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@ThomasG77
Last active September 12, 2022 04:33
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Add this script in startup.py to now see zoom for EPSG 3857 when the canevas is using it
from math import cos, log, pi
from qgis.utils import iface
from qgis.PyQt.QtWidgets import QLabel
# Not needed here but could be useful later
# def getScale(zoom_level, screen_dpi=96, latitude=0):
# resolution = (6378137.0 * 2 * pi / 256) * cos(latitude) / (2**zoom_level)
# return (screen_dpi * 1/0.0254 * resolution)
def getZoomLevel(scale, screen_dpi=96, latitude=0):
resolution = scale / (screen_dpi * 1/0.0254)
zoom_level = ((6378137.0 * 2 * pi / 256) * cos(latitude)) / resolution
return log(zoom_level)/log(2)
canvas = iface.mapCanvas()
labelZoomNumberEpsg3857 = QLabel()
iface.mainWindow().statusBar().addPermanentWidget(labelZoomNumberEpsg3857)
def changeZoomNumberOsm(scale):
rounded_zoom_level = round(getZoomLevel(scale), 2)
labelZoomNumberEpsg3857.setText("Zoom level : {}".format(str(rounded_zoom_level)))
canvas.scaleChanged.connect(changeZoomNumberOsm)
def showHideZoomLevel():
if canvas.mapSettings().destinationCrs().authid() == "EPSG:3857":
labelZoomNumberEpsg3857.show()
else:
labelZoomNumberEpsg3857.hide()
canvas.destinationCrsChanged.connect(showHideZoomLevel)
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