export them as CustomXML extension for MSO interoperability.

Note: pie chart is not yet supported.

See commit 4223ff2be69f03e571464b0b09ad0d278918631b
( tdf#48436 Chart: add CustomLabelPosition UNO API property)

Change-Id: Ia8142408414d4ad8f689d789386db50038ed13f6
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/88531
Tested-by: László Németh <nemeth@numbertext.org>
Reviewed-by: László Németh <nemeth@numbertext.org>

3 files changed, 49 insertions, 1 deletions

diff --git a/chart2/qa/extras/chart2export.cxx b/chart2/qa/extras/chart2export.cxx
index b9d5873052ba..88c7d154d170 100644
--- a/chart2/qa/extras/chart2export.cxx
+++ b/chart2/qa/extras/chart2export.cxx
@@ -136,6 +136,7 @@ public:
     void testCustomDataLabel();
     void testCustomPositionofDataLabel();
     void testCustomDataLabelMultipleSeries();
+    void testLeaderLines();
     void testNumberFormatExportPPTX();
     void testLabelSeparatorExportDOCX();
     void testChartTitlePropertiesColorFillPPTX();
@@ -254,6 +255,7 @@ public:
     CPPUNIT_TEST(testCustomDataLabel);
     CPPUNIT_TEST(testCustomPositionofDataLabel);
     CPPUNIT_TEST(testCustomDataLabelMultipleSeries);
+    CPPUNIT_TEST(testLeaderLines);
     CPPUNIT_TEST(testNumberFormatExportPPTX);
     CPPUNIT_TEST(testLabelSeparatorExportDOCX);
     CPPUNIT_TEST(testChartTitlePropertiesColorFillPPTX);
@@ -349,7 +351,8 @@ void Chart2ExportTest::registerNamespaces(xmlXPathContextPtr& pXmlXPathCtx)
         { "office", "urn:oasis:names:tc:opendocument:xmlns:office:1.0" },
         { "table", "urn:oasis:names:tc:opendocument:xmlns:table:1.0" },
         { "text", "urn:oasis:names:tc:opendocument:xmlns:text:1.0" },
-        { "xlink", "http://www.w3c.org/1999/xlink" }
+        { "xlink", "http://www.w3c.org/1999/xlink" },
+        { "c15", "http://schemas.microsoft.com/office/drawing/2012/chart" }
     };
     for(size_t i = 0; i < SAL_N_ELEMENTS(aNamespaces); ++i)
     {
@@ -2246,6 +2249,15 @@ void Chart2ExportTest::testCustomDataLabelMultipleSeries()
 
 }
 
+void Chart2ExportTest::testLeaderLines()
+{
+    load("/chart2/qa/extras/data/xlsx/", "testTdf90749.xlsx");
+    xmlDocPtr pXmlDoc = parseExport("xl/charts/chart", "Calc Office Open XML");
+    CPPUNIT_ASSERT(pXmlDoc);
+    assertXPath(pXmlDoc, "/c:chartSpace/c:chart/c:plotArea/c:lineChart/c:ser[1]/c:dLbls/c:extLst/c:ext/c15:showLeaderLines", "val", "1");
+    assertXPath(pXmlDoc, "/c:chartSpace/c:chart/c:plotArea/c:lineChart/c:ser[2]/c:dLbls/c:extLst/c:ext/c15:showLeaderLines", "val", "1");
+}
+
 void Chart2ExportTest::testNumberFormatExportPPTX()
 {
     load("/chart2/qa/extras/data/pptx/", "tdf115859.pptx");
diff --git a/chart2/qa/extras/data/xlsx/testTdf90749.xlsx b/chart2/qa/extras/data/xlsx/testTdf90749.xlsx
new file mode 100644
index 000000000000..ca3bc806c03c
--- /dev/null
+++ b/chart2/qa/extras/data/xlsx/testTdf90749.xlsx
diff --git a/chart2/source/view/charttypes/VSeriesPlotter.cxx b/chart2/source/view/charttypes/VSeriesPlotter.cxx
index b6382943b418..2c46743696f6 100644
--- a/chart2/source/view/charttypes/VSeriesPlotter.cxx
+++ b/chart2/source/view/charttypes/VSeriesPlotter.cxx
@@ -19,6 +19,7 @@
 
 #include <memory>
 #include <VSeriesPlotter.hxx>
+#include <BaseGFXHelper.hxx>
 #include <VLineProperties.hxx>
 #include <ShapeFactory.hxx>
 
@@ -86,6 +87,7 @@
 namespace chart {
 
 using namespace ::com::sun::star;
+using namespace ::com::sun::star::chart;
 using namespace ::com::sun::star::chart2;
 using ::com::sun::star::uno::Reference;
 using ::com::sun::star::uno::Sequence;
@@ -721,7 +723,41 @@ uno::Reference< drawing::XShape > VSeriesPlotter::createDataLabel( const uno::Re
         {
             awt::Point aRelPos = rDataSeries.getLabelPosition(aTextShapePos, nPointIndex);
             if( aRelPos.X != -1 )
+            {
                 xTextShape->setPosition(aRelPos);
+                if( !m_xChartTypeModel->getChartType().equalsIgnoreAsciiCase(CHART2_SERVICE_NAME_CHARTTYPE_PIE) )
+                {
+                    sal_Int32 nX1 = rScreenPosition2D.X;
+                    sal_Int32 nY1 = rScreenPosition2D.Y;
+                    sal_Int32 nX2 = nX1;
+                    sal_Int32 nY2 = nY1;
+                    ::basegfx::B2IRectangle aRect(BaseGFXHelper::makeRectangle(aRelPos, xTextShape->getSize()));
+                    if (nX1 < aRelPos.X)
+                        nX2 = aRelPos.X;
+                    else if (nX1 > aRect.getMaxX())
+                        nX2 = aRect.getMaxX();
+
+                    if (nY1 < aRect.getMinY())
+                        nY2 = aRect.getMinY();
+                    else if (nY1 > aRect.getMaxY())
+                        nY2 = aRect.getMaxY();
+
+                    //when the line is very short compared to the page size don't create one
+                    ::basegfx::B2DVector aLength(nX1 - nX2, nY1 - nY2);
+                    double fPageDiagonaleLength = sqrt(double(m_aPageReferenceSize.Width)*double(m_aPageReferenceSize.Width) + double(m_aPageReferenceSize.Height)*double(m_aPageReferenceSize.Height));
+                    if ((aLength.getLength() / fPageDiagonaleLength) >= 0.01)
+                    {
+                        drawing::PointSequenceSequence aPoints(1);
+                        aPoints[0].realloc(2);
+                        aPoints[0][0].X = nX1;
+                        aPoints[0][0].Y = nY1;
+                        aPoints[0][1].X = nX2;
+                        aPoints[0][1].Y = nY2;
+
+                        m_pShapeFactory->createLine2D(xTarget, aPoints, new VLineProperties);
+                    }
+                }
+            }
         }
 
         // in case legend symbol has to be displayed, text shape position is