graPHIGS Programming Interface: Subroutine Reference

The graPHIGS Programming Interface : Subroutine Reference

GPQLSR - Inquire Light Source Representation

GPQLSR (wsid, index, type, errind, lstype, color, data)

Note:

This subroutine is a Workstation State List (WSL) inquiry. For an overview, see "WSL Inquiries"

Purpose

Use GPQLSR to inquire the current attribute values in the specified entry in the light source table of the specified workstation.

If the inquired information is available, then the graPHIGS API sets the error indicator to zero and returns the values in the output parameters. If the inquired information is unavailable, then the error indicator (errind) contains an error number indicating the reason, and the values returned in the output parameters are unpredictable.

The data parameter (data) must be large enough to include the maximum number of light source parameters.

Parameters

wsid -- specified by user, fullword integer

Workstation identifier.

index -- specified by user, fullword integer

Light source table index (>=1)

type -- specified by user, fullword integer

Type of returned values (1=SET )

errind -- returned by the graPHIGS API, fullword integer

Error indicator. If the error indicator is zero, the request has been completed. Otherwise, one of the following errors exists:

25: SPECIFIED WORKSTATION DOES NOT EXIST
35: WORKSTATION HAS ONLY INPUT CAPABILITIES
254: LIGHT SOURCE INDEX < ONE
255: LIGHT SOURCE INDEX EXCEEDS THE WORKSTATION TABLE CAPACITY
534: TYPE VALUE IS INVALID

lstype -- returned by the graPHIGS API, fullword integer

Light source type (1=AMBIENT, 2=DIRECTIONAL, 3=POSITIONAL, 4=SPOT )

color -- returned by the graPHIGS API, four fullwords of data

Light source color. This parameter includes one of the following two formats:

   indexed format                       direct format
    -------------                       -------------
  0 |          1| fullword integer    0 |          2| fullword integer
    |-----------|                       |-----------|
  4 |color index| fullword integer    4 |component 1| short floating-point number
    |-----------|                       |-----------|
  8 |   reserved| fullword integer    8 |component 2| short floating-point number
    |-----------|                       |-----------|
 12 |   reserved| fullword integer   12 |component 3| short floating-point number
    -------------                       -------------

data -- returned by the graPHIGS API, array of short floating-point numbers

List of light source parameters. Values returned to this parameter depend on the light source type. The application must supply storage for this parameter that is large enough to contain the maximum data listed below:

1=AMBIENT

None

2=DIRECTIONAL

Light source direction - 3 short floating-point numbers (WC)

3=POSITIONAL

Light source position - 3 short floating-point numbers (WC)

Attenuation coefficients - 2 short floating-point numbers

4=SPOT

Light source position - 3 short floating-point numbers (WC) Light source direction - 3 short floating-point numbers (WC) Concentration exponent - short floating-point number Attenuation coefficients - 2 short floating-point numbers Spread angle - short floating-point number

Error Codes

None

Related Subroutines

GPLSR: Set Light Source Representation

RCP code

201339150 (X'0C00310E')