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Ray-casting algorithm: Difference between revisions

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Ray-casting algorithm (view source)

Revision as of 17:51, 7 October 2016

182 bytes added ,  7 years ago
m
→‎{{header|FreeBASIC}}: indentation
(Kotlin: some improvements)
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=={{header|FreeBASIC}}==
Inpolygon by Winding number method
<lang FreeBASIC> Type Point
As Single x,y
End Type
 
 
Function inpolygon(p1() As Point,p2 As Point) As Integer
#macroMacro isleft2(L,p)
-Sgn( (L(1).x-L(2).x)*(p.y-L(2).y) - (p.x-L(2).x)*(L(1).y-L(2).y))
#endmacroEndMacro
Dim As Integer index,nextindex
Dim k As Integer=UboundUBound(p1)+1
Dim send (1 To 2) As Point
Dim wn As Integer=0
For n As Integer=1 To UboundUBound(p1)
index=n Mod k:nextindex=(n+1) Mod k
If nextindex=0 Then nextindex=1
send(1).x=p1(index).x:send(2).x=p1(nextindex).x
send(1).y=p1(index).y:send(2).y=p1(nextindex).y
If p1(index).y<=p2.y Then
If p1(nextindex).y>p2.y Then
If isleft2(send,p2)>=0 Then '=
wn=wn+1
End If
End If
Else
If p1(nextindex).y<=p2.y Then
If isleft2(send,p2)<=0 Then'=
wn=wn-1
End If
End If
End If
Next n End If
ReturnEnd wnIf
Next n
Return wn
End Function
 
Line 1,122 ⟶ 1,121:
 
Dim As Point exagon(1 To 6) ={(3,0),(7,0),(10,5),(7,10),(3,10),(0,5)}
 
'printouts
For z As Integer=1 To 4
Select Case z
Case 1: Print "squared"
Print "(5,5) " ;Tab(12);
If inpolygon(square(),Type<Point>(5,5)) Then Print "in" Else Print "out"
Print "(5,8) " ;Tab(12);
If inpolygon(square(),Type<Point>(5,8)) Then Print "in" Else Print "out"
Print "(-10,5) " ;Tab(12);
If inpolygon(square(),Type<Point>(-10,5)) Then Print "in" Else Print "out"
Print "(0,5) " ;Tab(12);
If inpolygon(square(),Type<Point>(0,5)) Then Print "in" Else Print "out"
Print "(10,5) " ;Tab(12);
If inpolygon(square(),Type<Point>(10,5)) Then Print "in" Else Print "out"
Print "(8,5) " ;Tab(12);
If inpolygon(square(),Type<Point>(8,5)) Then Print "in" Else Print "out"
Print "(10,10) " ;Tab(12);
If inpolygon(square(),Type<Point>(10,10)) Then Print "in" Else Print "out"
Print
Case 2:Print "squared hole"
Print "(5,5) " ;Tab(12);
If Not inpolygon(hole(),Type<Point>(5,5)) And inpolygon(square(),Type<Point>(5,5)) Then Print "in" Else Print "out"
Print "(5,8) " ;Tab(12);
If Not inpolygon(hole(),Type<Point>(5,8)) And inpolygon(square(),Type<Point>(5,8))Then Print "in" Else Print "out"
Print "(-10,5) " ;Tab(12);
If Not inpolygon(hole(),Type<Point>(-10,5))And inpolygon(square(),Type<Point>(-10,5)) Then Print "in" Else Print "out"
Print "(0,5) " ;Tab(12);
If Not inpolygon(hole(),Type<Point>(0,5))And inpolygon(square(),Type<Point>(0,5)) Then Print "in" Else Print "out"
Print "(10,5) " ;Tab(12);
If Not inpolygon(hole(),Type<Point>(10,5))And inpolygon(square(),Type<Point>(10,5)) Then Print "in" Else Print "out"
Print "(8,5) " ;Tab(12);
If Not inpolygon(hole(),Type<Point>(8,5))And inpolygon(square(),Type<Point>(8,5)) Then Print "in" Else Print "out"
Print "(10,10) " ;Tab(12);
If Not inpolygon(hole(),Type<Point>(10,10))And inpolygon(square(),Type<Point>(10,10)) Then Print "in" Else Print "out"
Print
Case 3:Print "strange"
Print "(5,5) " ;Tab(12);
If inpolygon(strange(),Type<Point>(5,5)) Then Print "in" Else Print "out"
Print "(5,8) " ;Tab(12);
If inpolygon(strange(),Type<Point>(5,8)) Then Print "in" Else Print "out"
Print "(-10,5) " ;Tab(12);
If inpolygon(strange(),Type<Point>(-10,5)) Then Print "in" Else Print "out"
Print "(0,5) " ;Tab(12);
If inpolygon(strange(),Type<Point>(0,5)) Then Print "in" Else Print "out"
Print "(10,5) " ;Tab(12);
If inpolygon(strange(),Type<Point>(10,5)) Then Print "in" Else Print "out"
Print "(8,5) " ;Tab(12);
If inpolygon(strange(),Type<Point>(8,5)) Then Print "in" Else Print "out"
Print "(10,10) " ;Tab(12);
If inpolygon(strange(),Type<Point>(10,10)) Then Print "in" Else Print "out"
Print
Case 4:Print "exagon"
Print "(5,5) " ;Tab(12);
If inpolygon(exagon(),Type<Point>(5,5)) Then Print "in" Else Print "out"
Print "(5,8) " ;Tab(12);
If inpolygon(exagon(),Type<Point>(5,8)) Then Print "in" Else Print "out"
Print "(-10,5) " ;Tab(12);
If inpolygon(exagon(),Type<Point>(-10,5)) Then Print "in" Else Print "out"
Print "(0,5) " ;Tab(12);
If inpolygon(exagon(),Type<Point>(0,5)) Then Print "in" Else Print "out"
Print "(10,5) " ;Tab(12);
If inpolygon(exagon(),Type<Point>(10,5)) Then Print "in" Else Print "out"
Print "(8,5) " ;Tab(12);
If inpolygon(exagon(),Type<Point>(8,5)) Then Print "in" Else Print "out"
Print "(10,10) " ;Tab(12);
If inpolygon(exagon(),Type<Point>(10,10)) Then Print "in" Else Print "out"
Print
End Select
Next z
Sleep</lang>▼
sleep
▲</lang>
Output:
<pre>squared
squared
(5,5) in
(5,8) in
Line 1,229 ⟶ 1,227:
(10,5) in
(8,5) in
(10,10) out</pre>
</pre>
 
=={{header|Go}}==
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