GPPGD2
(pflags,
pdata,
saflags,
sawidth,
sadata,
vxflags,
vxwidth,
vxdata) |

**Purpose**

Use **GPPGD2** to insert a Polygon 2 With Data
structure element into the open structure following the
element pointer or to replace the element pointed at by the
element pointer with a Polygon 2 With Data structure element
depending on the current edit mode.

When encountered during structure traversal, this element generates a polygon with the specified number of subareas. You may specify optional data to further control the rendering of this primitive. The optional data consists of:

The convexity flag indicates that the application
determined the convexity of the polygon primitive.
Therefore, the system rendering code does not have to
determine the convexity every time the primitive is
rendered.
To determine the convexity of a set of polygons, the graPHIGS API
on the RISC System/6000 contains a sample program under the
AIX (*) directory:
**/usr/lpp/graPHIGS/samples/convexcheck**

When rendering this primitive, if the primitive is not to be highlighted, then the graPHIGS API uses the specified vertex color. The colors are used in the lighting process to produce more realistic effects.

When rendering this primitive, if the current edge flag
attribute is set to
`2=ON`
, then the graPHIGS API
renders as part of the edge, only the parts of the polygon
defined by the boundary flags to be part of the edge.
If there are no boundary flags specified, then the graPHIGS API
treats it the same as a polygon
(i.e. all boundaries are rendered as edges)

You can specify a transparency coefficient per vertex. The graPHIGS API uses these values when producing transparency effects for the rendered primitive.

You can supply vertex morphing vectors per vertex.
The graPHIGS API combines these vectors with the vertices and
vertex morphing scale factors
(**GPVMF**)
to create new vertex coordinate values for the rendered primitive.

You can specify data mapping data per vertex. The graPHIGS API uses these values to determine the colors of the rendered primitive.

You can specify data morphing vectors per vertex.
The graPHIGS API combines these vectors with the data morphing
scale factors
(**GPDMF**)
and
(**GPBDMF**)
and the vertex data mapping values to create new data mapping data
values for the rendered primitive.

See The graPHIGS Programming Interface: Understanding Concepts for a more complete explanation of how the graPHIGS API uses the various optional data values.

**Note: **

Use of any optional data other than the convexity flag, vertex colors, and boundary flags may cause unpredictable results (including locking the display) on this graphics processor. If only the High Performance 3D Color Graphics Processor is used, you should include only the supported optional data values. If your application must support multiple graphics processors INCLUDING this particular processor, the Inquire Workstation Description (This note applies ONLY to applications which will be run on the High Performance 3D Color Graphics Processor (8 or 24 bit).GPQWDT) subroutine must be used to determine the functions that each workstation supports. See also the workstation description in The graPHIGS Programming Interface: Technical Reference for the High Performance 3D Color Graphics Processor.

The normal of a Polygon 2 With Data is (0,0,1)
All points specified are placed in the
*x-y* plane (`z=0`
).
Polygon attributes are applied to this primitive.

**GPPGD2** is identified as GDP 1017.

**Note: **

Not all GDPs are supported on all workstations. Use the Inquire List of Generalized Drawing Primitives (GPQGD) subroutine to determine the GDPs supported by an opened workstation. See also the workstation description in The graPHIGS Programming Interface: Technical Reference

**Parameters**

Number of contours in the polygon definition. This field is required.

This data indicates that the application determined the
convexity of the polygon
(`0=CONCAVE, 1=CONVEX`
)
This field is optional.

The number of vertex morphing vectors specified at each vertex. The number of fullwords of vertex morphing vector data added to the other fullwords of vertex data specified per vertex cannot exceed 255 fullwords. This field is optional.

The number of data mapping values specified at each vertex. The number of data mapping values added to the other fullwords of vertex data specified per vertex cannot exceed 255 fullwords. This field is optional.

The number of data morphing vectors specified at each vertex. The number of fullwords of data morphing vector data added to the other fullwords of vertex data specified per vertex cannot exceed 255 fullwords. This field is optional.

Number of vertices in each subarea. If the number is less than three, the result is workstation dependent. This field is required for each subarea.

*x* and
*y* coordinates of a vertex.
This field is required.

The three components of a color in the current color model as contained in the graPHIGS API state list. This field is optional.

Specifies whether the corresponding boundary is to be
treated as an edge of the polygon
(`1=NOT_AN_EDGE, 2=IS_AN_EDGE`
)
These flags allow control over which parts of the
polygon's boundary are to be treated as edges.
The edge attributes are only applied to boundary segments
that have a boundary flag set to a value
of `2=IS_AN_EDGE`

Each entry of this array specifies whether the graPHIGS API draws the boundary from the corresponding vertex to the following vertex. The last entry for each subarea corresponds to the boundary from the last vertex to the first. This field is optional.

The transparency coefficient value used when performing transparency processing. A value of 0.0 is fully opaque; a value of 1.0 is fully transparent. This field is optional.

The vertex morphing vectors
dx_{1}
, dy_{1}
, dx_{2}
, dy_{2}
, ...,
dx_{n}
, dy_{n}
.
The number, *n*, of vectors in this array is
specified in the *pdata* parameter as the
vertex morphing vector count.
The array must be the same length for every vertex.
This field is optional.

The data mapping data values
x_{1}
, x_{2}
, x_{3}
, ..., x_{n}
The number, *n*, of values in this array is
specified in the *pdata* parameter as the data
mapping data count.
The array must be the same length for every vertex.
This field is optional.

The data morphing vectors
d_{11}
>, d_{12}
>, d_{13}
>, ..., d_{1n}
>,
d_{21}
>, d_{22}
>, d_{23}
>, ..., d_{2n}
>, ...,
d_{m1}
, d_{m2}
, d_{m3}
, ..., d_{mn}
The number, *n*, is
specified in the *pdata* parameter as the
data mapping data count, and the number,
*m* is
specified in the *pdata* parameter as the
data morphing vector count.
The array must be the same length for every vertex.
This field is optional.

**Error Codes**

**5**- FUNCTION REQUIRES STATE STOP OR NROP (NOT STCL)
**96**- COLOR PARAMETER OUT OF RANGE FOR CURRENT COLOR MODEL
**115**- TRANSPARENT COEFFICIENT IS INVALID
**198**- NUMBER OF SUBAREAS < ZERO
**199**- POLYGON SUBAREA HAS < ZERO POINTS
**351**- OPTIONAL DATA AVAILABILITY FLAG IS INVALID
**352**- BOUNDARY FLAG IS INVALID
**509**- DATA LENGTH VALUE < ZERO OR REQUIRED LENGTH
**557**- WIDTH PARAMETER < MINIMUM ALLOWED
**636**- FULLWORDS OF VERTEX DATA EXCEEDS MAXIMUM OF 255

**Related Subroutines**

**GPBDMF**- Set Back Data Morphing Factors
**GPBDMI**- Set Back Data Mapping Index
**GPBICD**- Set Back Interior Color Direct
**GPBICI**- Set Back Interior Color Index
**GPBISM**- Set Back Interior Shading Method
**GPBSCD**- Set Back Specular Color Direct
**GPBSCI**- Set Back Specular Color Index
**GPBSPR**- Set Back Surface Properties
**GPBTCO**- Set Back Transparency Coefficient
**GPDMF**- Set Data Morphing Factors
**GPDMI**- Set Data Mapping Index
**GPECD**- Set Edge Color Direct
**GPECI**- Set Edge Color Index
**GPEI**- Set Edge Index
**GPELT**- Set Edge Linetype
**GPESC**- Set Edge Scale Factor
**GPFDMO**- Set Face Distinguish Mode
**GPICD**- Set Interior Color Direct
**GPICI**- Set Interior Color Index
**GPII**- Set Interior Index
**GPIS**- Set Interior Style
**GPISI**- Set Interior Style Index
**GPISM**- Set Interior Shading Method
**GPPGC**- Set Polygon Culling
**GPSCD**- Set Specular Color Direct
**GPSCI**- Set Specular Color Index
**GPSPR**- Set Surface Properties
**GPTCO**- Set Transparency Coefficient
**GPVMF**- Set Vertex Morphing Factors

**RCP code**

201342210 (X'0C003D02')