New Feature: Rotation by Selecting North

freehandrastergeoreferencer.py

@@ -29,6 +29,7 @@
     MoveRasterMapTool,
     RotateRasterMapTool,
     ScaleRasterMapTool,
+    SelectNorthMapTool,
 )
 from .freehandrastergeoreferencerdialog import FreehandRasterGeoreferencerDialog
 
@@ -78,6 +79,15 @@ def initGui(self):
         self.actionRotateRaster.triggered.connect(self.rotateRaster)
         self.actionRotateRaster.setCheckable(True)
 
+        self.actionSelectNorth = QAction(
+            QIcon(":/plugins/freehandrastergeoreferencer/iconSelectNorth.png"),
+            "Select North",
+            self.iface.mainWindow())
+        self.actionSelectNorth.setObjectName(
+            "FreehandRasterGeoreferencingLayerPlugin_SelectNorth")
+        self.actionSelectNorth.triggered.connect(self.selectNorth)
+        self.actionSelectNorth.setCheckable(True)
+
         self.actionScaleRaster = QAction(
             QIcon(":/plugins/freehandrastergeoreferencer/iconScale.png"),
             "Scale raster",
@@ -170,6 +180,7 @@ def initGui(self):
         self.toolbar.addAction(self.actionAddLayer)
         self.toolbar.addAction(self.actionMoveRaster)
         self.toolbar.addAction(self.actionRotateRaster)
+        self.toolbar.addAction(self.actionSelectNorth)
         self.toolbar.addWidget(self.spinBoxRotate)
         self.toolbar.addAction(self.actionScaleRaster)
         self.toolbar.addAction(self.actionAdjustRaster)
@@ -190,6 +201,8 @@ def initGui(self):
         self.moveTool.setAction(self.actionMoveRaster)
         self.rotateTool = RotateRasterMapTool(self.iface)
         self.rotateTool.setAction(self.actionRotateRaster)
+        self.selectNorthTool = SelectNorthMapTool(self.iface)
+        self.selectNorthTool.setAction(self.actionSelectNorth)
         self.scaleTool = ScaleRasterMapTool(self.iface)
         self.scaleTool.setAction(self.actionScaleRaster)
         self.adjustTool = AdjustRasterMapTool(self.iface)
@@ -236,6 +249,7 @@ def checkCurrentLayerIsPluginLayer(self):
         ):
             self.actionMoveRaster.setEnabled(True)
             self.actionRotateRaster.setEnabled(True)
+            self.actionSelectNorth.setEnabled(True)
             self.actionScaleRaster.setEnabled(True)
             self.actionAdjustRaster.setEnabled(True)
             self.actionGeoref2PRaster.setEnabled(True)
@@ -261,6 +275,7 @@ def checkCurrentLayerIsPluginLayer(self):
         else:
             self.actionMoveRaster.setEnabled(False)
             self.actionRotateRaster.setEnabled(False)
+            self.actionSelectNorth.setEnabled(False)
             self.actionScaleRaster.setEnabled(False)
             self.actionAdjustRaster.setEnabled(False)
             self.actionGeoref2PRaster.setEnabled(False)
@@ -339,6 +354,9 @@ def moveRaster(self):
     def rotateRaster(self):
         self._toggleTool(self.rotateTool)
 
+    def selectNorth(self):
+        self._toggleTool(self.selectNorthTool)
+
     def scaleRaster(self):
         self._toggleTool(self.scaleTool)
 

freehandrastergeoreferencer_maptools.py

@@ -815,3 +815,90 @@ def _addDisplacementToPoint(self, rubberBand, point, doUpdate):
         x = point.x() + self.endPoint.x() - self.startPoint.x()
         y = point.y() + self.endPoint.y() - self.startPoint.y()
         self.rubberBandExtent.addPoint(QgsPointXY(x, y), doUpdate)
+
+class SelectNorthMapTool(QgsMapToolEmitPoint):
+    def __init__(self, iface):
+        self.iface = iface
+        self.canvas = iface.mapCanvas()
+        QgsMapToolEmitPoint.__init__(self, self.canvas)
+
+        self.rasterShadow = RasterShadowMapCanvasItem(self.canvas)
+
+        self.firstPoint = None
+        self.secondPoint = None
+
+        # Marker for the starting point
+        self.rubberBandOriginPoint = QgsRubberBand(self.canvas, QgsWkbTypes.PointGeometry)
+        self.rubberBandOriginPoint.setColor(Qt.red)
+        self.rubberBandOriginPoint.setIcon(QgsRubberBand.ICON_X)
+        self.rubberBandOriginPoint.setIconSize(7)
+        self.rubberBandOriginPoint.setWidth(2)
+
+        # Line for the North Line
+        self.rubberBandLine = QgsRubberBand(self.canvas, QgsWkbTypes.LineGeometry)
+        self.rubberBandLine.setColor(Qt.red)
+        self.rubberBandLine.setWidth(1)
+
+        self.isLayerVisible = True
+
+        self.reset()
+
+    def setLayer(self, layer):
+        self.layer = layer
+
+    def reset(self):
+        self.secondPoint = self.firstPoint = None
+        self.isEmittingPoint = False
+        self.rubberBandOriginPoint.reset(QgsWkbTypes.PointGeometry)
+        self.rubberBandLine.reset(QgsWkbTypes.LineGeometry)
+        self.layer = None
+
+    def deactivate(self):
+        QgsMapToolEmitPoint.deactivate(self)
+        self.reset()
+
+    def canvasPressEvent(self, e):
+        self.firstPoint = self.toMapCoordinates(e.pos())
+        self.isEmittingPoint = True
+
+        # Set the starting point marker to the first position and show
+        self.rubberBandOriginPoint.reset(QgsWkbTypes.PointGeometry)
+        self.rubberBandOriginPoint.addPoint(self.firstPoint, True)
+        self.rubberBandOriginPoint.show()
+
+        self.layer.history.append(
+        {
+            "action": "rotation",
+            "rotation": self.layer.rotation,
+            "center": self.layer.center,
+        })
+
+    def canvasReleaseEvent(self, e):
+        self.isEmittingPoint = False
+        self.secondPoint = self.toMapCoordinates(e.pos())
+
+        azimuth = -self.firstPoint.azimuth(self.secondPoint)
+        self.layer.setRotation(azimuth + self.layer.rotation)
+
+        self.layer.repaint()
+
+        self.layer.commitTransformParameters()
+
+        self.rubberBandLine.reset(QgsWkbTypes.LineGeometry)
+        self.rubberBandOriginPoint.reset(QgsWkbTypes.PointGeometry)
+        self.rasterShadow.reset()
+
+        self.firstPoint = self.secondPoint = None
+
+    def canvasMoveEvent(self, e):
+        if not self.isEmittingPoint:
+            return
+
+        self.secondPoint = self.toMapCoordinates(e.pos())
+        self.showDisplacement(self.firstPoint, self.secondPoint)
+
+    def showDisplacement(self, startPoint, endPoint):
+        self.rubberBandLine.reset(QgsWkbTypes.LineGeometry)
+        self.rubberBandLine.addPoint(startPoint, False)
+        self.rubberBandLine.addPoint(endPoint, True)  # true to update canvas
+        self.rubberBandLine.show()

gen_icons.bat

@@ -8,5 +8,5 @@ convert -size 24x24 xc:purple -gravity Center \( -density 288 -size 96x96 xc:non
 convert -size 24x24 xc:yellow -gravity Center \( -density 288 -size 96x96 xc:none -fill 'green' -font "Consolas"  -pointsize 14  -annotate 0 'SC' -resize 25% -fuzz 10% -trim \) -composite +repage iconScale.png
 convert -size 24x24 xc:white -gravity Center \( -density 288 -size 96x96 xc:none -fill 'black' -font "Consolas"  -pointsize 14  -annotate 0 'T-' -resize 25% -fuzz 10% -trim \) -composite +repage iconTransparencyDecrease.png
 convert -size 24x24 xc:black -gravity Center \( -density 288 -size 96x96 xc:none -fill 'white' -font "Consolas"  -pointsize 14  -annotate 0 'T+' -resize 25% -fuzz 10% -trim \) -composite +repage iconTransparencyIncrease.png
-
+convert -size 24x24 xc:orange -gravity Center \( -density 288 -size 96x96 xc:none -fill 'purple' -font "Consolas"  -pointsize 14  -annotate 0 'N' -resize 25% -fuzz 10% -trim \) -composite +repage iconSelectNorth.png
 

resources.qrc

@@ -4,6 +4,7 @@
         <file>iconAdd.png</file>
         <file>iconMove.png</file>
         <file>iconRotate.png</file>
+        <file>iconSelectNorth.png</file>
         <file>iconScale.png</file>
         <file>iconAdjust.png</file>
         <file>icon2Points.png</file>