import sys, time, math, os
import Image
from OpenGL.GL import *
from OpenGL.GLU import *
from OpenGL.GLUT import *

startDir = os.getcwd()

useMipmap = False

viewDistance = 25.0
viewRotY = 0.0
viewRotX = 0.0
viewDistanceVel = 0.0
viewRotXVel = 0.0
viewRotYVel = 0.0
prevTime = time.time()

textureID1 = 0
textureID2 = 0



def initTexture(filename):
    img = Image.open(filename)
    img = img.transpose(Image.FLIP_TOP_BOTTOM)
    global textureID1, textureID2

    textureID1 = glGenTextures(1)
    glBindTexture(GL_TEXTURE_2D, textureID1)
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT)
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT)
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR)
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR)
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, img.size[0], img.size[1],
                 0, GL_RGB, GL_UNSIGNED_BYTE, img.tostring())
    glBindTexture(GL_TEXTURE_2D, 0)

    textureID2 = glGenTextures(1)
    glBindTexture(GL_TEXTURE_2D, textureID2)
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT)
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT)
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR)
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST_MIPMAP_NEAREST)
    gluBuild2DMipmaps(GL_TEXTURE_2D, GL_RGB, img.size[0], img.size[1],
                 GL_RGB, GL_UNSIGNED_BYTE, img.tostring())
    glBindTexture(GL_TEXTURE_2D, 0)


def draw():
    glClearColor(0.5, 0.5, 0.5, 0)
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)
    
    glMatrixMode(GL_PROJECTION)
    glLoadIdentity()
    gluPerspective(50.0, 1.0, 1.0, 1000.0)
    glMatrixMode(GL_MODELVIEW)

    glLoadIdentity()
    glTranslatef(0.0, -1.0, -viewDistance)
    glRotatef(viewRotX, 1.0, 0.0, 0.0)
    glRotatef(viewRotY, 0.0, 1.0, 0.0)

    glEnable(GL_TEXTURE_2D)
    if useMipmap:
        glBindTexture(GL_TEXTURE_2D, textureID2)
    else:
        glBindTexture(GL_TEXTURE_2D, textureID1)

    glColor3f(1, 1, 1)
    glBegin(GL_QUADS)

    glTexCoord2f(0, 0)
    glVertex3f(-5, -5, 0)

    glTexCoord2f(2, 0)
    glVertex3f(5, -5, 0)

    glTexCoord2f(2, 2)
    glVertex3f(5, 5, 0)

    glTexCoord2f(0, 2)
    glVertex3f(-5, 5, 0)

    glEnd()

    glDisable(GL_TEXTURE_2D)

    if useMipmap:
        drawLabel("GL_LINEAR_MIPMAP_LINEAR")
    else:
        drawLabel("GL_LINEAR")

    glutSwapBuffers()

    
def drawLabel(label):
    glDisable(GL_DEPTH_TEST)
    glMatrixMode(GL_PROJECTION)
    glLoadIdentity()
    gluOrtho2D(0.0, 1.0, 0.0, 1.0)
    glMatrixMode(GL_MODELVIEW)
    glLoadIdentity()
    glColor3f(0, 0, 0)
    glRasterPos2f(0.1, 0.05)
    for c in label:
        glutBitmapCharacter(GLUT_BITMAP_TIMES_ROMAN_24, ord(c))
    glEnable(GL_DEPTH_TEST)




def keyboard(key, x, y):
    global viewDistanceVel, useMipmap
    if key == chr(27):
        sys.exit(0)
    elif key == '.':
        viewDistanceVel -= 10
    elif key == ',':
        viewDistanceVel += 10
    elif key == ' ':
        useMipmap = not useMipmap

def keyboardUp(key, x, y):
    global viewDistanceVel
    if key == '.':
        viewDistanceVel += 10
    elif key == ',':
        viewDistanceVel -= 10

def specialkey(key,x,y):
    global viewRotXVel, viewRotYVel
    if key == GLUT_KEY_LEFT:
        viewRotYVel += 90
    elif key == GLUT_KEY_RIGHT:
        viewRotYVel -= 90
    elif key == GLUT_KEY_UP:
        viewRotXVel += 90
    elif key == GLUT_KEY_DOWN:
        viewRotXVel -= 90

def specialkeyUp(key,x,y):
    global viewRotXVel, viewRotYVel
    if key == GLUT_KEY_LEFT:
        viewRotYVel -= 90
    elif key == GLUT_KEY_RIGHT:
        viewRotYVel += 90
    elif key == GLUT_KEY_UP:
        viewRotXVel -= 90
    elif key == GLUT_KEY_DOWN:
        viewRotXVel += 90

def update():
    global viewRotX, viewRotY, viewRotXVel, viewRotYVel, viewDistance, viewDistanceVel
    global prevTime
    t = time.time()
    dt = t - prevTime
    prevTime = t
    viewRotX += viewRotXVel * dt
    viewRotY += viewRotYVel * dt
    viewDistance += viewDistanceVel * dt
    glutPostRedisplay()

glutInit([])
glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH)
glutInitWindowSize(400,400)
glutCreateWindow(sys.argv[0])
glutDisplayFunc(draw)
glutKeyboardFunc(keyboard)
glutKeyboardUpFunc(keyboardUp)
glutSpecialFunc(specialkey)
glutSpecialUpFunc(specialkeyUp)
glutIgnoreKeyRepeat(1)
glutIdleFunc(update)
glEnable(GL_DEPTH_TEST)
os.chdir(startDir)
if len(sys.argv) > 1:
    initTexture(sys.argv[1])
else:
    initTexture("spacetunnel.tiff")
glutMainLoop()