Creating with Vircadia

For the time being, content/models are created externally in software packages like Blender and positioned in 3D space using the Native Developer Client.

note

Objects using draco compression will not be rendered in the Native Developer Client but can still be positioned by selecting them in the entity list.

Asset Creation

For best performance:

• Use less materials by combining textures when applicable
• Combine model clusters to lower the mesh count
• Consider using instances (linked duplicates in Blender) for repeat assets placed far from each other, but keep in mind a large number of objects in a scene will burden the CPU.
• Use multiple levels of detail (LOD) to lower polygon count

note

When using instances and LOD together, be sure to duplicate only LOD0 when placing throughout the scene, otherwise additional meshes will be created and stacked.

Model Types

Vircadia officially supports glTF 2.0 models.

• Binary (.glb): A single file making it efficient and easy for sharing, with one network request needed.

• Separate (.gltf, .bin, + textures): Multiple files requiring multiple network requests, useful if several models share resources like textures.

• Embedded (.gltf): One file with a Data URI payload, making it easy to edit manually, but increases file size by 20-30%. This format is not typically preferred over the Binary format.

For most puproses a .glb file is adequate, however if you wish to re-use textures and materials in other projects and enviroments you may decide to use the second option, though this is more complicated.

LOD

Take advantage of LOD (by appending the following suffixes to your meshes' name:

• _LOD0 required, highest detail
• _LOD1
• _LOD2
• _LOD3
• _LOD4 lowest detail

LODs are a great way to lower the onscreen polygon count as objects get farther from the camera. This is done by switching to simplified models at a specified distance or size. While this does increase the filesize somewhat, this can be mitigated by using draco compression.

note

You can use as few LODs as you like, or none at all, but keep in mind certain properties require LOD0 at minimum, such as vircadia_lod_hide.

Draco Compression

Draco Compression shrinks the size of 3D models and make them faster to share or download, without obvious visual quality loss. This can typically be enabled during the GLTF export process in your 3D editor.

Properties

In your glTF extras properties, use the properties to configure LOD settings, overriding the defaults.

For more information on how our LOD works, see Babylon.js' documentation on LOD. In Blender, add these properties in the "Object" tab under "Custom Properties."

Automatic Generation

Property vircadia_lod_auto:

• true
• false default

Mode

Property vircadia_lod_mode:

• distance default
• size

Distance mode switches between objects based on their distance from the camera Size mode switches between object depending their size on screen. As a natural result larger objects will maintain their detail at a greater distance.

Distance

Property vircadia_lod_distance:

• 0 to 100000 in meters.

Default

LOD	Distance
LOD0	0
LOD1	15
LOD2	30
LOD3	60
LOD4	120

Size

Property vircadia_lod_size:

• 0.01 to 1.0

Default

...

Billboard

Property vircadia_billboard_mode:

• x, y, z, all or none default

With billboarding an object will always face the specified direction. This is especially useful on low detail LODs to create a "cardboard cutout" that always faces the camera. This is often used on the highest numbered LOD on trees and other foliage, but is not required.

Hide

property vircadia_lod_hide

• 0 to 100000 in meters.

Specifies the distance at which the object is culled completely (optional).

note

This property must be added to LOD0 to take effect.

Collisions

It is highly recommended to make your own simplified collision meshes rather than using the fully detailed models, as this uses significant computing power. Collisions can be enable/disabled on a model via the Collision tab of the Properties panel within the Create Tools of the Native Developer Client.

note

Remember to "hide" your collision mesh to keep it from being rendered.

Asset Hosting

Configuring CORS on your hosting provider enables assets to be loaded into the world from URLs that are not on the same domain as the web client.

1. CORS on AWS S3 - Cloud