Fix offset background when drawing rotated text using QgsTextRenderer

qgis · Oct 6, 2021 · de20bca · de20bca
1 parent 8e52596
commit de20bca
Show file tree

Hide file tree

Showing 4 changed files with 32 additions and 0 deletions.
diff --git a/src/core/textrenderer/qgstextrenderer.cpp b/src/core/textrenderer/qgstextrenderer.cpp
@@ -768,6 +768,7 @@ void QgsTextRenderer::drawBackground( QgsRenderContext &context, QgsTextRenderer
   // shared calculations between shapes and SVG
 
   // configure angles, set component rotation and rotationOffset
+  const double originAdjustRotationRadians = -component.rotation;
   if ( background.rotationType() != QgsTextBackgroundSettings::RotationFixed )
   {
     component.rotation = -( component.rotation * 180 / M_PI ); // RotationSync
@@ -834,6 +835,15 @@ void QgsTextRenderer::drawBackground( QgsRenderContext &context, QgsTextRenderer
                                         component.origin.y() - height / 2.0 + originAdjust );
             break;
         }
+
+        // apply rotation to center point
+        if ( !qgsDoubleNear( originAdjustRotationRadians, 0 ) )
+        {
+          const double dx = component.center.x() - component.origin.x();
+          const double dy = component.center.y() - component.origin.y();
+          component.center.setX( component.origin.x() + ( std::cos( originAdjustRotationRadians ) * dx - std::sin( originAdjustRotationRadians ) * dy ) );
+          component.center.setY( component.origin.y() + ( std::sin( originAdjustRotationRadians ) * dx + std::cos( originAdjustRotationRadians ) * dy ) );
+        }
         break;
       }
 

diff --git a/tests/src/python/test_qgstextrenderer.py b/tests/src/python/test_qgstextrenderer.py
@@ -1522,6 +1522,28 @@ def testDrawBackgroundRectangleFixedSizeMapUnits(self):
         format.background().setSizeUnit(QgsUnitTypes.RenderMapUnits)
         assert self.checkRender(format, 'background_rect_mapunits', QgsTextRenderer.Background)
 
+    def testDrawBackgroundRectangleFixedSizeWithRotatedText(self):
+        format = QgsTextFormat()
+        format.setFont(getTestFont('bold'))
+        format.setSize(40)
+        format.background().setEnabled(True)
+        format.background().setType(QgsTextBackgroundSettings.ShapeRectangle)
+        format.background().setSize(QSizeF(20, 20))
+        format.background().setSizeType(QgsTextBackgroundSettings.SizeFixed)
+        format.background().setSizeUnit(QgsUnitTypes.RenderMillimeters)
+        assert self.checkRenderPoint(format, 'background_rect_fixed_rotated_text', angle=3.141 / 4)
+
+    def testDrawBackgroundRectangleBufferSizeWithRotatedText(self):
+        format = QgsTextFormat()
+        format.setFont(getTestFont('bold'))
+        format.setSize(40)
+        format.background().setEnabled(True)
+        format.background().setType(QgsTextBackgroundSettings.ShapeRectangle)
+        format.background().setSize(QSizeF(2, 3))
+        format.background().setSizeType(QgsTextBackgroundSettings.SizeBuffer)
+        format.background().setSizeUnit(QgsUnitTypes.RenderMillimeters)
+        assert self.checkRenderPoint(format, 'background_rect_buffer_rotated_text', angle=3.141 / 4)
+
     def testDrawBackgroundRectangleMultilineFixedSizeMapUnits(self):
         format = QgsTextFormat()
         format.setFont(getTestFont('bold'))

diff --git a/...rer/background_rect_buffer_rotated_text/background_rect_buffer_rotated_text.png b/...rer/background_rect_buffer_rotated_text/background_rect_buffer_rotated_text.png
diff --git a/...derer/background_rect_fixed_rotated_text/background_rect_fixed_rotated_text.png b/...derer/background_rect_fixed_rotated_text/background_rect_fixed_rotated_text.png