pquad_mesh_data(3g) — Subroutines

Name

pquad_mesh_data − Specifies the surface and interior attributes of a 2D quadrilateral mesh.

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

Syntax

void pquad_mesh_data (
Pint                     colr_type,   /∗ (I) Color type ∗/
const Pfacet_array      ∗facet_data, /∗ (I) Array of facet data ∗/
const Pedge_flag_array ∗edge_flags, /∗ (I) Array of edge flags ∗/
const Pvertex_array     ∗vertex_data /∗ (I) Array of vertex data ∗/
)

Data Structures

typedef struct {
    Pint_size    dims;                  /∗ facet array dimensions ∗/
    Pint         num_data_per_facet;    /∗ number of data values per
                                           facet ∗/
    Pcolrv_ptr ∗facet_colrvs;          /∗ array of facet colors ∗/
    Pvec3       ∗facet_norms;           /∗ array of facet normals ∗/
    Pfloat      ∗facet_data;            /∗ list of facet data lists ∗/
} Pfacet_array;
    typedef struct {
        Pint    size_x;    /∗ x size ∗/
        Pint    size_y;    /∗ y size ∗/
    } Pint_size;
    typedef union {
        Pint           ∗colr_inds; /∗ pointer to color indexes ∗/
        Pcolr_rep_ptr   colr_reps; /∗ pointer to color representations ∗/
    } Pcolrv_ptr;
        typedef union {
            Prgb       ∗rgb;       /∗ pointer to RGB color values ∗/
            Pcieluv    ∗cieluv;    /∗ pointer to CIELUV color values ∗/
            Phls       ∗hls;       /∗ pointer to HLS color values ∗/
            Phsv       ∗hsv;       /∗ pointer to HSV color values ∗/
            Pdata      ∗unsupp;    /∗ pointer to unsupported color
                                      values ∗/
        } Pcolr_rep_ptr;
            typedef struct {
                Pfloat   red;     /∗ red intensity   ∗/
                Pfloat   green;   /∗ green intensity ∗/
                Pfloat   blue;    /∗ blue intensity ∗/
            } Prgb;
            typedef struct {
                Pfloat   cieluv_x;      /∗ x coefficient ∗/
                Pfloat   cieluv_y;      /∗ y coefficient ∗/
                Pfloat   cieluv_y_lum; /∗ y luminance ∗/
            } Pcieluv;
            typedef struct {
                Pfloat   hue;        /∗ hue ∗/
                Pfloat   lightness; /∗ lightness ∗/
                Pfloat   satur;      /∗ saturation ∗/
            } Phls;
            typedef struct {
                Pfloat   hue;    /∗ hue ∗/
                Pfloat   satur; /∗ saturation ∗/
                Pfloat   value; /∗ value ∗/
            } Phsv;
            typedef struct {
                size_t   size;   /∗ size of data ∗/
                void    ∗data;   /∗ pointer to the data ∗/
            } Pdata;
    typedef struct {
        Pfloat    delta_x;    /∗ delta x value ∗/
        Pfloat    delta_y;    /∗ delta y value ∗/
        Pfloat    delta_z;    /∗ delta z value ∗/
    } Pvec3;
typedef struct {
    Pint_size            dims;         /∗ edge flag array dimensions ∗/
    Pedge_flag_pair     ∗edge_flags;   /∗ array of edge flag pairs ∗/
} Pedge_flag_array;
    typedef Pedge_flag Pedge_flag_pair[2];
        typedef enum {
            PEDGE_OFF,   /∗ edges off ∗/
            PEDGE_ON     /∗ edges on ∗/
        } Pedge_flag;
typedef struct {
    Pint_size      dims;                  /∗ dimensions of vertex array ∗/
    Pint           num_data_per_vertex;   /∗ number of data values per
                                             vertex ∗/
    Ppoint        ∗vertex_points;         /∗ array of vertex points ∗/
    Pcolrv_ptr     vertex_colrvs;         /∗ array of vertex colors ∗/
    Pvec3         ∗vertex_norms;          /∗ array of vertex normals ∗/
    Pfloat        ∗vertex_data;           /∗ array of vertex data lists ∗/
} Pvertex_array;
    typedef struct {
        Pfloat     x;    /∗ x coordinate ∗/
        Pfloat     y;    /∗ y coordinate ∗/
    } Ppoint;
    typedef union {
        Pint           ∗colr_inds; /∗ pointer to color indexes ∗/
        Pcolr_rep_ptr   colr_reps; /∗ pointer to color representations ∗/
    } Pcolrv_ptr;
        typedef union {
            Prgb       ∗rgb;       /∗ pointer to RGB color values ∗/
            Pcieluv    ∗cieluv;    /∗ pointer to CIELUV color values ∗/
            Phls       ∗hls;       /∗ pointer to HLS color values ∗/
            Phsv       ∗hsv;       /∗ pointer to HSV color values ∗/
            Pdata      ∗unsupp;    /∗ pointer to unsupported color
                                      values ∗/
        } Pcolr_rep_ptr;

Constants

Defined Argument      Constant           Description
---------------------------------------------------------------------------
colr_type             PCOLR_INDIRECT     Indirect (indexed) color
                      PCOLR_RGB          Direct specification of red,
                                         green, and blue
                      PCOLR_CIELUV       Direct specification in the format
                                         of the Commission Internationale
                                         de l’Eclairage
                      PCOLR_HSV          Direct specification of hue,
                                         saturation, and value
                      PCOLR_HLS          Direct specification of hue,
                                         lightness, and saturation
---------------------------------------------------------------------------

Description

pquad_mesh_data specifies the surface and the interior attributes of a two-dimensional quadrilateral mesh. The quadrilateral mesh surface is composed of a point array. Digital PHIGS then connects the vertices to create a single facet.

If the data per facet flag indicates that you have specified a facet color, or if the data per vertex flag indicates that you have specified vertex colors, you must also have specified a color type.

The vertex data is a two-dimensional array (of mxn) where the data in each set of four neighboring array elements defines a quadrilateral, which need not be planar. Digital PHIGS uses a workstation-dependent method to render, decompose, or both, the quadrilateral mesh. Digital PHIGS considers a mesh with n < 2 or m < 2 degenerate, and treats it in an implementation-dependent manner.

During structure traversal, Digital PHIGS draws a two-dimensional mesh of (n--1) x (m--1) quadrilaterals, using the same set of attributes used for the fill area set with data primitive.

Depending on the edit mode, this function either inserts the new structure element directly after the element indicated by the pointer or replaces the element indicated by the pointer. The pointer then points to the new quadrilateral mesh with data element.

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

You can pass a null value for the facet_data or edge_flags arguments because that data is optional. Two-dimensional arrays must have row-major format.

Digital PHIGS Version 4.1 does not support this function.