How do I draw a radar triangle?

Or you can draw the pie like I did in the "How to draw something like a pie chart" post.

Here is some example code that you can change to draw your radar thing:

SuperStrict

Graphics 800, 600, 0

Local pie1:TPieClock = TPieClock.Create(300, 300, 12, 2, 20000)'	centerX, centerY, radius, margin, duration
pie1.start()
Local pie2:TPieClock = TPieClock.Create(500, 300, 124, 10, 10000)'	centerX, centerY, radius, margin, duration
pie2.start()

While Not KeyHit(KEY_ESCAPE)
	Cls
	pie1.update()
	pie2.update()

	pie1.draw()
	pie2.draw()
	Flip
Wend
End

Type TPieClock
	Field pfX#
	Field pfY#
	Field pfR#
	Field pfMargin#
	Field pfAngle# = 0
	Field pfCircumference#	'I use this to calculate the correct number of lines to be drawn in the drawSegment() method

	'	background color
	Field piR1% = 70
	Field piG1% = 90
	Field piB1% = 90

	'	segment color
	Field piR2% =  30
	Field piG2% = 170
	Field piB2% =  80

	'	timer values
	Field piStart%
	Field pfDuration#		'in milliseconds
	
	Function Create:TPieClock(fx#, fy#, fr#, fm# = 0, fDur# = 1000)
		Local p:TPieClock = New TPieClock
		p.pfX = fx
		p.pfY = fy
		p.pfR = fr
		p.pfMargin = Min(fm, fr-1)
		p.pfCircumference = 2 * Pi * (fr-fm)
		p.pfDuration = fDur
		Return p
	End Function

	Method start()
		piStart = MilliSecs()
	End Method

	Method update()
		Local p# = eTime()
		If p>=1 Then 
			'ok, time's up
			p = 1
		End If
		pfAngle = p * 360
	End Method
	
	Method draw()
		SetColor(piR1, piG1, piB1)
		DrawOval(pfX - pfR, pfY - pfR, pfR * 2, pfR * 2)
		drawSegment() 
	End Method
	
	'	draws the segment
	Method drawSegment()
		SetColor(piR2, piG2, piB2)
		Local r# = pfR - pfMargin
		Local s# = pfAngle / ((pfAngle/360) * pfCircumference)
		'		s# = angle Step size; To be sure the While-Wend loop will draw exactly enough lines To cover the segment 
		
		Local a# = 0
		While a < pfAngle
			DrawLine(pfX-0.5, pfY-0.5, pfX-0.5 + Cos(a-90) * r, pfY-0.5 + Sin(a-90) * r, 0)
			a:+s
		Wend
		DrawLine(pfX-0.5, pfY-0.5, pfX-0.5 + Cos(pfAngle-90) * r, pfY-0.5 + Sin(pfAngle-90) * r, 0)
		'		I draw this line at the exact angle location 
	End Method

	Method eTime#()
		Return (MilliSecs() - piStart) / pfDuration
	End Method
	
End Type

Good luck!