Thank you for your replies: Dan, Greg, Inigo, and Ian
I changed the sound buffer size and it helped a lot. I verified that there
was no empty space in the loop with Audacity. I changed the program to queue
the next sound on the key press events and play the queued sound when the
previous sound ends. This way there is less chance for weird uneven drum
loops. My long term goal is to replace the key press events with Midi
events.
Here is my updated code ( from the terminal "export SDL_AUDIODRIVER=pulse &&
python -u sampler.py")
#----------------------------------------------------------
import pygame
from pygame.locals import *
from sys import exit
pygame.mixer.pre_init(44100,-16,2,2048)
pygame.init()
#pygame.mixer.set_reserved(1)
reserved_channel_0 = pygame.mixer.Channel(0)
sound1 = pygame.mixer.Sound("beat1.wav")
sound2 = pygame.mixer.Sound("beat2.wav")
sound3 = pygame.mixer.Sound("beat3.wav")
sound4 = pygame.mixer.Sound("beat4.wav")
green = (138,226,52)
blue = (114,159,207)
black = (46,52,54)
white = (238,238,236)
pygame.display.set_caption("badp3nn1 sampler")
my_font = pygame.font.SysFont("Arial",32)
SCREEN_SIZE = (400, 300)
screen = pygame.display.set_mode(SCREEN_SIZE, RESIZABLE, 32)
TRACK_END = USEREVENT + 1
reserved_channel_0.set_endevent(TRACK_END)
def updateScreenAndQueueNextSound():
if reserved_channel_0.get_busy() == False:
print "Channel is not busy"
reserved_channel_0.queue(nextsound)
screen.fill(blue)
screen.blit(my_font.render("Change Queued",True,white),(0,0) )
pygame.display.update()
while True:
for event in pygame.event.get():
if event.type == KEYDOWN:
if event.key == K_UP:
nextsound = sound1
updateScreenAndQueueNextSound()
elif event.key == K_DOWN:
nextsound = sound2
updateScreenAndQueueNextSound()
elif event.key == K_LEFT:
nextsound = sound3
updateScreenAndQueueNextSound()
elif event.key == K_RIGHT:
nextsound = sound4
updateScreenAndQueueNextSound()
elif event.type == TRACK_END:
reserved_channel_0.queue(nextsound)
screen.fill(green)
screen.blit(my_font.render("Looping",True,black),(0,0) )
pygame.display.update()
elif event.type == QUIT:
exit()
#----------------------------------------------------------
On Sun, Dec 12, 2010 at 6:34 PM, Greg Ewing <[email protected]>wrote:
> Brian Gryder wrote:
>
> There is a noticeable lag between the key press events and the sound
>> changes.
>>
>
> Have you tried reducing the size of the sound buffer? It seems
> that the pygame mixer can only start a sound on a buffer
> boundary, so for accurate sound timing you need quite a small
> buffer size.
>
> --
> Greg
>
