ZeroSegs(D3nfb)

ZeroSegs, SolidZeroSeg -- draw Bresenham lines

Synopsis

#include "nfbGCStr.h"

void xxxFillZeroSegs (
	GCPtr pGC,
	DrawablePtr pDrawable,
	BresLinePtr plines,
	int nlines);


void xxxSolidZeroSeg (
        GCPtr pGC,
        DrawablePtr pDraw,
        int signdx,
        int signdy,
        int axis,
        int x1,
        int y1,
        int e,
        int e1,
        int e2,
        int len)

void
genSolidZeroSegs(
	GCPtr pGC,
	DrawablePtr pDrawable,
	BresLinePtr plines,
	int nlines)

xxx is the routine's prefix. Valid values are gen to use the default routines or your driver's prefix if you are rewriting these routines to use the specific capabilities of your hardware. xxx is the routine's prefix. Valid values are gen to use the default routine or your driver's prefix if you are rewriting this routine to use the specific capabilities of your hardware.

Description

These routines are used to draw multiple Bresenham lines.

FillZeroSegs( ) depends upon the driver setting NFB_POLYBRES in the nfbSetOptions(D3nfb) call.

SolidZeroSeg( ) is used if NFB_POLYBRES is not defined. In this case, NFB will pass each Bresenham line command to the driver as it is calculated. This may benefit slower graphics engines in that the current line can be drawn by the adapter while the next line is calculated by NFB.

Arguments

pGC: pointer to GC information
pDrawable: pointer to Drawable information
plines: list of Bresenham line parameters
nlines: number of lines in plines
x1, y1: line starting points
signdx, signdy: direction flags
axis: major axis
len: length of line
e, e1, e2: decision variables

Exit codes

None.

Usage notes

These routines are optional.

Version applicability

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

References

nfbGCOps(D4nfb)

``Bresenham objects'' in Developing NFB graphics adapter drivers