Version 5 (modified by martin, 7 years ago)

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OSG BillBoard

General

The Billboard Helper comes as part of the OSG Exporter-plugin for 3d Studio MAX. It can be used to enhance scenes for usage in a Virtual Reality-environment. A Billboard is an object which displays the same image nomatter from which direction you are looking at it. It gives the illusion of being a 3D object, but is in fact 'only' 2D. These objects can e.g. be used to place trees in your scene. You should use Billboards to lower the size of the scene. Billboards use considerably less calculation time then geometry.

The modfiy panel options for the Billboard Helper

To create a Billboard in MAX

  • Create a plane object and assign mapping coordinates to it
  • Create a new material, using the bitmap you want to use as your Billboard as the Diffuse Color map;
  • Assign this material to the plane object
  • Create an OSG Billboard Helper;
  • In the Modify panel: pick 'Add' in Billboard Geometry and select the Plane. This now functions as a Billboard when the scene is exported to OSG/IVE-format.

Other options

  1. Mode: this defines the rotational behavious of the Billboard. Axial Rot(ation) makes it rotate arount an axis (defined in Axis), Point Rot World and Point Rot Eye both let the Billboard rotate around a single point, but the first relative to World coordinates, the second relative to Eye position . Use the Axial rotation if you want to create trees in your scene.
  2. Axis: The amount the Billboard rotates around every axis. For trees in an architectural or urban setting pick the Z-axis.
  3. Normal: Sets the direction of the normal and can also be used to influence the behaviour. Leave at the default for trees.

Demonstration

The pictures show that the Billboard is always facing the viewpoint, rotating itself around the defined axis. This Billboard was created with the default settings (as shown in the Options panel on this page). You can download the demo scene. The .MAX, .OSG and bitmaps used are included in the archive.

More information

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