Draw spokes on a wheel

[Dick Kriesel]

On 3/17/06 10:26 AM, "Mark Talluto" <userev at canelasoftware.com> wrote:

> I need a little help drawing spokes to a wheel.  This is actually
> used in a vision test.  I have an image here to help illustrate the
> madness.  I am sure someone like Jim Ault is shaking his head right
> now.  <http://www.canelasoftware.com/pub/rev/astig.jpg>
> 
> I have been using an image, but would like to offer the ability to
> adjust the line length and thickness.  The new antialiasing feature
> will also be handy.  Thanks for any input.

Here's another way to draw the spokes:

on drawAstig pInnerDiameter,pOuterDiameter,pLineSize
  repeat with i = 0 to 345 step 15
    create graphic
    set the style of it to "oval"
    set the height of it to pOuterDiameter
    set the width of it to pOuterDiameter
    set the angle of it to i
    set the arcangle of it to 15
    set the opaque of it to "true"
    set the lineSize of it to pLineSize
  end repeat
  create graphic
  set the style of it to "oval"
  set the height of it to pInnerDiameter
  set the width of it to pInnerDiameter
  set the opaque of it to "true"
  set the foregroundColor of it to "white"
  create graphic
  set the style of it to "oval"
  set the height of it to pOuterDiameter+5
  set the width of it to pOuterDiameter+5
  set the foregroundColor of it to "white"
  set the lineSize of it to pLineSize + 4
end drawAstig

Applying the hour numbers seems to require a different approach.  If you use
turtle graphics, you can probably both draw the spokes and accurately
position label fields containing the hour numbers.

-- Dick