#!python
# -*- coding:utf8 -*-
#
# draw image by pygame_sdl2

try:
    import pygame_sdl2
    pygame_sdl2.import_as_pygame()
except:
    print "pygame_sdl2 not available"

import pygame
import pygame.image
# from pygame.locals import *

SCREEN_SIZE = (640, 480)

def main():
    pygame.init()
    screen = pygame.display.set_mode( SCREEN_SIZE, pygame.HWSURFACE | pygame.DOUBLEBUF )
    pygame.display.set_caption('draw image by pygame_sdl2')

    sysfont = pygame.font.SysFont(None, 64)
    textsurface = sysfont.render("Hello world", True, (255, 255, 255))
    
    bg = pygame.image.load('bg.png').convert()
    image = pygame.image.load('ufo.png').convert_alpha()

    x = 10
    y = 10
    dx = 2
    dy = 1
    bgx = 0
    clock = pygame.time.Clock()
    cnt = 0

    while True:
        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                return
            if (event.type == pygame.KEYDOWN and event.key  == pygame.K_ESCAPE):
                return

        if x + dx < 0 or x + dx + image.get_width() >= SCREEN_SIZE[0]:
            dx *= -1
        if y + dy < 0 or y + dy + image.get_height() >= SCREEN_SIZE[1]:
            dy *= -1
        x += dx
        y += dy
        bgx -= 3
        if bgx < -640:
            bgx = 0
        
        # draw bg image
        screen.blit(bg, (bgx,0))
        screen.blit(bg, (bgx + SCREEN_SIZE[0],0))
        
        screen.blit(image, (x, y))        # draw image
        screen.blit(textsurface, (0, 0))  # draw text image
        
        # pygame.display.update()
        pygame.display.flip()
        
        clock.tick(60)  # 60fps
        
        cnt += 1
        if cnt % 180 == 0:
            print str(clock.get_fps()) + " FPS"

if __name__ == '__main__':
    main()