Microsoft Small Basic

Program Listing: KRM874

List Program

'Small Basic challenge of the month February 2019 (Partial Solution)
'Write a program that will join up some random points to draw an irregular convex polygon (no side lines cross each other).

'CONFIG
dotSize = 10 'The size of the dots
maxDots = 10 'The maximum number of dots that can be generated

'INIT GRAPHICS WINDOW
gw = Desktop.Width * 0.9
gh = Desktop.Height * 0.8
GraphicsWindow.Width = gw
GraphicsWindow.Height = gh
GraphicsWindow.CanResize = "False"
GraphicsWindow.Left = (Desktop.Width - gw) / 2
GraphicsWindow.Top = (Desktop.Height - gh) / 3
GraphicsWindow.Title = "Random irregular convex polygon"
GraphicsWindow.BackgroundColor = "SkyBlue"

'MAIN
dotCount = Math.GetRandomNumber(maxDots-3) + 3 'Determine the number of dots to be generated

GraphicsWindow.PenWidth = 0
GraphicsWindow.BrushColor = "Red"
For i = 1 To dotCount 'Randomise the dots and draw them to the graphics window
x[i] = Math.GetRandomNumber(gw - dotSize)
y[i] = Math.GetRandomNumber(gh - dotSize)
connected[i] = "False"
GraphicsWindow.FillEllipse(x[i] - dotSize/2, y[i] - dotSize/2, dotSize, dotSize)
EndFor

GraphicsWindow.PenWidth = 1
GraphicsWindow.PenColor = "Black"
For i = 1 To dotCount 'Draw lines between the dots
otherDot = Math.GetRandomNumber(dotCount) 'Select a dot to draw a line to
'BUG: the following loop runs infinitely in some situations
While connected[otherDot] = "True" Or otherDot = i Or originator[otherDot] = i 'Select a different dot if this dot already has a line to it.
otherDot = Math.GetRandomNumber(dotCount)
EndWhile
GraphicsWindow.DrawLine(x[i],y[i],x[otherDot],y[otherDot])
connected[otherDot] = "True"
originator[i] = otherDot
EndFor