gSetCurveAttribs

Syntax

[C/C++:]
void gSetCurveAttribs2D(float dxbeg, float dybeg, float dxfin, float dyfin, float xbeg, float ybeg, float xfin, float yfin);
void gSetCurveAttribs3D(float dxbeg, float dybeg, float dzbeg, float dxfin, float dyfin, float dzfin, float xbeg, float ybeg, float zbeg, float xfin, float yfin, float zfin);

[F90:]
subroutine gSetCurveAttribs2D(dxbeg, dybeg, dxfin, dyfin, xbeg, ybeg, xfin, yfin)
subroutine gSetCurveAttribs3D(dxbeg, dybeg, dzbeg, dxfin, dyfin, dzfin, xbeg, ybeg, zbeg, xfin, yfin, zfin)

real, intent(in) :: dxbeg,dybeg,dzbeg,dxfin,dyfin,dzfin
real, intent(in) :: xbeg,ybeg,zbeg,xfin,yfin,zfin

Arguments

dxbeg,dybeg,dzbeg
Slope angle/derivative for start of the curve

dxfin,dyfin,dzfin
Slope angle/derivative for end of the curve

xbeg,ybeg,zbeg
Extra point defining start angle of curve

xfin,yfin,zfin
Extra point defining end angle of curve

Description

The routines gSetCurveAttribs2D() and gSetCurveAttribs3D() specify the curve end conditions which may be used in calls to the GINO 2D and 3D curve drawing routines respectively. The curve end conditions define the direction of a curve at each end.

For the 2D piecewise cubic curves, the slopes are measured in terms of the cosine and sine of the angles at each end, whereas for the 2D and 3D spline curves, the slope is measured in terms of actual gradient and therefore will need to be scaled. For monotonic spline curves, it is sufficient to set dxbeg, dxfin = 1.0 and dybeg, dyfin = y'(x) and the routine will compute the correct values.

Alternatively, the direction may be defined by an extra point through which the curve would pass if that point was included with those that actually specify the curve.

In the absence of a call to gSetCurveAttribs2D() or gSetCurveAttribs3D(), the start and end slopes default to zero, i.e 1.0 and 0.0 for the cosine and sine of the angle, and the extra points (xbeg,ybeg,zbeg) and (xfin,yfin,zfin) both default to (0.0,0.0,0.0).

gSetCurveAttribs

Syntax

Arguments

Description

See Also