import pygame
from pygame.locals import *
import sys, os
import cPickle
if sys.platform == 'win32' or sys.platform == 'win64':
    os.environ['SDL_VIDEO_CENTERED'] = '1'
pygame.init()

Screen = (800,600)
icon = pygame.Surface((1,1)); icon.set_alpha(0); pygame.display.set_icon(icon)
pygame.display.set_caption("Kochanek-Bartels Spline - Ian Mallett - 1.0.0 - May 2008")
Surface = pygame.display.set_mode(Screen)

Resolution = 100

c = 0
t = 0
b = 0

ControlPoints = []
interpolated_points = []
save_points = False
def SaveLines():
    global interpolated_points
    pt = None
    lines = []
    for i in range(len(interpolated_points)):
        if pt != interpolated_points[i]:
            pt = interpolated_points[i]
            lines.append(pt)

    import pprint
    pp = pprint.PrettyPrinter(indent=4)
    s = "lines=" + pp.pformat(lines)
    print s
    #f = open("out.pts",'wb')
    #cPickle.dump(lines,f,2)
    #f.close()
    #print lines
        
class ControlPoint:
    def __init__(self,pos):
        self.pos = pos
pressing = False

def DrawCurve():
    global t,b,c, interpolated_points, save_points
    tans = []
    tand = []
    for x in xrange(len(ControlPoints)-2):
        tans.append([])
        tand.append([])

    cona = (1-t)*(1+b)*(1-c)*0.5
    conb = (1-t)*(1-b)*(1+c)*0.5
    conc = (1-t)*(1+b)*(1+c)*0.5
    cond = (1-t)*(1-b)*(1-c)*0.5

    i = 1
    while i < len(ControlPoints)-1:
        pa = ControlPoints[i-1]
        pb = ControlPoints[i]
        pc = ControlPoints[i+1]
                
        x1 = pb.pos[0] - pa.pos[0]
        y1 = pb.pos[1] - pa.pos[1]
        #z1 = pb.pos[2] - pa.pos[2]
        x2 = pc.pos[0] - pb.pos[0]
        y2 = pc.pos[1] - pb.pos[1]
        #z2 = pc.pos[2] - pb.pos[2]
                
        tans[i-1] = (cona*x1+conb*x2, cona*y1+conb*y2) #cona*z1+conb*z2
        tand[i-1] = (conc*x1+cond*x2, conc*y1+cond*y2) #conc*z1+cond*z2
        
        i += 1

    #render spline (Your camera part)
    t_inc = 0.05
    i = 1
    while i < len(ControlPoints)-2:
        p0 = ControlPoints[i]
        p1 = ControlPoints[i+1]
        m0 = tand[i-1]
        m1 = tans[i]
        #draw curve from p0 to p1
        Lines = [(p0.pos[0],p0.pos[1])]
        t_iter = t_inc
        while t_iter < 1.0:
            h00 = ( 2*(t_iter**3)) - ( 3*(t_iter**2)) + 1
            h10 = ( 1*(t_iter**3)) - ( 2*(t_iter**2)) + t_iter
            h01 = (-2*(t_iter**3)) + ( 3*(t_iter**2))
            h11 = ( 1*(t_iter**3)) - ( 1*(t_iter**2))
            px = h00*p0.pos[0] + h10*m0[0] + h01*p1.pos[0] + h11*m1[0]
            py = h00*p0.pos[1] + h10*m0[1] + h01*p1.pos[1] + h11*m1[1]
            #pz = h00*p0.pos[2] + h10*m0[2] + h01*p1.pos[2] + h11*m1[2]
            Lines.append((px,py))
            t_iter += t_inc
        Lines.append((p1.pos[0],p1.pos[1]))
        Lines2 = []
        for p in Lines:
            Lines2.append((int(round(p[0])),Screen[1]-int(round(p[1]))))
            if save_points: interpolated_points.append((int(round(p[0])),int(round(p[1]))))
        pygame.draw.aalines(Surface,(255,255,255),False,Lines2)
        i += 1
def GetInput():
    global pressing, save_points
    key = pygame.key.get_pressed()
    mpress = pygame.mouse.get_pressed()
    mpos = pygame.mouse.get_pos()
    for event in pygame.event.get():
        if event.type == QUIT or key[K_ESCAPE]:
            pygame.quit(); sys.exit()
        if key[K_SPACE] and not save_points:
            save_points=True
            DrawCurve()
            SaveLines()
    if mpress[0]:
        if not pressing:
            pressing = True
            ControlPoints.append(ControlPoint((mpos[0],Screen[1]-mpos[1])))
    else:
        pressing = False
def Draw():
    Surface.fill((0,0,0))
    for cp in ControlPoints:
        pygame.draw.circle(Surface,(255,0,0),(cp.pos[0],Screen[1]-cp.pos[1]),2)
    if len(ControlPoints) >= 4:
        DrawCurve()
    pygame.display.flip()
def main():
    while True:
        GetInput()
        Draw()
if __name__ == '__main__': main()