SclGraphicsInsertCircularArc

Overview

Insert a circular arc into the currently open node of the graphics database. A circular arc is a portion of the circumference of a circle.

Synopsis

SclGraphicsInsertCircularArc $x1 $y1 $z1 $x2 $y2 $z2 $x3 $y3 $z3

Description

This command inserts a circular arc which is defined by three points on its circumference. The order of the points is important. The arc starts at the first point, passes through the second point and terminates at the third point. Defining an arc in this way permits an arc of any orientation to be defined. The arc line weight, line pattern, and colour are determined by other SclGraphics commands.

Arguments

x1, y1, z1, x2, y2, z2, x3, y3, z3

Pass by value. The XYZ coordinates of three points on the circular arc. If the arc is to be parallel with the horizontal plane then use the same Z value for all 3 points. If these values place the arc outside the screen extents the arc will not be visible.

Returns

The key to the circular arc so that it can be selectively deleted using SclGraphicsDeleteByKey.

Examples

#
# Create a node and insert a circular arc
#
SclGraphicsOpen mygraphicsnode
  # insert the arc and remember its key
  set key [SclGraphicsInsertCircularArc 100 200 50 110 210 50 120 200 50 ]
  # set the rendering attributes
  SclGraphicsSetColour "lines=yellow"
  SclGraphicsSetLineWeight 2
  SclGraphicsSetLinePattern "-.-."
SclGraphicsClose
# and now make sure we can see it
SclGraphicsUpdateDisplay