This page details how to control the global settings of VIVERSE Polygon Streaming within your Unreal project.
The Stream Controller manages the streaming of models and streaming parameters inside your project. There must be only one Stream Controller per scene, since it will control all Streaming Models as one.
The Triangle Budget is a limit on the amount of triangles that will be drawn per frame. Increasing this will lead to better visual quality, but of course also higher processing and memory utilization. It's recommended to keep Triangle Budget to at least 30% of the full amount of polygons that you are going to stream. For example, if you are going to stream a 3D model of 10 million polygons, it's recommended to use a Triangle Budget of at least 3 million.
In case you use too low Triangle Budget, for example 500 thousand to stream 10 million polygons, you may reach the budget before it's possible to showcase the higher quality of the model. Resulting in only showing a lower quality version of the model in order to stay within the budget.
The Distance Factor is a factor between the distance of the camera to the object being streamed. The default value of 1.1 has a neutral preference. A higher value, such as 3 or 5, will have a preference for nearby objects over objects further away. These parameters can be changed at runtime to find the sweet spot for your scene.
The Distance Type can be set to Bounding Box or Bounding Box Center. In case it's set to Bounding Box it will calculate the distance between the camera and object based on the edges of the bounding box of the object. In case it's set to Bounding Box Center, it will calculate the distance from the center of the object. It's recommended to use Bounding Box for single objects, and Bounding Box Center for full environments in which the user will be walking inside the object.
The Close Up Distance is a change in the distance factor between camera and streaming object when the camera gets too close. For example, when the camera is at 3 units or less of distance from the object, it will use the value at Close Up Distance Factor, when the camera is further than 3 units from the object, it will use the value at Distance Factor. That way the system forces a strong streaming of data when the camera is very close to an object.
The other parameters should be left in default or you can check an explanation on the Supported Parameters section.
Triangle Budget
The maximum amount of triangles that you want to allow in the scene at any single point.
3000000
Distance Factor
Preference for nearby objects over objects further away. Values above one mean a preference for nearby objects. Values below one mean a preference for objects further away. One is neutral.
1.1
Distance Type
Distance type from camera to the meshes bounding boxes.
Bounding Box
Close Up Distance
The distance where it starts using Close-up Distance Factor instead of Distance Factor. Set it to 0 to not use close-up distance factor.
3
Close Up Distance Factor
The distance factor used when close-up to an object. Should be higher than the standard Distance Factor.
5
Maximum Quality
Stops improving geometry that exceeds the maximum quality. This can be used to stop far away objects from showing more detail which can be wasteful. Leaving this at 0 means there is no maximum quality.
3000000