Solve the problem of QGIS coordinate system matching and conversion
Problem scenario 1: When the layer is displayed, the engineering coordinate system is inconsistent with the coordinate system corresponding to the coordinates below.
As shown in the figure above, the engineering coordinate system in the lower right corner is a UTM projected coordinate system, but the coordinates at the bottom are still longitude and latitude (corresponding to the 84 geographical coordinate system).
solution:
Right-click the layer and set the layer coordinate system CRS to the coordinate system corresponding to the coordinate display (that is, the coordinate system of the layer itself). As shown in the figure below, set the layer CRS to the 84 geographic coordinate system and the problem is solved.
Problem scenario 2: There is still no way to select metric units when generating grids or buffers, as shown in the figure below.
solution:
1. Change the engineering coordinate system to the projected coordinate system.
2. Check whether the problem in Scenario 1 exists. If it exists, you need to change the CRS displayed on the layer to the layer file coordinate system, as shown in the figure below.
3. If the layer file is in a geographical coordinate system, it needs to be reprojected to a projected coordinate system; if the layer file is in projected coordinates, it does not matter.
After completing the above 3 points, the problem will be solved.
Problem scenario 3: The coordinates of elements crawled on Baidu and Amap do not match the open street map
The coordinates on Baidu Maps and Amap are encrypted and require the GeoHey coordinate conversion plug-in. Open QGIS directly, search for and install it in the plug-in library (plug-in-manage and install plug-ins-not installed-search for GeoHey).
For a more specific explanation, please refer to: Conversion between Baidu, Amap and WGS84 coordinate systems in QGIS! worth collecting