ARC primitive example

Hello all,

here you find the code to draw arc primitives using NSBezierPath.

from AppKit import NSBezierPath
# I got the NSBezierPath thing from: 
# http://developer.apple.com/documentation/Cocoa/Conceptual/CocoaDrawingGuide/Paths/chapter_6_section_5.html#//apple_ref/doc/uid/TP40003290-CH206-BBCBGFBH
 
 
size(450, 400)
background(0.5,0.5,0.53)
font("Monaco", 9)
 
x0,y0   = 330,230     # starting point
x1,y1   = 140, 260    # corner point
x2,y2   = 140, 130     
radius1 = 60        # arc radius
x3,y3   = 140, 30    
x4,y4   = 110, 130
radius2 = 7   
x5,y5   = 80, 230 
x6,y6   = 45, 130 
radius3 = 20
radius_cw = 0       # clockwise arc radius
radius_ccw = 0      # counterclockwise arc radius
 
 
def arc(self, x1, y1, x2, y2, radius):
        self._segment_cache = None
        self.inheritFromContext()
        self._nsBezierPath.appendBezierPathWithArcFromPoint_toPoint_radius_( (x1, y1), (x2, y2), radius)
        
 
def arc_c(self, originx, originy, radius, startangle, endangle, clockwise=True):
        self._segment_cache = None
        self.inheritFromContext() 
        if clockwise: # the clockwise direction is relative to the orientation of the axis, so it looks flipped compared to the normal Cartesial Plane
            self._nsBezierPath.appendBezierPathWithArcWithCenter_radius_startAngle_endAngle_clockwise_( (originx, originy), radius, startangle, endangle, 1)
        else:
            self._nsBezierPath.appendBezierPathWithArcWithCenter_radius_startAngle_endAngle_( (originx, originy), radius, startangle, endangle)
 
                
# DRAW THE LINE WITH the function "arc": appendBezierPathWithArcFromPoint_toPoint_radius_()
strokewidth(2)
stroke(1, 0.8, 0)
nofill()
b = BezierPath()
b.moveto(x0, y0)
arc(b, x1, y1 , x2, y2, radius1)
b.lineto(x2,y2)
arc(b, x3, y3, x4, y4, radius2)
b.lineto(x4, y4)
arc(b, x5, y5, x6, y6, radius3)
b.lineto(x6, y6)
#print b.path
b.draw() 
 
 
# DRAW the clockwise arcs with the function "arc_c": appendBezierPathWithArcWithCenter_radius_startAngle_endAngle_clockwise_()
strokewidth(2.0)
stroke(0.8, 0.8, 0.8)
nofill()
cw = BezierPath()
for i in range(10):
    radius_cw = (i*6) + 4
    cw.moveto(x0 + radius_cw, y0)
    arc_c( cw, x0, y0, radius_cw, 0, 360-(i*72), 1 )  
cw.draw()
 
 
# DRAW the counterclockwise arcs with the function "arc_c": appendBezierPathWithArcWithCenter_radius_startAngle_endAngle_()
strokewidth(2.0)
stroke(0.8, 0.8, 0.8)
nofill()
ccw = BezierPath()
for i in range(6):
    radius_ccw = (i*6) + 10
    ccw.moveto(x6 + radius_ccw,y6)
    arc_c( ccw, x6, y6, radius_ccw, 0, 360-(i*50), 0 )    
ccw.draw()
 
 
 
 
#################################################################
 
def linedash(path, segment=10, gap=4): 
    # this is just to visualize the points
    path._nsBezierPath.setLineDash_count_phase_([segment, gap], 2, 50)
    return path
    
def oval_c(x, y, d):
    # draws origin-centered circles
    r = d/2.0
    oval(x-r, y-r, d, d)
    
def pointlabel(x, y, t):
    oval_c(x, y, 5)
    text(t ,x ,y+14)
 
# DRAW DOTTED LINE
strokewidth(0.4)
stroke(0.9)
nofill()
v = BezierPath()
v.moveto(x0, y0)
v.lineto(x1, y1)
v.lineto(x2, y2)
v.lineto(x3, y3)
v.lineto(x4, y4)
v.lineto(x5, y5)
v.lineto(x6, y6)
linedash(v, segment=4)
drawpath(v)
 
 
# DRAW THE POINTS/LABELS
fill(0.5,0,0)
nostroke()
pointlabel(x0, y0, "P0")
pointlabel(x1, y1, "P1")
pointlabel(x2, y2, "P2")
pointlabel(x3, y3, "P3")
pointlabel(x4, y4, "P4")
pointlabel(x5, y5, "P5")
pointlabel(x6, y6, "P6")