我进行了一些修改以添加平方波。
在### HERE查看地点。
import sys, pygame, math
from pygame.locals import *
# set up a bunch of constants
WHITE = (255, 255, 255)
DARKRED = (128, 0, 0)
RED = (255, 0, 0)
BLACK = ( 0, 0, 0)
GREEN = ( 0, 255, 0) ### HERE
BLUE = ( 0, 0, 255) ### HERE
BGCOLOR = WHITE
WINDOWWIDTH = 640 # width of the program's window, in pixels
WINDOWHEIGHT = 480 # height in pixels
WIN_CENTERX = int(WINDOWWIDTH / 2) # the midpoint for the width of the window
WIN_CENTERY = int(WINDOWHEIGHT / 2) # the midpoint for the height of the window
FPS = 160 # frames per second to run at
AMPLITUDE = 80 # how many pixels tall the waves with rise/fall.
# standard pygame setup code
pygame.init()
FPSCLOCK = pygame.time.Clock()
DISPLAYSURF = pygame.display.set_mode((WINDOWWIDTH, WINDOWHEIGHT))
pygame.display.set_caption('Trig Waves')
fontObj = pygame.font.Font('freesansbold.ttf', 16)
# variables that track visibility modes
showSine = True
showSquare = True ### HERE
pause = False
xPos = 0
step = 0 # the current input f
### HERE
posRecord = {'sin': [], 'square': []} # keeps track of the ball positions for drawing the waves
# making text Surface and Rect objects for various labels
### HERE
squareLabelSurf = fontObj.render('square', True, BLUE, BGCOLOR)
squareLabelRect = squareLabelSurf.get_rect()
sinLabelSurf = fontObj.render('sine', True, RED, BGCOLOR)
sinLabelRect = sinLabelSurf.get_rect()
instructionsSurf = fontObj.render('Press Q to toggle wave. P to pause.', True, BLACK, BGCOLOR)
instructionsRect = instructionsSurf.get_rect()
instructionsRect.left = 10
instructionsRect.bottom = WINDOWHEIGHT - 10
### HERE
yPosSquare = AMPLITUDE # starting position
# main application loop
while True:
# event handling loop for quit events
for event in pygame.event.get():
if event.type == QUIT or (event.type == KEYUP and event.key == K_ESCAPE):
pygame.quit()
sys.exit()
# check for key presses that toggle pausing and wave visibility
if event.type == KEYUP:
if event.key == K_q:
showSine = not showSine
elif event.key == K_p:
pause = not pause
# fill the screen to draw from a blank state
DISPLAYSURF.fill(BGCOLOR)
# draw instructions
DISPLAYSURF.blit(instructionsSurf, instructionsRect)
# sine wave
yPos = -1 * math.sin(step) * AMPLITUDE
posRecord['sin'].append((int(xPos), int(yPos) + WIN_CENTERY))
if showSine:
# draw the sine ball and label
pygame.draw.circle(DISPLAYSURF, RED, (int(xPos), int(yPos) + WIN_CENTERY), 10)
sinLabelRect.center = (int(xPos), int(yPos) + WIN_CENTERY + 20)
DISPLAYSURF.blit(sinLabelSurf, sinLabelRect)
# draw the waves from the previously recorded ball positions
if showSine:
for x, y in posRecord['sin']:
pygame.draw.circle(DISPLAYSURF, DARKRED, (x, y), 4)
### HERE - drawing horizontal lines
# square
posRecord['square'].append((int(xPos), int(yPosSquare) + WIN_CENTERY))
if showSquare:
# draw the sine ball and label
pygame.draw.circle(DISPLAYSURF, GREEN, (int(xPos), int(yPosSquare) + WIN_CENTERY), 10)
squareLabelRect.center = (int(xPos), int(yPosSquare) + WIN_CENTERY + 20)
DISPLAYSURF.blit(squareLabelSurf, squareLabelRect)
# draw the waves from the previously recorded ball positions
if showSquare:
for x, y in posRecord['square']:
pygame.draw.circle(DISPLAYSURF, BLUE, (x, y), 4)
# draw the border
pygame.draw.rect(DISPLAYSURF, BLACK, (0, 0, WINDOWWIDTH, WINDOWHEIGHT), 1)
pygame.display.update()
FPSCLOCK.tick(FPS)
if not pause:
xPos += 0.5
if xPos > WINDOWWIDTH:
#sine ### HERE
xPos = 0
posRecord['sin'] = []
step = 0
# square ### HERE
yPosSquare = AMPLITUDE
posRecord['square'] = []
else:
#sine ### HERE
step += 0.008
#step %= 2 * math.pi
# square ### HERE
# jump top and bottom every 100 pixels
if xPos % 100 == 0:
yPosSquare *= -1
# add vertical line
for x in range(-AMPLITUDE, AMPLITUDE):
posRecord['square'].append((int(xPos), int(x) + WIN_CENTERY))
