import sys, time, math, array
from OpenGL.GL import *
from OpenGL.GLU import *
from OpenGL.GLUT import *
from dmsgl import *
import videoInput

videoWidth, videoHeight = 320,240
videoScale = 640/videoWidth
videoInput.openVideo("/dev/video", videoWidth, videoHeight)
prevFrame = videoInput.grabVideo()
imageArray = array.array('B')

showVideo = True

orthoCam = OrthoCamera(-0.5, videoWidth-0.5, -0.5, videoHeight-0.5, -1000, 1000)
#orthoCam = OrthoCamera(0, videoWidth, 0, videoHeight, -1000, 1000)

lastFrame = 90
lastFrameTime = time.time()

def draw():
    orthoCam.apply()

    glRasterPos2f(0, videoHeight-1)
    glPixelZoom(videoScale, -videoScale)
    if showVideo:
        glDrawPixels(videoWidth, videoHeight, GL_RGB, GL_UNSIGNED_BYTE, prevFrame)
    else:
        glDrawPixels(videoWidth, videoHeight, GL_LUMINANCE, GL_UNSIGNED_BYTE, imageArray.tostring())

    glutSwapBuffers()

    t = time.time()
    global lastFrame, lastFrameTime
    if lastFrame % 100 == 0:
        print t-lastFrameTime, ' -> ', 1.0/(t-lastFrameTime), 'fps'
    lastFrame = (lastFrame+1)%100
    lastFrameTime = t

def checkVideo():
    global imageArray, prevFrame
    frame = videoInput.grabVideo()
    if len(imageArray)>0: del imageArray[0:len(imageArray)]
    for i in range(0,len(frame),3):
        if abs(ord(frame[i]) - ord(prevFrame[i])) < 64:
            imageArray.append(0)
        else:
            imageArray.append(255)
    prevFrame = frame


def update():
    checkVideo()
    glutPostRedisplay()


def keyboard(key, x, y):
    global showVideo
    if key == chr(27):
        sys.exit(0)
    elif key == ' ':
        showVideo = not showVideo


glutInit([])
glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE)
glutInitWindowSize(videoWidth*videoScale, videoHeight*videoScale)
glutCreateWindow(sys.argv[0])
glutDisplayFunc(draw)
glutKeyboardFunc(keyboard)
glutIdleFunc(update)
glutMainLoop()