CURVE_RESOLUTION(3G)

NAME

curve_resolution − set resolution for splines and arcs

SYNOPSIS

C Syntax:

void curve_resolution (fildes,coordinate_type,u_interior,v_interior,
u_exterior,v_exterior);
int fildes,coordinate_type;
float u_interior,v_interior,u_exterior,v_exterior;

FORTRAN77 Syntax:

subroutine curve_resolution (fildes,coordinate_type,u_interior,v_interior,
u_exterior,v_exterior)
integer*4 fildes,coordinate_type
real u_interior,v_interior,u_exterior,v_exterior

Pascal Syntax:

procedure curve_resolution (fildes,coordinate_type:integer;
u_interior,v_interior,u_exterior,v_exterior:real);

DESCRIPTION

Input Parameters

fildes Integer file descriptor returned by gopen when an I/O path to a graphics device is opened.

coordinate_type Identifies the scale of the resolution value:
DC_VALUES=0, METRIC=1, VDC_VALUES=2, STEP_SIZE=3

u_interior,v_interior,u_exterior,v_exterior
Maximum distance between sample points on spline_curves and spline_surfaces along interior and exterior boundaries, or the length of elliptical arc chord segments (u_exterior).

Discussion

Curve_resolution sets the sample size used between knots in splines, curves, and surfaces; or the chord length of elliptical arc segments. Coordinate types are as follows:

• DC_VALUES is set directly in pixels.

• VDC_VALUES defines a value based on the current vdc_extent.

• METRIC assumes the value is in millimeters.

• STEP_SIZE is a value used directly to increment u and v from zero to their maximum values, or to set a delta radian value for arcs.

If an interior value is specified to be less than the corresponding exterior value, the interior value is set to the exterior value. Interior values are also limited to be no more than a device-dependent factor larger than the exterior values, but such that at least 3 samples result.

DEFAULTS

Exterior values are set to 2 mm and interior values are set to 5 mm.

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