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Using Model Rotation
It can be handy to use a different model orientation than the default one (Y-axis pointing to North).
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, depending on which perspective you take,have a look at the following sketch:
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.
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.
All input and output values are referring to the normal co-ordinate system.
A wind direction of 90 degrees for example means that the wind comes from the east. If the model is rotated, this does not automatically mean that it comes from the right model side!
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