Billboards: BillboardsThursday, December 19, 2013 8:37 PM
Billboards are geometry quads which usually are always facing the camera. Paradise Sandbox's billboards are very versatile since you are able to easily choose the orientation behaviour, texture and color blend type.
You can change the billboard size by using the scale gizmo (hotkey: 'H'). Paradise Sandbox will also resize the billboard to match the relation aspect of the selected texture, although your able to change only the width or height using the proper scale gizmos:
The following parameters control the billboard orientation:
- Face to camera: Specifies if the billboard must to be oriented to the camera or, alternatively, be treated as a simple quad which can be rotated using the transform gizmos
- Use fixed axis: If 'Face to camera' is enabled, optionally you can select a rotation axis. This is very usefull for certain types of billboards: for example, people and trees will usually use the Y axis as rotation axis (default behaviour)
- Fixed axis: If 'Use fixed axis' is checked, this specifies the axis to be used as rotation axis
Here is a visual comparison:
- Opaque: Default and preferred: the billboard will not have semi-transparent parts (or fully transparent or fully solid), but instead you will have correct physically-based lighting and also ambient occlusion.
- Add: The color will be added to the color from the scene. This is perfect for effech such as fire or light glares.
- Alpha: The color will be alpha-blended with the color of the scene, for effects such as dust. This is only recomended for open-door scenes (without much point lights or spotlights).
By default, billboards don't cast shadows since there is not a correct way for defining billboard shadows when them are always oriented to the camera. This is caused because of the shadow casted by the billboard must to be always the same regardless of the camera's position, but when you're looking to the billboard from the oposite side you will see that the casted shadow is inverted.
For non oriented billboards ('Face to camera' disabled), shadows makes perfectly sense and, if enable, you will not experiment any strange behaviour like you will with oriented billboards.