# camera: take a picture, animate it on screen

import gst
import pippy
import pygame
import sys
import time

# grey background
bgcolor = (128, 128, 128)

# start using pygame
pygame.init()

# turn off cursor
pygame.mouse.set_visible(False)

# create the pygame window and return a Surface object for
# drawing in that window.
screen = pygame.display.set_mode((0, 0), pygame.FULLSCREEN)

# grab a frame from camera to file
pipeline = gst.parse_launch('v4l2src ! ffmpegcolorspace ! jpegenc ! filesink location=/tmp/pippypic.jpg')
pipeline.set_state(gst.STATE_PLAYING)

# keep trying to load in the grabbed camera frame until it works
while True:
  try:
    image = pygame.image.load('/tmp/pippypic.jpg')
    break
  except pygame.error:
    time.sleep(1)

# stop the camera frame grabbing
pipeline.set_state(gst.STATE_NULL)

# set initial rotation angle and scale
angle = 0.0
scale = 2.0

while pippy.pygame.next_frame():
    # every time we animate, check for quit or keydown events and exit
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            sys.exit()
        elif event.type == pygame.KEYDOWN:
            sys.exit()

    # rotate and scale the image
    newImage = pygame.transform.rotozoom(image, angle, scale)
    newImageRect = newImage.get_rect()
    newImageRect.centerx = screen.get_rect().centerx
    newImageRect.centery = screen.get_rect().centery

    # display the rotated and scaled image
    screen.fill(bgcolor)
    screen.blit(newImage, newImageRect)
    pygame.display.flip()

    # choose a new rotation angle and scale
    angle = angle + 5.0
    scale = scale * 0.95

    # finish once the scale becomes very very small
    if scale < 0.001:
        break
