- Bezier Curve drawing functions
- Bezier Curve limit : 32 points max
- C# original porject: http://www.codeproject.com/Articles/252 ... ade-Simple
Code: Select all
DeclareModule BezierCurve
#Default_CurvePoints=1000 ; Default curve drawing precision (higher = better)
#Default_FrontColor=$FFFFFFFF + 1 ; Determines if curve will be drawn with current Purebasic FrontColor
#Default_BezierPointColor=$FFFFFF ; Default bezier point color (if visible)
Structure DOUBLE_POINT
x.d
y.d
EndStructure
Declare CalculateBezier2D(Array bezierPoints.DOUBLE_POINT(1), Array curvePoints.DOUBLE_POINT(1))
Declare BezierCurveN(Array NPoints.DOUBLE_POINT(1), color=#Default_FrontColor, curvePoints=#Default_CurvePoints, bezierPointVisible=#False, bezierPointColor=#Default_BezierPointColor)
Declare BezierCurve3(x1.d, y1.d, x2.d, y2.d, x3.d, y3.d, color=#Default_FrontColor, curvePoints=#Default_CurvePoints, bezierPointVisible=#False, bezierPointColor=#Default_BezierPointColor)
Declare BezierCurve4(x1.d, y1.d, x2.d, y2.d, x3.d, y3.d, x4.d, y4.d, color=#Default_FrontColor, curvePoints=#Default_CurvePoints, bezierPointVisible=#False, bezierPointColor=#Default_BezierPointColor)
Declare BezierCurveParse(parsedPoints.s="1,1,2,2", color=#Default_FrontColor, curvePoints=#Default_CurvePoints, bezierPointVisible=#False, bezierPointColor=#Default_BezierPointColor)
EndDeclareModule
Module BezierCurve
EnableExplicit
Global Dim FactorialLookup.d(32)
FactorialLookup(0)=1.0
FactorialLookup(1)=1.0
FactorialLookup(2)=2.0
FactorialLookup(3)=6.0
FactorialLookup(4)=24.0
FactorialLookup(5)=120.0
FactorialLookup(6)=720.0
FactorialLookup(7)=5040.0
FactorialLookup(8)=40320.0
FactorialLookup(9)=362880.0
FactorialLookup(10)=3628800.0
FactorialLookup(11)=39916800.0
FactorialLookup(12)=479001600.0
FactorialLookup(13)=6227020800.0
FactorialLookup(14)=87178291200.0
FactorialLookup(15)=1307674368000.0
FactorialLookup(16)=20922789888000.0
FactorialLookup(17)=355687428096000.0
FactorialLookup(18)=6402373705728000.0
FactorialLookup(19)=121645100408832000.0
FactorialLookup(20)=2432902008176640000.0
FactorialLookup(21)=ValD("51090942171709440000.0")
FactorialLookup(22)=ValD("1124000727777607680000.0")
FactorialLookup(23)=ValD("25852016738884976640000.0")
FactorialLookup(24)=ValD("620448401733239439360000.0")
FactorialLookup(25)=ValD("15511210043330985984000000.0")
FactorialLookup(26)=ValD("403291461126605635584000000.0")
FactorialLookup(27)=ValD("10888869450418352160768000000.0")
FactorialLookup(28)=ValD("304888344611713860501504000000.0")
FactorialLookup(29)=ValD("8841761993739701954543616000000.0")
FactorialLookup(30)=ValD("265252859812191058636308480000000.0")
FactorialLookup(31)=ValD("8222838654177922817725562880000000.0")
FactorialLookup(32)=ValD("263130836933693530167218012160000000.0")
Procedure.d Ni(n, i)
Protected ni.d
Protected a1.d=FactorialLookup(n)
Protected a2.d=FactorialLookup(i)
Protected a3.d=FactorialLookup(n - i)
ni=a1 / (a2 * a3)
ProcedureReturn ni
EndProcedure
;Calculate Bernstein basis
Procedure.d Bernstein(n, i, t.d)
Protected basis.d
Protected ti.d ; t^i
Protected tni.d ; (1 - t)^i
;/* Prevent problems With pow */
If (t=0.0 And i=0)
ti=1.0
Else
ti=Pow(t, i)
EndIf
If (n=i And t=1.0)
tni=1.0
Else
tni=Pow((1 - t), (n - i))
EndIf
;//Bernstein basis
basis=Ni(n, i) * ti * tni;
ProcedureReturn basis
EndProcedure
Procedure CalculateBezier2D(Array b.DOUBLE_POINT(1), Array c.DOUBLE_POINT(1))
Protected npts=ArraySize(b()) + 1 ; bezier points
Protected cpts=ArraySize(c()) + 1 ; curve points
Protected icount=0, jcount
Protected t.d=0, dt.d=1.0 / (cpts - 1)
Protected i1, i
;Calculate points on curve
For i1=0 To cpts-1
If ((1.0 - t)<5e-6) : t=1.0 : EndIf
jcount=0
c(icount)\x=0.0
c(icount)\y=0.0
For i=0 To npts-1
Protected basis.d=Bernstein(npts - 1, i, t)
c(icount)\x + basis * b(jcount)\x
c(icount)\y + basis * b(jcount)\y
jcount + 1
Next
icount + 1
t + dt
Next
EndProcedure
Procedure DrawBezier2D(Array bezierPoints.DOUBLE_POINT(1), Array curvePoints.DOUBLE_POINT(1), color, bezierPointVisible, bezierPointColor)
Protected i
CalculateBezier2D(bezierPoints(), curvePoints())
If bezierPointVisible
For i=0 To ArraySize(bezierPoints())
Circle(bezierPoints(i)\x, bezierPoints(i)\y, 2, bezierPointColor)
Next
EndIf
If color=#Default_FrontColor
For i=0 To ArraySize(curvePoints())-1
LineXY(curvePoints(i)\x, curvePoints(i)\y, curvePoints(i + 1)\x, curvePoints(i + 1)\y)
Next
Else
For i=0 To ArraySize(curvePoints())-1
LineXY(curvePoints(i)\x, curvePoints(i)\y, curvePoints(i + 1)\x, curvePoints(i + 1)\y, color)
Next
EndIf
EndProcedure
Procedure BezierCurveN(Array bezierPoints.DOUBLE_POINT(1), color=#Default_FrontColor, curvePoints=#Default_CurvePoints, bezierPointVisible=#False, bezierPointColor=#Default_BezierPointColor)
Protected Dim curvePoints.DOUBLE_POINT(curvePoints)
DrawBezier2D(bezierPoints(), curvePoints(), color, bezierPointVisible, bezierPointColor)
EndProcedure
Procedure BezierCurve3(x1.d, y1.d, x2.d, y2.d, x3.d, y3.d, color=#Default_FrontColor, curvePoints=#Default_CurvePoints, bezierPointVisible=#False, bezierPointColor=#Default_BezierPointColor)
Protected Dim bezierPoints.DOUBLE_POINT(2)
bezierPoints(0)\x=x1 : bezierPoints(0)\y=y1
bezierPoints(1)\x=x2 : bezierPoints(1)\y=y2
bezierPoints(2)\x=x3 : bezierPoints(2)\y=y3
BezierCurveN(bezierPoints(), color, curvePoints, bezierPointVisible, bezierPointColor)
EndProcedure
Procedure BezierCurve4(x1.d, y1.d, x2.d, y2.d, x3.d, y3.d, x4.d, y4.d, color=#Default_FrontColor, curvePoints=#Default_CurvePoints, bezierPointVisible=#False, bezierPointColor=#Default_BezierPointColor)
Protected Dim bezierPoints.DOUBLE_POINT(3)
bezierPoints(0)\x=x1 : bezierPoints(0)\y=y1
bezierPoints(1)\x=x2 : bezierPoints(1)\y=y2
bezierPoints(2)\x=x3 : bezierPoints(2)\y=y3
bezierPoints(3)\x=x4 : bezierPoints(3)\y=y4
BezierCurveN(bezierPoints(), color, curvePoints, bezierPointVisible, bezierPointColor)
EndProcedure
Procedure BezierCurveParse(parsedPoints.s="1,1,2,2", color=#Default_FrontColor, curvePoints=#Default_CurvePoints, bezierPointVisible=#False, bezierPointColor=#Default_BezierPointColor)
Static regexSeparators
If Not regexSeparators
regexSeparators=CreateRegularExpression(#PB_Any, "[^\de +.-]")
EndIf
parsedPoints=RemoveString(ReplaceRegularExpression(regexSeparators, parsedPoints, ","), " ") ;value samples: 2.0e3,2000,-0.1,-1e-2,+11,11
Protected Dim bezierPoints.DOUBLE_POINT(CountString(parsedPoints, ",") / 2)
Protected i, npts
For i=0 To ArraySize(bezierPoints())
npts=1 + i*2
bezierPoints(i)\x=ValD(StringField(parsedPoints, npts, ",")) : bezierPoints(i)\y=ValD(StringField(parsedPoints, npts + 1, ","))
Next
BezierCurveN(bezierPoints(), color, curvePoints, bezierPointVisible, bezierPointColor)
EndProcedure
EndModule
CompilerIf #PB_Compiler_IsMainFile
UseModule BezierCurve
DisableExplicit
; ********************
; EXAMPLE
; ********************
If OpenWindow(0, 0, 0, 800, 600, "2DDrawing Bezier Drawing", #PB_Window_SystemMenu | #PB_Window_ScreenCentered)
If CreateImage(0, 800, 600, 32, RGB(0, 0, 0)) And StartDrawing(ImageOutput(0))
BezierCurve3(50, 400, 225, 400, 400, 50, RGB(200, 60, 10), #Default_CurvePoints, #True, RGB(255, 100, 0))
BezierCurve4(50, 400, 50, 300, 225, 50, 400, 50, RGB(0, 245, 255), #Default_CurvePoints, #True, RGB(0, 96, 255))
BezierCurveParse("50,400,4.0e2,400, 100,380, 350,70, 50,50,400,50", RGB(206, 0, 255), #Default_CurvePoints, #True, RGB(255, 0, 219))
StopDrawing()
ImageGadget(0, 0, 0, 200, 200, ImageID(0))
EndIf
Repeat: Until WaitWindowEvent()=#PB_Event_CloseWindow
EndIf
CompilerEndIf
