import pygame from kingdon import Algebra import math ERROR = 0.00001 DISK_RADIUS = 250 WIDTH, HEIGHT = 800, 600 CENTER_X, CENTER_Y = 400, 300 alg = Algebra(2,1,0) locals().update(alg.blades) def point(x,y): #Construct a point. #Hyperbolic space is modeled as a hyperboloid embedded in 3D Minkowski space. #Find w such that x,y,w is a point on the hyperboloid. w_sqr = x*x + y*y + 1 w = math.sqrt(w_sqr) return x*e23 -y*e13 + w*e12 def draw_point(point): #Normalize the point x_0 = point.e12 x_1 = -point.e23 x_2 = point.e13 norm = math.sqrt(x_0*x_0 - x_1*x_1 - x_2*x_2) x_0 = x_0/norm x_1 = x_1/norm x_2 = x_2/norm #Transform it into the Poincare Space u = x_1/(1+x_0) v = x_2/(1+x_0) pygame.draw.circle(screen, RED, (int(u*DISK_RADIUS+CENTER_X), int(v*DISK_RADIUS+CENTER_Y)), 5) def draw_line(line): delta = line.e3 if abs(delta) < ERROR: # The geodesic is a line through the origin. if abs(line.e2) < ERROR: pygame.draw.line(screen, BLUE, (CENTER_X, CENTER_Y+DISK_RADIUS), (CENTER_X, CENTER_Y-DISK_RADIUS), 1) else: slope = line.e1/line.e2 pygame.draw.line(screen, BLUE, (CENTER_X-DISK_RADIUS, int(CENTER_Y-slope*DISK_RADIUS)), (CENTER_X+DISK_RADIUS, int(CENTER_Y+slope*DISK_RADIUS)), 1) else: #The geodesic is a circle a = line.e1 b = line.e2 sqr = a*a + b*b norm = math.sqrt(sqr) x_c = a/delta y_c = b/delta r = math.sqrt(x_c*x_c+y_c*y_c - 1) c_x = int(CENTER_X + x_c*DISK_RADIUS) c_y = int(CENTER_Y + y_c*DISK_RADIUS) pygame.draw.circle(screen, BLUE, (c_x, c_y), int(r*DISK_RADIUS), 1) y_axis = e1 #x = 0 line x_axis = e2 #y = 0 line tx_generator = e13 #A translation in the x direction ty_generator = e23 #A translation in the y direction origin = e12 #The origin, and a rotation about the origin # Initialize Pygame pygame.init() screen = pygame.display.set_mode((WIDTH, HEIGHT)) pygame.display.set_caption("Pygame Example") # Colors BLACK = (0, 0, 0) WHITE = (255, 255, 255) RED = (255, 0, 0) BLUE = (0, 0, 255) # Game loop running = True t = 0 while running: t += 0.0002 for event in pygame.event.get(): if event.type == pygame.QUIT: running = False # Clear the screen screen.fill(WHITE) #Poincare Disk Boundary pygame.draw.circle(screen, BLACK, (CENTER_X, CENTER_Y), DISK_RADIUS, 1) #Generate a transformation for demonstration transform = math.sin(t)*tx_generator + math.sin(math.sqrt(2)*t)*ty_generator + math.sin(math.sqrt(3)*t)*origin transform = transform motor = transform.exp() #Apply the transformation y_tick = motor*y_axis*motor.reverse() x_tick = motor*x_axis*motor.reverse() #Construct a point as the intersection of the two lines point = y_tick^x_tick #Draw everything draw_line(y_tick) draw_line(x_tick) draw_point(point) tx = tx_generator.exp() ty = ty_generator.exp() point_a = tx*ty*origin*ty.reverse()*tx.reverse() point_b = ty*tx*origin*tx.reverse()*ty.reverse() draw_line(x_axis) draw_line(y_axis) draw_point(origin) draw_point(point_a) draw_point(point_b) # Update the display pygame.display.flip() # Quit Pygame pygame.quit()