MFarooqui <[EMAIL PROTECTED]> wrote:
> I would like to be able to click a number of points on the stage and have
> the area calculated .
Hi Mushtaq,
You could divide the area up into triangles, then calculate the area of each
triangle.
on getArea(point1, point2, point3)
hMin = min(point1.locH, point2.locH, point3.locH)
hMax = max(point1.locH, point2.locH, point3.locH)
vMin = min(point1.locV, point2.locV, point3.locV)
vMax = max(point1.locV, point2.locV, point3.locV)
return (hMax - hMin) * (vMax - vMin) / 2
end getArea
The difficulty will be to create a list of triangles which all fit together
to fill the area. If the shape is convex, you can create n-2 triangles
using the points 1, m-1 and m, where m varies from 3 to n. Here's the
beginning of an answer. The order in which the points are defined is
critical, so you will need to do some serious tweaking in order to get
consistent and accurate results:
on getConvexArea(aListOfPoints)
-- WARNING: INCOMPLETE FIRST DRAFT - RESULTS ARE LIKELY TO BE INACCURATE
i = aListOfPoints.count - 2
if i < 1 then
return 0
end if
point1 = aListOfPoints.getLast()
point2 = aListOfPoints[i + 1]
tArea = 0
repeat while i
point3 = aListOfPoints[i]
tArea = tArea + getArea(point1, point2, point3)
point2 = point3
i = i - 1
end repeat
return tArea
end getConvexArea
-- Example in the Message window:
Cheers,
James
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