How to Take Control of the Mouse in Lyra

Lyra uses CommonUI to manage the menu system and widgets in Lyra-based games. For a big picture overview of how it is all plugged together, see my Lyra Input Overview.

This YouTube Video Tutorial covers the material outlined in this dev log. Reading this log and watching the video together may help make the material more clear.

This tutorial will show you how to take full control over the mouse and input mode in your Lyra-based game.

This is useful if you want to:

• Allow the user to use the mouse while playing the game (e.g. not just for menu navigation)
• Change input modes during game play

Conceptual Overview

You must use CommonUI to change input modes. DO NOT use old UE4 methods, they do not work in Lyra.

1. Create your own “change input mode” method
   • Must call CommonUI’s Action Router SetActiveUIInputConfig method to commit the input mode change
   • Example: Xisted Set Input Mode
2. (optional) Override the base CommonUI Action Router
   • Completely override its ApplyUIInputConfig method
   • Example: Xisted UI Action Router

Example: Xisted Set Input Mode

File Type	URL
Header	XistedInputModeStatics.h
CPP	XistedInputModeStatics.cpp

This is an example of a Blueprint Function Library that provides a single static C++ method that can be used by either C++ or Blueprint code.

In this example, there are 3 possible switches:

• Set mouse visible? (bool)
• Ignore look input? (bool)
• Ignore move input? (bool)

You must pass in the Player Controller whose input mode you wish to change, and then based on the settings of these 3 switches, it will compute the appropriate CommonUI FUIInputConfig, set the mouse visibility and then call the CommonUI Action Router’s SetActiveUIInputConfig method.

C++ Usage Example

APlayerController* PC = /*YOU_MUST_SET_THIS*/;

bool bVisibleMouse = true;
bool bIgnoreLook = true;
bool bIgnoreMove = false;

UXistedInputModeStatics::XistedSetInputMode(PC, bVisibleMouse, bIgnoreLook, bIgnoreMove);

Blueprint Usage Example

In this example Gameplay Ability blueprint, we’re calling the static blueprint function library method XistedSetInputMode to change the input mode of the Player Controller that currently owns the ability.

Make it work like you want

You may want a different implementation. Great. Make it work the way you want. This code will get you started and you can customize as you like.

Things to Pay Attention To

In this example code, I have it set to use CapturePermanently_IncludingInitialMouseDown mouse capture mode whenever the mouse is invisible. This is the typical setting for an FPS game where the mouse is used for the look/aim and generally you don’t want it to be visible.

During the time when we DO want the mouse to be visible, I’m instead using CaptureDuringMouseDown which doesn’t capture the mouse UNLESS the mouse is down. This means that every single click (when the mouse is over the game viewport) will be sent to the Game and can be used in game.

If you instead use something like NoCapture, then the first click will be “lost” and only every other click will go to the game.

These settings, and more, are highly game specific, so play with them until you find the settings that are right for your game.

Example: Xisted UI Action Router

File Type	URL
Header	XistedUIActionRouter.h
CPP	XistedUIActionRouter.cpp

In this example override of UCommonUIActionRouterBase, I implement a complete override of the ApplyUIInputConfig method. See the comments in the header file for more details.

Note that you DO NOT need to keep the same implementation I am using here. You may want your game input modes to function differently. Modify the implementation as needed.

Also note that you may not actually need to change the default Common UI Action Router. To know whether you do, see the video tutorial section: “How to know if you must override Apply UI Input Config”