NAME

POLYMARKER − create structure element specifying 2D polymarker primitive

SYNOPSIS

C Syntax

void
ppolymarker ( point_list )
Ppoint_list∗point_list;list of points

Required PHIGS Operating States

(PHOP, ∗, STOP, ∗)

DESCRIPTION

Purpose

The POLYMARKER function puts the full specification of a POLYMARKER primitive into the currently open structure.  A POLYMARKER primitive is a series of markers, such as dots, plus signs, asterisks, circles, or x’s, drawn in the display at specified Modelling Coordinate (MC) points on the z = 0 plane. 

C Input Parameters

point_list
A pointer to a Ppoint_list structure containing a list of Ppoint structures, which contain the x and y coordinates for each point at which markers will be placed. 

The Ppoint_list structure is defined in phigs.h as follows:

typedef struct  {
Pintnum_points;/∗ number of Ppoint elements in the list ∗/
Ppoint∗points;/∗ list of points ∗/
} Ppoint_list;

The num_points component specifies the number of elements in the list.  The points component is a pointer to a list of Ppoints num_points long.  The Ppoint structure is defined in phigs.h as follows:

typedef struct  {
Pfloatx;/∗ x coordinate ∗/
Pfloaty;/∗ y coordinate ∗/
} Ppoint;

Execution

If the current edit mode is INSERT, the POLYMARKER element is inserted in the open structure after the element pointed at by element pointer. If the current edit mode is REPLACE, the POLYMARKER element replaces the element pointed to by the element pointer.  In either case, the element pointer is updated to point to the new POLYMARKER element. 

When the structure is traversed, the POLYMARKER element places a marker at each of the coordinate locations specified. The current values of the attributes listed below will be applied to the marker. 

The coordinates used to specify the polymarker primitive are MCs.  These may be any coordinate units that are convenient to the application. At traversal, these coordinate values are transformed by the current local and global modelling transformations, the view representation selected by the current view index, and the workstation transformation current on the workstation to which the structure is posted. 

Attributes Applied

The attributes listed below are used to display the POLYMARKER primitive when the structure is traversed. The Aspect Source Flags (ASFs) tell where to access the output display attributes.  These attributes can come directly from the traversal state list, or they can be accessed indirectly, using the appropriate index in the traversal state list and the corresponding bundled representation in the PHIGS workstation state list. 

marker typemarker type ASF
marker size scale factormarker size scale factor ASF
polymarker colourpolymarker colour index ASF
polymarker index
depth cue index
name set

ERRORS

005Ignoring function, function requires state (PHOP, ∗, STOP, ∗)

SEE ALSO

INQUIRE POLYMARKER FACILITIES (3P)
POLYMARKER 3 (3P)

September 02, 1992