LiDAR data can be used to measure building heights (see this page on how to get everything you need!).

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To measure a height using this set up:

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Find and open the relevant file from the "LiDAR 2 / Blocks" folder. The file you've opened consists arrays of many points, coloured by layer:

Purple in this case represents the ground surface, and Yellow represents the roof surfaces. It's best to hide all other layers for now. (By clicking the lightbulb symbol beside the layer in the layer manager panel).

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Type the "Line" command or click to "Draw a Single Line" (Under the Polyline button in the Standard toolset). Options for drawing a line will now appear in the command line area. Click "Vertical" to constrain your line to the Z axis.

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With the new line selected, and the Object Properties panel displayed, click the "Details..." button, which should be at the bottom of the panel. This brings up a new window and is the easiest way to check the length of the line.