NAME

DoTextureMapEnviron − Create an environment map primitive attribute object

SYNOPSIS

C:

DtObject DoTextureMapEnviron(operator, mapping, raster)
DtMapOperator operator;
DtObject mapping;
DtObject raster;

FORTRAN:

INTEGER∗4 DOTME(OPRATR, MAPPNG, RASTER)
INTEGER∗4 OPRATR
INTEGER∗4 MAPPNG
INTEGER∗4 RASTER

DESCRIPTION

DoTextureMapEnviron creates a primitive attribute object that specifies an environment map. 

A primitive object can be affected by more than one DoTextureMapEnviron attribute.  The parameter operator specifies whether subsequent primitive objects will be affected by this environment map only, or also by other environment maps higher up in the scene hierarchy.  The possible values for operator are:

DcMapReplace <DCMR>
Any environment maps already defined will be ignored by subsequent primitive objects.

DcMapAdd <DCMADD>
Use this map in addition to the environment maps higher up in the hierarchy. The map that is defined closest to the primitive object will be evaluated first. Note that a primitive object can only be affected by textures above it in the hierarchy.

The parameter mapping specifies which mapping procedure to use.  Possible values for mapping are:

DcStdSphereEnvironMap <DCSSEM>
Use the default spherical environment mapping method the renderer provides.

DcStdCubeEnvironMap <DCSCEM>
Use the default cubic environment mapping method the renderer provides.

Renderer-specific mappings
Use any renderer-specific mappings documented in your Doré System Guide. 

The parameter raster contains the actual environment map data to be used by the texturing procedure.  raster is a handle to an object created with DoRaster <DORS> or DoFileRaster <DOFRS>.  The number of channels of data used for the environment mapping depends on the colormodel.  Three channels are required if the RGB colormodel is used.  If the raster data is in the standard Doré format, the following convention is used.  For rasters of type DcRasterRGB <DCRRGB>, DcRasterRGBA <DCRRA>, DcRasterRGBZ <DCRRZ> and DcRasterRGBAZ <DCRRAZ> the RGB channels are used.  Rasters of type DcRasterA <DCRA> and DcRasterZ <DCRZ> cannot be used as environment maps in conjunction with the RGB colormodel. 

DoTextureMapEnviron is a primitive attribute and is inherited by subsequent primitive objects, as are all primitive attributes.  Unlike most other primitive attributes though, DoTextureMapEnviron also inherits a set of attributes, i.e. the texture attributes. 

The texture attributes specify things such as which set of primitive uv coordinates to use, how to extend a texture when the primitive uv coordinates extend beyond the limits of the texture, how to transform the primitive uv coordinates before applying the texture, etc.  The current values of the texture attributes are bound to the DoTextureMapEnviron object when it is executed during traversal.  Thus the texture attributes are only indirectly bound to the primitive objects. 

SEE ALSO

DoDiffuseColor(3D), DoFileRaster(3D), DoRaster(3D), DoTextureAntiAlias(3D), DoTextureExtendUV(3D), DoTextureExtendUVW(3D), DoTextureMapEnvironSwitch(3D), DoTextureMatrixUV(3D), DoTextureMatrixUVW(3D), DoTextureScaleUV(3D), DoTextureScaleUVW(3D), DoTextureTranslateUV(3D), DoTextureTranslateUVW(3D), DoTextureUVIndex(3D), DoTextureUVWIndex(3D)

September 02, 1992