ddxScreenRequest(D4nfb)

ddxScreenRequest -- graphics driver initialization information for SYS layer

Synopsis

#include "ddxScreen.h"

Description

The ddxScreenRequest structure is passed into the xxxProbe routine for every DDX layer loaded. It contains information from the SYS layer that is needed for the driver to initialize the board. This structure is initialized by the SYS module by reading the grafinfo(DSP/4dsp) file and command line arguments. Your xxxProbe routine supplies a pointer to this structure as an argument.

Structure definition

typedef struct _ddxScreenRequest {
	char *mode;
	char *type;
	unsigned char ddxLoad;
	unsigned char boardNum;
	unsigned char dfltClass;
	unsigned char dfltDepth;
	unsigned char dfltBpp;
	unsigned char dfltPad;
	unsigned char nextLeft;
	unsigned char nextRight;
	unsigned char nextAbove;
	unsigned char nextBelow;
	grafData *grafinfo;
} ddxScreenRequest;

Structure members

The members are:

*mode: grafinfo mode string being used by this adapter. The format is vendor.model.class.mode. For example, trident.impact.svga.1024x768-256.
*type: character driver name. This must consist of no fewer than three characters and no more than five and is taken from the value of the XDRIVER field in the grafinfo(DSP/4dsp) file.
ddxLoad: type of driver being used. Valid values are DDX_LOAD_STATIC or DDX_LOAD_DYNAMIC.
boardNum: number of the board you initialized. Determined by the order in which the grafinfo mode string appears in the grafdev file.
dfltClass: visual class of this adapter mode. Obtained from the grafinfo file's VISUAL field.
dfltDepth: support depth of this adapter mode. Obtained from the grafinfo file's DEPTH field.
dfltBpp: number of bits needed to represent a pixel. Calculated from DEPTH. Legal values are 1, 4, 8, 16, and 32.
dfltPad: number of bits to which pixmaps must be padded. Typical value is 32.
nextLeft: screen to the left of this one. Reserved for possible future support of multihead.
nextRight: screen to the right of this one. Reserved for possible future support of multihead.
nextAbove: screen above this one. Reserved for possible future support of multihead.
nextBelow: screen below this one. Reserved for possible future support of multihead.
*grafinfo: pointer to the grafinfo data.

Version applicability

This structure is supported for NFB drivers on all releases of SCO OpenServer 5, SVR5, and AIX 5L.

References

ddxScreenInfo(D4nfb)

``Initializing the hardware'' in Developing NFB graphics adapter drivers