Animated Wall Cracks

This post currently has placeholder images and videos. I’m just waiting on the green light from PlaySide to include the actual media I’d like to share.

During early prototyping of Shattered (Unity - Quest 3 Mixed Reality), we experimented with placing cracks on the player’s wall that would open up with water gushing in, eventually filling the player’s room.

I created some cracks in Blender and used Shape Keys to animate them opening. In the image below, the front-facing polygons are set to blue and the back-facing polygons to red.

Here’s an example of a test crack opening from top to bottom using Shape Keys.

To ensure that the front-facing polygons were only visible through the opening and hidden when the crack was closed, I created stencil mask meshes.

The stencil masks also needed Shape Keys to animate in sync with the cracks.

In this example, we have the crack mesh in a new scene. It disappears once we rotate it far enough that we can no longer see through the stencil mask.

And here’s the final result in a new scene. When the stencil mask is closed, the crack’s front-facing polygons are completely hidden.