NAME

DoTranspOrientColor − Create a transparent color primitive attribute object for orientation dependent transparency

SYNOPSIS

C:

DtObject DoTranspOrientColor(colormodel, color)
DtColorModel colormodel;
DtReal color[];

FORTRAN:

INTEGER∗4 DOTOC(COLMOD, COLOR)
INTEGER∗4 COLMOD
REAL∗8 COLOR(∗)

DESCRIPTION

DoTranspOrientColor creates a transparent color primitive attribute object for orientation dependent transparency. 

Orientation dependent transparency means that the transparency of an object varies depending on the orientation of the object and the view direction.  The transparency can also vary across the object if it is not completely flat. 

The parameter color specifies the transparent color to be used for subsequent objects when the object is oriented such that the object normal is perpendicular to the viewing direction.  If the object normal is parallel to the viewing direction, the value defined by DoTranspColor is used as the transparent color.  For other object orientations the object transparent color is calculated as follows:

final transpcolor =
     orientcolor + (transpcolor - orientcolor)∗((I dot N) ∗∗ orientexp)

where orientcolor is the value specified by DoTranspOrientColor, transpcolor is the value specified by DoTranspColor, orientexp is the value specified by DoTranspOrientExp, N is the object normal, and I is the view direction (or the incoming ray direction for ray-tracing).  To enable orientation dependent transparency, both DoTranspOrientSwitch <DOTOS> and DoTranspSwitch <DOTS> must be turned on. 

DEFAULTS

The default DoTranspOrientColor is (DcRGB, 1.0,1.0,1.0.). 

SEE ALSO

DoTranspOrientSwitch(3D), DoTranspOrientIntens(3D), DoTranspOrientExp(3D), DoTranspIntens(3D), DoTranspColor(3D), DoTranspSwitch(3D)

September 02, 1992