PEXOCCSetFacetDistinguishFlag - Set Facet Distinguish Flag (5.0)

Synopsis

 
   void PEXOCCSetFacetDistinguishFlag(
        PEXOCC context,
        int flag
   )
 

   void PEXSetFacetDistinguishFlag(
        Display *display,
        XID resource_id,
        PEXOCRequestType req_type,
        int flag
   )
 

Arguments

context

An OC context returned by a successful PEXCreateOCC call.

display (OCC)

A pointer to a display structure returned by a successful XOpenDisplay call.

resource_id (OCC)

The resource identifier of the renderer or structure.

req_type (OCC)

The request type for the output command (PEXOCRender, PEXOCStore, PEXOCRenderSingle or PEXOCStoreSingle).

flag

The facet distinguish flag (True or False).

Returns

None.

Description

Invoke PEXOCCSetFacetDistinguishFlag to create an attribute output command which sets the facet distinguish flag attribute in the renderer's pipeline state according to the value specified by flag.

If you specify the facet distinguish flag as True, then the implementation applies back-facing surface attributes to back-facing facets, over-riding the corresponding surface attributes. If False, then the implementation applies surface attributes to both front-facing and back-facing facets.

A back-facing facet is defined if the geometric normal of a primitive facet has a non-negative z-component in normalized projection coordinates (NPCs).

If you do not specify True or False for the facet distinguish flag, then the implementation issues a BadPEXOutputCommand error.

This function is a member of the general surface attribute set.

Errors

BadPEXOutputCommand

The output command contains an invalid value.

BadPEXRenderer

The specified renderer resource identifier is invalid.

BadPEXStructure

The specified structure resource identifier is invalid.

See Also

For an overview and for a list of all output attribute functions, see Output Attribute Functions.