class ShapeTool(QgsMapTool):
#signal emitted when the mouse is clicked. This indicates that the tool finished its job
toolFinished = pyqtSignal()
def __init__(self, canvas, geometryType, param, type, color = QColor( 254, 178, 76, 63 )):
"""
Constructor
"""
QgsMapTool.__init__(self, canvas)
self.canvas = canvas
self.active = False
self.geometryType = self.tr(geometryType)
self.param=param
self.type=type
self.cursor=None
self.rubberBand = QgsRubberBand(self.canvas, QgsWkbTypes.PolygonGeometry)
self.setColor(color)
self.reset()
self.rotAngle = 0
self.currentCentroid = None
self.rotate = False
def setColor(self, mFillColor):
"""
Adjusting the color to create the rubber band
"""
self.rubberBand.setColor(mFillColor)
self.rubberBand.setWidth(1)
def reset(self):
"""
Resetting the rubber band
"""
self.startPoint = self.endPoint = None
self.isEmittingPoint = False
try:
self.rubberBand.reset(QgsWkbTypes.PolygonGeometry)
except:
pass
def rotateRect(self, centroid, e):
"""
Calculates the angle for the rotation.
"""
item_position = self.canvas.mapToGlobal(e.pos())
c = self.toCanvasCoordinates(centroid)
c = self.canvas.mapToGlobal(c)
rotAngle = pi - atan2(
item_position.y() - c.y(), item_position.x() - c.x())
return rotAngle
def canvasPressEvent(self, e):
"""
When the canvas is pressed the tool finishes its job
"""
# enforce mouse restoring if clicked right after rotation
QApplication.restoreOverrideCursor()
self.canvas.unsetMapTool(self)
self.toolFinished.emit()
def _baseDistanceInMeters(self):
"""
Calculates the distance in meters of 2 points 1 unit map away on
current canvas CRS.
:return: (float) distance in meters between two points 1 map unit apart
from each other.
"""
source_crs = self.canvas.mapSettings().destinationCrs()
dest_crs = QgsCoordinateReferenceSystem(3857)
tr = QgsCoordinateTransform(
source_crs, dest_crs, QgsCoordinateTransformContext())
p1t = QgsGeometry().fromPointXY(QgsPointXY(1, 0))
p1t.transform(tr)
p2t = QgsGeometry().fromPointXY(QgsPointXY(0, 0))
p2t.transform(tr)
return QgsDistanceArea().measureLine(p1t.asPoint(), p2t.asPoint())
def getAdjustedSize(self, size):
"""
If map unit is not metric, the figure to be drawn needs to have its
size adjusted. This is necessary because input parameters are designed
to be meters on tool's GUI.
:param size: (float) tool's radius/length reference size in meters.
:return: (float)
"""
source_crs = self.canvas.mapSettings().destinationCrs()
if source_crs.mapUnits() != QgsUnitTypes.DistanceMeters:
return size / self._baseDistanceInMeters()
return size
def canvasMoveEvent(self, e):
"""
Deals with mouse move event to update the rubber band position in the canvas
"""
ctrlIsHeld = QApplication.keyboardModifiers() == Qt2.ControlModifier
if e.button() != None and not ctrlIsHeld:
if self.rotate:
# change rotate status
self.rotate = False
QApplication.restoreOverrideCursor()
self.endPoint = self.toMapCoordinates( e.pos() )
elif e.button() != None and ctrlIsHeld \
and self.geometryType == self.tr(u"Square"):
# calculate angle between mouse and last rubberband centroid before holding control
self.rotAngle = self.rotateRect(self.currentCentroid, e)
if not self.rotate:
# only override mouse if it is not overriden already
QApplication.setOverrideCursor(QCursor(Qt2.BlankCursor))
self.rotate = True
if self.geometryType == self.tr(u"Circle"):
self.showCircle(self.endPoint)
elif self.geometryType == self.tr(u"Square"):
self.showRect(self.endPoint, sqrt(self.param)/2, self.rotAngle)
def showCircle(self, startPoint):
"""
Draws a circle in the canvas
"""
nPoints = 50
x = startPoint.x()
y = startPoint.y()
if self.type == self.tr('distance'):
r = self.getAdjustedSize(self.param)
self.rubberBand.reset(QgsWkbTypes.PolygonGeometry)
for itheta in range(nPoints+1):
theta = itheta*(2.0*pi/nPoints)
self.rubberBand.addPoint(QgsPointXY(x+r*cos(theta), y+r*sin(theta)))
self.rubberBand.show()
else:
r = self.getAdjustedSize(sqrt(self.param/pi))
self.rubberBand.reset(QgsWkbTypes.PolygonGeometry)
for itheta in range(nPoints+1):
theta = itheta*(2.0*pi/nPoints)
self.rubberBand.addPoint(QgsPointXY(x+r*cos(theta), y+r*sin(theta)))
self.rubberBand.show()
def showRect(self, startPoint, param, rotAngle=0):
"""
Draws a rectangle in the canvas
"""
self.rubberBand.reset(QgsWkbTypes.PolygonGeometry)
x = startPoint.x() # center point x
y = startPoint.y() # center point y
# rotation angle is always applied in reference to center point
# to avoid unnecessary calculations
c = cos(rotAngle)
s = sin(rotAngle)
# translating coordinate system to rubberband centroid
param = self.getAdjustedSize(param)
for posx, posy in ((-1, -1), (-1, 1), (1, 1), (1, -1)):
px = posx * param
py = posy * param
pnt = QgsPointXY(px * c - py * s + x, py * c + px * s + y)
self.rubberBand.addPoint(pnt, False)
self.rubberBand.setVisible(True)
self.rubberBand.updateRect()
self.rubberBand.update()
self.rubberBand.show()
self.currentCentroid = startPoint
def deactivate(self):
"""
Deactivates the tool and hides the rubber band
"""
self.rubberBand.hide()
QgsMapTool.deactivate(self)
# restore mouse in case tool is disabled right after rotation
QApplication.restoreOverrideCursor()
def activate(self):
"""
Activates the tool
"""
QgsMapTool.activate(self)
