UI Mask not working on HoloLens
I am working on a custom slider control and have used a UI Mask to give the slider a gauge like appearance.
The mask seems to work fine and display correctly in the Game view in Unity:
But when I run the project in the emulator or on the device the mask does not seem to work:
Here is an example from one of the controls of the Inspector view of the mask:
To create the mask itself I started with a png that has transparency in the areas that should be masked and some color value in the areas that the control should show through (the arc shape). After adding the png to my unity project I then change the Texture Type to Sprite (2D and UI) and assign that sprite to the source image of the image element that has the mask.
The mask png basically looks like this:
Originally I used black as the color value and my first thought was that the HoloLens treats black in a special way in certain contexts, so I changed my png to use the color green instead but got the same results.
Is this a HoloLens bug?
Are masks just not supported on HoloLens?
(if not, then please consider this a feature request)
Or am I doing something wrong and if so what might that be?