Combo Overlay with masking

This page describes a use case for implementing a combo overlay.

Use Case Description

How can I 'mask' (filter out) all values of a rainfall overlay that is not of the highest range? In this case we use the default highest range of 50 cm or more.

For this we need to add a rainfall overlay and a formula we can use to mask the values that are too low.

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  Rainfall overlay

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  Combo Overlay with masking

Formula

We want to only show the highest rainfall values, so we want to use all values that are greater then 49 cm (0,049m), and only of the last toimeframe (25 in this case). This gives us the following formula

MUL(GTE(A25, 0.049), A25)

Where A25 is the last time frame of the rainfall overlay.

How to

How to add a Combo Overlay with features:

1. Give each building or area you want to include a specific attribute (ex: 'FOO', 'BAR', 'BOO',...)
2. Create three Average Overlays, set the cell averaging distance to the desired range
3. Add a Combo Overlay and select the Average overlays in each slot (A,B and C)
4. Enter the formula in the Formula field
5. Select 'Update Now' in case auto-update was disabled

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  Select Distance Sight Overlay

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  Select Legend tab

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  Select "Has Custom Legend"

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  Add new entry

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  Edit the name, value and color of the entry