Differences

This shows you the differences between two versions of the page.

--- kb:rotation [2013/05/12 17:51] – external edit 127.0.0.1
+++ kb:rotation [2016/09/25 21:07] – enviadmin
@@ Line 6: / Line 6: @@
 For example if a street canyon is analysed that has a different orientation, it is not clever to turn the buildings lining the street into "steps".
-As the correct interpretation of the sign of rotation is sometimes a bit tricky, have a look at the following sketch:
+As the correct interpretation of the sign of rotation is sometimes a bit tricky, depending on which perspective you take,have a look at the following sketch:
 {{ ::remarks_for_rotation.jpg?nolink |}}
-The model area (white square) in this example is rotated 25° clockwise above the original map (grey square). The direction is always related to the model area, not to the map. \\
+In the drawing above on the left, no model rotation is applied. The rectangular model domain is orientated like the map with the left and right sides aligned to the North-South direction.
-So if you want to fit the map to your model area, you have to turn it exactly in the counter-direction ! Also, if you draw a north-arrow in your model area, a clockwise rotation will cause an anti-clockwise turn of the north arrow! \\
-Confusing, I know...
+Now, lets consider that we want to rotate the model area (white square) by 25° clockwise to getter a better fit to the area we are interested in.
+So we rotate the area (white square) by 25° out of the original North-South direction of the map (gray square). That is easy, but look what it makes to the North-Arrow when we edit our new model area (which will be of course edited in the perspective of the area, not of the map): The North-Arrow still must point into the original align of the map. so actually, the North-Arrow in your model will be rotated anti-clockwise if you have a clockwise rotated model domain!
 To change the model orientation, use the ENVI-met SPACES.