PSBISM(3g) — Subroutines

Name

PSBISM − Specifies the back interior shading method for displaying back-facing portions of area primitives.

Operating States: PHOP, ∗, STOP, ∗
PHIGS PLUS function
Creates a structure element

Old Syntax

DSBISM (SHDMD)

Argument Data Type Access Description
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SHDMD Integer Read Back interior shading method
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New Syntax

PSBISM (ISM)

Argument Data Type Access Description
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ISM Integer Read Back interior shading method
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Constants

Defined Argument      Constant      Description
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ISM                   PNOIS         No interpolation, constant shading
                      PCIS          Linear interpolation of color
                      PDDIS         Interpolation of color based on dot
                                    products
                      PDNIS         Interpolation of color based on
                                    normals
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Description

PSBISM specifies the back interior shading method Digital PHIGS uses to display back-facing portions of area primitives. Depending on the edit mode, this function either inserts the new structure element directly after the pointer or replaces the element indicated by the pointer. The pointer then points to the new set back interior shading method element.

During structure traversal, Digital PHIGS sets the current back interior shading method entry in the PHIGS traversal state list to the value associated with the element. When the current back interior shading method ASF entry in the state list is INDIVIDUAL, Digital PHIGS uses this value to display subsequent back-facing portions of area primitives. If the specified interior shading method is not available on a workstation, Digital PHIGS uses interior shading method 1.

If Digital PHIGS is in immediate mode, it performs this function immediately, but the function does not create a structure element.

The new function syntax conforms to the ISO Fortran standard. Digital recommends that you code using the new function syntax.