#Hololens – How to use clases TapToPlace and InitialScanManager

Hi !

Yesterday I wrote about a custom solution I made to have Tap to Place feature in an Hololens App. The main set of features was

• We can perform an initial scan of an environment, based on a time constraint. Also we can continue the scan process if we don’t find a minimum of number of planes for floor or wall
• We can associate one class to an hologram to have the Tap to Place feature
• This process also allow us to validate if we can place the hologram in a vertical (wall) or horizontal (floor) plane
• The validation process also have some visual features like change the color of a box collider from red to green depending if we can or can’t place an object and also cast a shadow with the final location of the hologram

The “InitialScanManager.cs” is the one I use to perform the initial environment scan. I usually add this class to an Empty Game Object. The main properties to use are this ones:

• Limit Scanning by Time and Scan Time, definen how the scan process will be performed. If we set a Scan Time value of N, and check the Limit Scan time, the app will scan the environment for N seconds and then will stop the scan process
• Minimum Floor and Minimum Wall defines the minimum amount of frames to be searched in the floor and the wall
• Player, this is optional for the main hologram. When the scan process start it will be hide and when the scan process ends the player will be show again
• DebugTextPlayer, optional, a TextMesh used for debug actions

The class “TapToPlacePlayer.cs” is the one we must associate to the element where we want this feature. The main properties are

• Placeable Bounds and Non Placeable Bounds Materials are materials used when we start the “place mode”. I create a collider with this materials and the class change the materials based on if we can place or not the hologram at the selected position
• Placeable Shadow and Non Placeable Shadow Materials are materials used to display the final position to be placed for the hologram
• Display Shadow defines if we want to show (or not) the final position of the hologram
• Placement Surface defines the positioning mode Horizontal or Vertical. I mean Floor or Wall
• DebugTextPlayer, optional, a TextMesh used for debug actions

The complete source code can be downloaded from GitHub (link).

Greetings @ Toronto

El Bruno

References

• GitHub, HoloToolkit
• GitHub, HoloToolkit Unity

El Bruno, my posts

• How to Import the HoloToolkit Unity
• How to place a Hologram using AirTap and HoloToolkit
• Creating a menu with options with HoloToolkit
• Using voice commands to display a menu with HoloToolkit
• How to create a 3D text always visible using HoloToolkit
• How to create a HUD (3D text always visible without HoloToolkit)
• How to detect hands using HoloToolkit
• Windows 10, Xbox One Controller, Bluetooth and some lessons learned
• How to use Fire Buttons actions with an XBoxOne Controller
• HoloToolkit compiled packages for Unity3D in GitHub
• How to detect AirTap and Click actions using HoloToolkit
• Detect user hand interactions using #HoloToolkit
• Moving and rotating Holograms using an XBoxOne Controller
• Spatial Understanding vs Spatial Mapping, and a tutorial on how to use them
• Spatial Mapping, tutorial to search for simple surfaces, like a 1×1 tile on the floor
• Alternative to fix the Tap to Place and World Anchor issue, until the official release of HoloToolkit for Visual Studio 2017 and Unity3D 5.6