import sys, time, math
from OpenGL.GL import *
from OpenGL.GLU import *
from OpenGL.GLUT import *
from dmsgl import *
import os
startdir = os.getcwd() + os.sep

camera = PerspCamera()
camera.moveBackward(15)
rearCamera = PerspCamera()
rearCamera.aspect = 256.0 / 100.0

fog = Fog(mode=GL_LINEAR,start=60,end=200,color=Color.X11['DeepSkyBlue'])
light1 = Light()
light2 = Light()
light2.position = [-1, 1, -1, 0]
cow = WFObject(startdir+'cow.obj')
cowXform1 = SimpleTransform(translate=[3, 0, 0])
cowXform2 = SimpleTransform(translate=[-10, 0, -10], rotateAngle=45, rotateAxis=[0,1,0])
cowXform3 = SimpleTransform(translate=[-5, 0, 20], rotateAngle=160, rotateAxis=[0,1,0])

tex = Texture2D(startdir+'grass.jpg')


def drawWorld():
    Color.X11['DeepSkyBlue'].clear()
    fog.apply()
    light1.apply()
    light2.apply()

    cowXform1.pushApply()
    cow.draw()
    cowXform1.pop()
    cowXform2.pushApply()
    cow.draw()
    cowXform2.pop()
    cowXform3.pushApply()
    cow.draw()
    cowXform3.pop()

    tex.apply()
    glBegin(GL_QUADS)
    glTexCoord2f(0, 0)
    glVertex3f(-100, -3, -100)
    glTexCoord2f(1, 0)
    glVertex3f(100, -3, -100)
    glTexCoord2f(1, 1)
    glVertex3f(100, -3, 100)
    glTexCoord2f(0, 1)
    glVertex3f(-100, -3, 100)
    glEnd()
    tex.disable()

    fog.disable()

def draw():
    w = glutGet(GLUT_WINDOW_WIDTH)
    h = glutGet(GLUT_WINDOW_HEIGHT)
    glViewport(0, 0, w, h)
    glScissor(0, 0, w, h)
    camera.apply()
    drawWorld()

    glViewport(60, 300, 256, 100)
    glScissor(60, 300, 256, 100)
    rearCamera.apply()
    drawWorld()

    glutSwapBuffers()


def keyboard(key, x, y):
    global cameraVelDist
    if key == chr(27):
        sys.exit(0)
    elif key == '.':
        cameraVelDist += 4
    elif key == ',':
        cameraVelDist += -4

def keyboardUp(key, x, y):
    global cameraVelDist
    if key == chr(27):
        sys.exit(0)
    elif key == '.':
        cameraVelDist -= 4
    elif key == ',':
        cameraVelDist -= -4

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

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


cameraVelPitch = 0.0
cameraVelTurn = 0.0
cameraVelDist = 0.0
prevTime = time.time()

def update():
    global cameraVelPitch, cameraVelTurn, cameraVelDist
    global prevTime
    t = time.time()
    dt = t - prevTime
    prevTime = t
    camera.pitch(cameraVelPitch * dt)
    camera.turn(cameraVelTurn * dt)
    camera.moveForward(cameraVelDist * dt)
    rearCamera.position = camera.position
    rearCamera.xRot = camera.xRot
    rearCamera.yRot = camera.yRot + 180
    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)
glEnable(GL_SCISSOR_TEST)
glutMainLoop()