File to Edit to add backplot tabs

Subfiles:
gosper.ngc Recursive-calls example (adapted from flowsnake.ngc)
The inputs for gosper specify the two end points
of a line that are one side of an equilateral triangle
* helix.ngc Helix (inside/outside, cw/ccw) Also does D Shape.
* helix_rtheta.ngc Invoke helix.ngc with center specified as r,theta
* hole_circle.ngc Invoke helix.ngc for holes milled on a circular pattern
*+ slot.ngc Slot (inside, ccw) (adapted from useful-subroutines.ngc)
*+ iquad.ngc inside quadrilateral (cw/ccw)
*+ oquad.ngc outside quadrilateral (cw/ccw)
*+ ihex.ngc inside regular hexagon (cw/ccw)
*+ ohex.ngc outside regular hexagon (cw/ccw)
hw.ngc Text from truetype-tracer
Generated with the following shell commands:
cat <<eof >|hw.ngc
o<hw> sub
#<zsafe> = #1
#<zcut> = #2
#<scale> = #3 (=0.0003)
#<feed> = #4
eof
truetype-tracer HelloWorld | grep -Eiv =\|m2\|m02 >>hw.ngc
echo "o<hw> endsub" >>hw.ngc

xyz.ngc Axis exerciser-- test program for running x,y,z axes
in simple patterns useful for servo tuning etc.
backlash.ngc Use for backlash measurements with indicator on x,y,or z axis

Postamble Files:
bye.ngc Simple example postamble with user message

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Helper files (these contain utility routines used by the Subfiles above):
gosper_sub.ngc Recursive function used with gosper.ngc
dir.ngc Determine direction for polygon traversal
entry.ngc Compute a quarter-arc preentry and radius vector
cross.ngc Cross product for two vectors
dot.ngc Dot product and cosine for two vectors
line.ngc Compute length, angle, cos, and sin for a line
move.ngc Compute coordinants for rotation, scale, and offset
ostop.ngc Insert optional stop with continue message
spin.ngc Startup message for user to set spindle speed
M110 Clear notifications in axis-gui