BackgroundFade

Synopsis

The BackgroundFade macro creates a DataObject that can be used as a static sky gradient background to a 3D Viewer window with an interpolated fade based on 4 RGB values at each corner.

Input Port

none.

 

Parameters

depth

float

Distance background is from camera.

None

Upper_Left_Red

Upper_Left_Green

Upper_Left_Blue

float

RGB values for upper left corner of image.

UIslider

Upper_Right_Red

Upper_Right_Green

Upper_Right_Blue

float

RGB values for upper right corner of image.

UIslider

Lower_Left_Red

Lower_Left_Green

Lower_Left_Blue

float

RGB values for lower left corner of image.

UIslider

Lower_Right_Red

Lower_Right_Green

Lower_Right_Blue

float

RGB values for lower right corner of image.

UIslider

Output Port

out_fld

Mesh+Node_Data

Field containing Quad cell-set that is used as background.

out_obj

GDobject

Directly renderable output object.

Description

The BackgroundFade macro creates a DataObject that can be used as the background to a Viewer window. The controls allow the user to specify a colour fade across the background of the viewer. This allows scenes to contain a simulated sky backdrop.

The effect of a static viewer window background is produced by creating a field that contains a single square cell-set. This cell-set is sized so that it covers the viewer window and is slightly in front of the far clipping plane. The far clipping plane specifies the maximum distance that an object can be away from the camera before it is ignored. Therefore by placing the background slightly in front of the far clipping plane it should be behind everything else. The field is then placed into a DataObject and the transformation of the DataObject is locked. This ensures that the background is not transformed with the rest of the scene.

The background image is created by using node data. The BackgroundFade macro creates a set of node data with a triplet of RGB values at each corner of the square. AVS/Express interpolates between each of these RGB values as normal to create the colour fade effect that can be seen.

Example

Not available

File

v/geoms.v

See also related modules