I wrote this code using Python 3.5 and Pygame to help me learn more about sine waves. Its goal is to show the variations in the sine and cosine values in the Trigonometry Circle as the distance covered by a point in the circumference increases.

I’d appreciate suggestions and advices about the code, specially about the math involved and my usage of Pygame.

Thanks.

import pygame import math  SCR_WIDTH = 220 SCR_HEIGHT = 480  RAD_SIZE = 100 CIRCLE_X = int(105) CIRCLE_Y = int(285)  STD_FONT_SZ = 25   def drawChart(frequency, time, turns, sin, cos, surface):     """Draws the frequency, time, distance, and sine and cosine values on the given surface"""      freq_txt = font.render("Frequency: {:.3}Hz".format(frequency), False, (0,0,0))     time_txt = font.render("Time: {:.3}s".format(time), False, (0,0,0))     turn_txt = font.render("Turns: {:.3}".format(turns), False, (0,0,0))     sin_txt = font.render("Sine: {:.3}".format(sin), False, (0,0,0))     cos_txt = font.render("Cosine: {:.3}".format(cos), False, (0,0,0))      surface.blit(time_txt,(0,0))     surface.blit(freq_txt,(0,STD_FONT_SZ))     surface.blit(sin_txt,(0,STD_FONT_SZ*2))     surface.blit(cos_txt,(0,STD_FONT_SZ*3))     surface.blit(turn_txt,(0,STD_FONT_SZ*4))    def drawCircle(x,y, surface):     """Draws the Trigonometry circle on the given surface in position x, y"""      pygame.draw.line(surface,(0,0,0),(x-RAD_SIZE,y),(x+RAD_SIZE,y))  #x-axis       pygame.draw.line(surface,(0,0,0),(x,y-RAD_SIZE),(x,y+RAD_SIZE))  #y-axis     pygame.draw.circle(surface,(0,0,0), (x,y), RAD_SIZE, 1) #main circle     surface.blit(x_txt,(x+RAD_SIZE, y)) #x character     surface.blit(y_txt,(x,y-RAD_SIZE-STD_FONT_SZ-4)) #y character  pygame.init() pygame.display.set_caption("SineRep v. 1.0")  screen = pygame.display.set_mode((SCR_WIDTH, SCR_HEIGHT), 0, 32) font = pygame.font.SysFont("arial",STD_FONT_SZ)  frequency = 0.1  x_txt = font.render("x", False, (0,0,0)) y_txt = font.render("y", False, (0,0,0))  while True:     screen.fill((255,255,255))      time = pygame.time.get_ticks()/1000     distance = 2*math.pi*time*frequency     turns = time*frequency         cos = math.cos(distance)     sin = math.sin(distance)      #size of cosine and sine in pixels     cos_pxl = int(cos*RAD_SIZE)     sin_pxl = int(-sin*RAD_SIZE)       ##### Draw stuff in the screen     drawChart(frequency, time, turns, sin, cos, screen)     drawCircle(CIRCLE_X, CIRCLE_Y, screen)      pygame.draw.circle(screen,(255,0,0), (CIRCLE_X+cos_pxl,CIRCLE_Y+sin_pxl), 5, 0) #dot      #Auxiliary shapes     pygame.draw.circle(screen,(255,0,0), (CIRCLE_X+cos_pxl,CIRCLE_Y), 3, 1) #cosine dot       pygame.draw.circle(screen,(255,0,0), (CIRCLE_X,CIRCLE_Y+sin_pxl), 3, 1) #sine dot          pygame.draw.line(screen,(255,0,0),(CIRCLE_X,CIRCLE_Y),(CIRCLE_X+cos_pxl,CIRCLE_Y), 2)  #projection in x (cos)     pygame.draw.line(screen,(255,0,0),(CIRCLE_X,CIRCLE_Y),(CIRCLE_X,CIRCLE_Y+sin_pxl),2) #projection in y (sine)       event = pygame.event.poll()     if event.type == pygame.QUIT:         break      pygame.display.update()   pygame.quit()