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from OpenGL.GL import *
from OpenGL.GLUT import *
from OpenGL.GLU import *
import sys
import copy
from math import cos, sin
from ArcBall import * # ArcBallT and this tutorials set of points/vectors/matrix types
PI2 = 2.0*3.1415926535 # 2 * PI (not squared!) // PI Squared
# *********************** Globals ***********************
# Python 2.2 defines these directly
try:
True
except NameError:
True = 1==1
False = 1==0
g_Transform = Matrix4fT ()
g_LastRot = Matrix3fT ()
g_ThisRot = Matrix3fT ()
g_ArcBall = ArcBallT (640, 480)
g_isDragging = False
g_quadratic = None
# A general OpenGL initialization function. Sets all of the initial parameters.
def Initialize (Width, Height): # We call this right after our OpenGL window is created.
global g_quadratic
glClearColor(0.0, 0.0, 0.0, 1.0) # This Will Clear The Background Color To Black
glClearDepth(1.0) # Enables Clearing Of The Depth Buffer
glDepthFunc(GL_LEQUAL) # The Type Of Depth Test To Do
glEnable(GL_DEPTH_TEST) # Enables Depth Testing
glShadeModel (GL_FLAT); # Select Flat Shading (Nice Definition Of Objects)
glHint (GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST) # Really Nice Perspective Calculations
g_quadratic = gluNewQuadric();
gluQuadricNormals(g_quadratic, GLU_SMOOTH);
gluQuadricDrawStyle(g_quadratic, GLU_FILL);
# Why? this tutorial never maps any textures?! ?
# gluQuadricTexture(g_quadratic, GL_TRUE); # // Create Texture Coords
glEnable (GL_LIGHT0)
glEnable (GL_LIGHTING)
glEnable (GL_COLOR_MATERIAL)
return True
def Upon_Drag (cursor_x, cursor_y):
""" Mouse cursor is moving
Glut calls this function (when mouse button is down)
and pases the mouse cursor postion in window coords as the mouse moves.
"""
global g_isDragging, g_LastRot, g_Transform, g_ThisRot
if (g_isDragging):
mouse_pt = Point2fT (cursor_x, cursor_y)
ThisQuat = g_ArcBall.drag (mouse_pt) # // Update End Vector And Get Rotation As Quaternion
g_ThisRot = Matrix3fSetRotationFromQuat4f (ThisQuat) # // Convert Quaternion Into Matrix3fT
# Use correct Linear Algebra matrix multiplication C = A * B
g_ThisRot = Matrix3fMulMatrix3f (g_LastRot, g_ThisRot) # // Accumulate Last Rotation Into This One
g_Transform = Matrix4fSetRotationFromMatrix3f (g_Transform, g_ThisRot) # // Set Our Final Transform's Rotation From This One
return
def Upon_Click (button, button_state, cursor_x, cursor_y):
""" Mouse button clicked.
Glut calls this function when a mouse button is
clicked or released.
"""
global g_isDragging, g_LastRot, g_Transform, g_ThisRot
g_isDragging = False
if (button == GLUT_RIGHT_BUTTON and button_state == GLUT_UP):
# Right button click
g_LastRot = Matrix3fSetIdentity (); # // Reset Rotation
g_ThisRot = Matrix3fSetIdentity (); # // Reset Rotation
g_Transform = Matrix4fSetRotationFromMatrix3f (g_Transform, g_ThisRot); # // Reset Rotation
elif (button == GLUT_LEFT_BUTTON and button_state == GLUT_UP):
# Left button released
g_LastRot = copy.copy (g_ThisRot); # // Set Last Static Rotation To Last Dynamic One
elif (button == GLUT_LEFT_BUTTON and button_state == GLUT_DOWN):
# Left button clicked down
g_LastRot = copy.copy (g_ThisRot); # // Set Last Static Rotation To Last Dynamic One
g_isDragging = True # // Prepare For Dragging
mouse_pt = Point2fT (cursor_x, cursor_y)
g_ArcBall.click (mouse_pt); # // Update Start Vector And Prepare For Dragging
return
def Torus(MinorRadius, MajorRadius):
# // Draw A Torus With Normals
glBegin( GL_TRIANGLE_STRIP ); # // Start A Triangle Strip
for i in xrange (20): # // Stacks
for j in xrange (-1, 20): # // Slices
# NOTE, python's definition of modulus for negative numbers returns
# results different than C's
# (a / d)*d + a % d = a
if (j < 0):
wrapFrac = (-j%20)/20.0
wrapFrac *= -1.0
else:
wrapFrac = (j%20)/20.0;
phi = PI2*wrapFrac;
sinphi = sin(phi);
cosphi = cos(phi);
r = MajorRadius + MinorRadius*cosphi;
glNormal3f (sin(PI2*(i%20+wrapFrac)/20.0)*cosphi, sinphi, cos(PI2*(i%20+wrapFrac)/20.0)*cosphi);
glVertex3f (sin(PI2*(i%20+wrapFrac)/20.0)*r, MinorRadius*sinphi, cos(PI2*(i%20+wrapFrac)/20.0)*r);
glNormal3f (sin(PI2*(i+1%20+wrapFrac)/20.0)*cosphi, sinphi, cos(PI2*(i+1%20+wrapFrac)/20.0)*cosphi);
glVertex3f (sin(PI2*(i+1%20+wrapFrac)/20.0)*r, MinorRadius*sinphi, cos(PI2*(i+1%20+wrapFrac)/20.0)*r);
glEnd(); # // Done Torus
return
def Draw ():
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); # // Clear Screen And Depth Buffer
glLoadIdentity(); # // Reset The Current Modelview Matrix
glTranslatef(-1.5,0.0,-6.0); # // Move Left 1.5 Units And Into The Screen 6.0
glPushMatrix(); # // NEW: Prepare Dynamic Transform
glMultMatrixf(g_Transform); # // NEW: Apply Dynamic Transform
glColor3f(0.75,0.75,1.0);
Torus(0.30,1.00);
glPopMatrix(); # // NEW: Unapply Dynamic Transform
glLoadIdentity(); # // Reset The Current Modelview Matrix
glTranslatef(1.5,0.0,-6.0); # // Move Right 1.5 Units And Into The Screen 7.0
glPushMatrix(); # // NEW: Prepare Dynamic Transform
glMultMatrixf(g_Transform); # // NEW: Apply Dynamic Transform
glColor3f(1.0,0.75,0.75);
gluSphere(g_quadratic,1.3,20,20);
glPopMatrix(); # // NEW: Unapply Dynamic Transform
glFlush (); # // Flush The GL Rendering Pipeline
glutSwapBuffers()
return
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