Overview
Default Cube does give a few world-navigation helpers, but does not come with an actual physics engine. You are free to integrate any engine compatible with Three.js though.
Navmeshes
You can limit the walkable area of every scene using navmeshes. When, for example, a character is moving around - PhysicsService will the check whether the character is within the allowed area. This allows you to easily create floors, walls, and doors.
Note: Navmeshes can be dynamically enabled and disabled using the PhysicsService.
const hero = myHeroModel;
// NOTE Enable physics for the model using a PhysicsWrapper
const heroPhysics = new PhysicsWrapper(hero);
heroPhysics.enableNavmaps();
Navmaps can be declared directly within the Blender file using a custom property (it requires no value):
navmap: []
Hit-testing
To determine collisions between two meshes, you can use PhysicsService.registerDynamicCollisionBody:
PhysicsService.registerDynamicCollisionBody(hero, (hitObject) => {
if (hitObject instanceof Enemy) {
// NOTE Game logic
}
});
Surfaces
PhysicsService allows you to also register trigger surfaces - think of it as an extension of the navmaps idea.
Registered surface reacts to being stepped on, for example snow caving in. To setup a surface type, you need to first define the behaviour in code:
class SampleSufrace {
onInteraction(threeJsCollision) {
console.info('Surface reached', { threeJsCollision });
}
}
PhysicsService.registerSurfaceHandler('snow', SampleSufrace, 'onInteraction');
Then, in the Blender file, you can assign the surface type to specific meshes:
surface: [surfaceId]
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