PHIGS TRAVERSAL STATE LIST(7P) — Kubota Pacfic Computer Inc. (29 February 1991)
NAME
PHIGS TRAVERSAL STATE LIST − contains all transient information PEX-SI uses during traversal
DESCRIPTION
The PHIGS Traversal State List is created whenever a traversal is initiated, and only exists during the traversal. Hence, its values cannot be inquired. Traversal is the execution of a structure network. Traversal begins with a structure posted to a workstation. Structure elements are traversed sequentially. The traversal state list is modified by executing attribute elements.
The initial values in the traversal state list are either defined by the PHIGS standard, or are implementation dependent. These values are inherited by a posted structure. Whenever an EXECUTE STRUCTURE element is traversed, the executed structure, or child structure, inherits the attributes of the parent structure; that is, the structure invoking (executing or referencing) it. Different parent structures can assign different attribute values.
The child structure’s attributes are then modified by attribute elements as they are sequentially executed. The child structure may also execute subordinate structures, at which point the calling structure is considered the parent of this generation. At the end of the child structure (i.e., after its last element), traversal returns to the parent structure, restoring the saved state of the parent structure, and continues until the end of the parent structure. This continues until the entire structure network is traversed (i.e., until traversal of the posted structure is complete). The modifications to the child’s structure do not affect the parent structure’s attributes. Traversal state list values may be said to expire at the end of the structure in which they are set, as traversal of the parent structure resumes.
The values in the traversal state list are bound to primitives as the primitive elements are sequentially executed.
Data Type Abbreviations
IIntegerGCOLRGeneral Colour†
RRealV2/V32D/3D Vector
EEnumeration TypeP33D Point
L(type)List of values of a given type SET(NM) Set of Eligible Names
MCVModelling Clipping Volume(nys)Not Yet Supported
PEX-SI Traversal State List
| Traversal State List Entry | Data Type | Default or Initial Value |
| polyline index | I | 1 |
| linetype | I | 1 |
| linewidth scale factor | R | 1.0 |
| polyline colour index | I | 1 |
| polyline colour† | GCOLR | (INDIRECT,1) |
| linetype ASF | E | INDIVIDUAL |
| linewidth scale factor ASF | E | INDIVIDUAL |
| polyline colour index ASF | E | INDIVIDUAL |
| polyline shading method† | I | 1 (NONE) |
| curve approximation criteria type† | I | 1 (Workstation Dependent) |
| curve approximation criteria value† | R | 1.0 |
| polyline shading method ASF† | E | INDIVIDUAL |
| curve approximation criteria ASF† | E | INDIVIDUAL |
† This is a PHIGS Extension based on PHIGS PLUS and is not a part of the PHIGS standard.
PHIGS Traversal State List (continued)
| Traversal State List Entry | Data Type | Default or Initial Value |
| polymarker index | I | 1 |
| marker type | I | 3 |
| marker size scale factor | R | 1.0 |
| polymarker colour index | I | 1 |
| polymarker colour† | GCOLR | (INDIRECT,1) |
| marker type ASF | E | INDIVIDUAL |
| marker scale factor ASF | E | INDIVIDUAL |
| polymarker colour index ASF | E | INDIVIDUAL |
| text index | I | 1 |
| text font | I | 1 (Monospaced Roman Simplex) |
| text precision | E | STRING |
| character expansion factor | R | 1.0 |
| character spacing | R | 0.0 |
| text colour index | I | 1 |
| text colour† | GCOLR | (INDIRECT,1) |
| text font ASF | E | INDIVIDUAL |
| text precision ASF | E | INDIVIDUAL |
| character expansion factor ASF | E | INDIVIDUAL |
| character spacing ASF | E | INDIVIDUAL |
| text colour index ASF | E | INDIVIDUAL |
| character height | R | 0.01 |
| character up vector | V2 | (0.0,1.0) |
| character width | R | 0.01 |
| character base vector | V2 | (1.0,0.0) |
| text path | E | RIGHT |
| text alignment (horz & vert) | 2×E | (NORMAL,NORMAL) |
| annotation text character height | R | 0.01 |
| annotation text character up vector | V2 | (0.0,1.0) |
| annotation text character width | R | 0.01 |
| annotation text character base vector | V2 | (1.0,0.0) |
| annotation text path | E | RIGHT |
| annotation text alignment (horz & vert) | 2×E | (NORMAL,NORMAL) |
| annotation style | I | 1 (unconnected) |
† This is a PHIGS Extension based on PHIGS PLUS and is not a part of the PHIGS standard.
PHIGS Traversal State List (continued)
| Traversal State List Entry | Data Type | Default or Initial Value |
| interior index | I | 1 |
| interior style | E | HOLLOW |
| back interior style† | E | HOLLOW |
| interior style index | I | 1 |
| back interior style index† | I | 1 |
| interior colour index | I | 1 |
| interior colour† | GCOLR | (INDIRECT,1) |
| back interior colour† | GCOLR | (INDIRECT,1) |
| interior style ASF | E | INDIVIDUAL |
| back interior style ASF† | E | INDIVIDUAL |
| interior style index ASF | E | INDIVIDUAL |
| back interior style index ASF† | E | INDIVIDUAL |
| interior colour index ASF | E | INDIVIDUAL |
| back interior colour ASF† | E | INDIVIDUAL |
| ambient reflection coefficient† | R | 1.0 |
| back ambient reflection coefficient† | R | 1.0 |
| diffuse reflection coefficient† | R | 1.0 |
| back diffuse reflection coefficient† | R | 1.0 |
| specular reflection coefficient† | R | 1.0 |
| back specular reflection coefficient† | R | 1.0 |
| specular colour† | GCOLR | (INDIRECT,1) |
| back specular colour† | GCOLR | (INDIRECT,1) |
| specular exponent† | R | 0.0 |
| back specular exponent† | R | 0.0 |
| interior shading method† | I | 1 (NONE) |
| back interior shading method† | I | 1 (NONE) |
| interior reflectance equation† | I | 1 (NONE) |
| back interior reflectance equation† | I | 1 (NONE) |
| area properties ASF† | E | INDIVIDUAL |
| back area properties ASF† | E | INDIVIDUAL |
| interior shading method ASF† | E | INDIVIDUAL |
| back interior shading method ASF† | E | INDIVIDUAL |
| interior reflectance equation ASF† | E | INDIVIDUAL |
| back interior reflectance equation ASF† | E | INDIVIDUAL |
| surface approximation criteria type† | I | 1 (Workstation Dependent) |
| surface approximation criteria value† | 2×R | (1.0,1.0) |
| surface approximation criteria ASF† | E | INDIVIDUAL |
| face distinguishing mode† | E | NO |
| face culling mode† | E | NONE |
† This is a PHIGS Extension based on PHIGS PLUS and is not a part of the PHIGS standard.
PHIGS Traversal State List (continued)
| Traversal State List Entry | Data Type | Default or Initial Value |
| depth cue index† | I | 0 |
| colour mapping index† | I | 0 |
| rendering colour model† | I | 0 |
| light source state† | L(I) | empty |
| edge index | I | 1 |
| edge flag | E | OFF |
| edgetype | I | 1 |
| edgewidth scale factor | R | 1.0 |
| edge colour index | I | 1 |
| edge colour† | GCOLR | (INDIRECT,1) |
| edge flag ASF | E | INDIVIDUAL |
| edgetype ASF | E | INDIVIDUAL |
| edgewidth scale factor ASF | E | INDIVIDUAL |
| edge colour index ASF | E | INDIVIDUAL |
| pattern size | 2×R | (1.0,1.0) |
| pattern reference point | P3 | (0.0,0.0,0.0) |
| pattern reference vectors | 2×V3 | (1.0,0.0,0.0) (0.0,1.0,0.0) |
| pick identifier | I | 0 |
| view index | I | 0 |
| HLHSR identifier | I | 0 |
| name set | SET(NM) | no classes (empty set) |
| global modelling transformation | 4×4×R | Identity |
| local modelling transformation | 4×4×R | Identity |
| modelling clipping volume | MCV | all of WC |
| modelling clipping indicator | E | NOCLIP |
† This is a PHIGS Extension based on PHIGS PLUS and is not a part of the PHIGS standard.
‡ This is a PHIGS-specific item of traversal state. See the appropriate GSE man page.
∗ Zero is workstation dependent.
SEE ALSO
PHIGS DESCRIPTION TABLE (7P)
EXECUTE STRUCTURE (3P)
INQUIRE ANCESTORS OF STRUCTURE (3P)
INQUIRE DESCENDANTS OF STRUCTURE (3P)
ELEMENT SEARCH (3P)
September 02, 1992