I need help making an expression for labelling points, such that the label is placed in one of the 8 quadrants (above point excluded), based on the azimuth field of the point.
For example, if the azimuth is from 338-23 degrees, place in quadrant 1, if the azimuth is from 24-69 degrees, place in quadrant 2, and so on.
You can databind the label Placement Quadrant with this expression structure:
CASE
WHEN azimuth < 23 OR azimuth > 338 THEN
1
WHEN azimuth > 24 AND azimuth < 69 THEN
2
ELSE
3
END
You may also need an expression calculating a more appropriate offset depending on the azimuth.
Update:
The offset can databind to an expression like this:
CASE
WHEN azimuth < 23 OR azimuth > 338 THEN
'0,-1'
WHEN azimuth > 24 AND azimuth < 69 THEN
'1,0'
ELSE
'-1,0'
END
Negative x-values moves label west. Negative y-values moves label north. So '0,-1' means an x,y offset in 0 for x and 1 up north. Pick the unit used as map units, if you not using lat-long coordinates.
For quadrant:
CASE
WHEN "Strike" > 325 OR "Strike" <= 25 THEN 5
WHEN "Strike" > 25 AND "Strike" <= 70 THEN 8
WHEN "Strike" > 70 AND "Strike" <= 115 THEN 7
WHEN "Strike" > 115 AND "Strike" <= 160 THEN 6
WHEN "Strike" > 160 AND "Strike" <= 205 THEN 3
WHEN "Strike" > 205 AND "Strike" <= 250 THEN 0
WHEN "Strike" > 250 AND "Strike" <= 295 THEN 1
WHEN "Strike" > 295 AND "Strike" <= 325 THEN 2
END
For offset:
CASE
WHEN "Strike" >= 0 AND "Strike" <=20 THEN '3,0'
WHEN "Strike" > 20 AND "Strike" <=45 THEN '2,-1'
WHEN "Strike" > 45 AND "Strike" <= 90 THEN '0,1'
WHEN "Strike" > 90 AND "Strike" <= 135 THEN '-1,1'
WHEN "Strike" > 135 AND "Strike" <= 180 THEN '-1.5,0'
WHEN "Strike" > 180 AND "Strike" <= 225 THEN '-1.5,-0.5'
WHEN "Strike" > 225 AND "Strike" <= 270 THEN '0,-1'
WHEN "Strike" > 270 AND "Strike" <= 315 THEN '0,-1'
WHEN "Strike" > 315 AND "Strike" <= 359 THEN '3,-0.5'
END
