DeviceSourceManager KeyUp/KeyDown Event

Questions
1

Quick question, does the DeviceSourceManager have a keyup/keydown event listener or would I need to implement my own solution using addeventlistener? Or, has anyone come up with a solution for keyup/keydown events?

Also I’m surprised no one has asked this.

2

Hi, and welcome to the forum!

The DSM can provide you with the native keyboard event, if you don’t want to poll on each frame:

dsm.onDeviceConnectedObservable.add((device) => {
  if(device.deviceType === BABYLON.DeviceType.Keyboard) {
    dsm.getDeviceSource(BABYLON.DeviceType.Keyboard).onInputChangedObservable.add((event) => {
        console.log(event);
    })
  }
})

If you want to poll and check, you will need to know the keyCode (arrow up is 38, for example) and then poll on each frame:

if (dsm.getDeviceSource(BABYLON.DeviceType.Keyboard)) {
   if (dsm.getDeviceSource(BABYLON.DeviceType.Keyboard).getInput(38) === 1) {
     // up is pressed
   }
}

I am sure @PolygonalSun can help with further questions about the DSM :slight_smile:

1 Like
3

Appreciate your reply thank you. The first one works the way I was expecting. I can bind some bool to the current and previous state or something to create a keyup event listener.

Just to point out that you could have used the device object passed into the onDeviceConnectedObservable.add() listener.

dsm.onDeviceConnectedObservable.add((device) => {
  if(device.deviceType === BABYLON.DeviceType.Keyboard) {
    device.onInputChangedObservable.add((event) => {
        console.log(event);
    })
  }
})

And my preliminary code for a keyup event is

let keyup = false

deviceSourceManager.onDeviceConnectedObservable.add((device) => {
  if (device.deviceType === Devices.DeviceType.Keyboard) {
    device.onInputChangedObservable.add((event) => {
      console.log(event)
      console.log('KeyStart: ', keyup)
      if (event.currentState == 0) {
        keyup = true
        console.log('KeyUP: ', keyup)
      } else {
        keyup = false
        console.log('Keydown: ', keyup)
      }
      console.log('KeyEnd: ', keyup)
    })
  }
})

That boolean isn’t necessary, and actually behaves in an odd way lol but it was a good test to see that keyup/down is accurately being tracked. The if statement works perfectly though. Might use a switch or something to call behaviors from somewhere else but this is exactly what I was looking for.

I appreciate your response and your code.

Thanks again.

Edit: Oh just in case someone sees this is confused by why I’m using something called Devices to call the deviceType. I import individual features so this is the import line.

import * as Devices from '@babylonjs/core/DeviceInput'

Thats where I’m getting access to them. Hope that helps a bit more.

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