The Get node for the float value of Custom Axis Mappings only returns 0.0 when called from Blueprints other than the Controller. Input from the player does not affect the value.
Note: this works as expected when used in the Controller, but Get Controller > Get CustomAxisMapping always returns 0.0 regardless of player input. The InputAxis Event, however, works as expected in all BPs.
1. Launch: UE4Editor.exe
2. Create a new empty project
3. Create a new Axis Mapping
4. Assign the Left key to the new mapping with a scale of 1.0
5. Create a new Character Blueprint
6. Get Player Controller (Player Index 0)
7. Get the custom Axis Mapping from the Controller
8. Print this float value on Event Tick
9. Create a new Game Mode
10. Make the new Character Blueprint the default
12. Press the Left key
The custom axis mapping's value remains at 0.0 when the Left key is pressed.
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