1. Write down a Python program to draw a transformed triangle in a 2D space.
A. Set the window title to your student ID and the window size to (480,480).
B. Complete the render() function below to draw a triangle in the manner described in C.
i. You have to use OpenGL transformation functions. Do not use numpy matrix multiplication for composing transformations.
def render():
glClear(GL_COLOR_BUFFER_BIT)
glLoadIdentity()
# draw cooridnates
glBegin(GL_LINES)
glColor3ub(255, 0, 0)
glVertex2fv(np.array([0.,0.])) glVertex2fv(np.array([1.,0.]))
glColor3ub(0, 255, 0)
glVertex2fv(np.array([0.,0.])) glVertex2fv(np.array([0.,1.]))
glEnd()
glColor3ub(255, 255, 255)
drawTriangle()
###########################
# implement here
###########################
def drawTriangle():
glBegin(GL_TRIANGLES)
glVertex2fv(np.array([0.,.5])) glVertex2fv(np.array([0.,0.])) glVertex2fv(np.array([.5,0.]))
glEnd()
C.
If you press or repeat a key, the triangle should be transformed as shown in the Table:
Key
Q E
A D 1
Transformations should be accumulated (composed with previous one) unless you press ‘1’. i. You may need a global variable (like a python list object) to store key inputs.
|
Transformation |
|
Translate by -0.1 in x direction |
|
Translate by 0.1 in x direction |
|
Rotate by 10 degrees counterclockwise |
|
Rotate by 10 degrees clockwise |
|
Reset the triangle with identity matrix |
D.
E. Files to submit: A Python source file (Name the file whatever you want (in English). Extension should be .py)
F. Expected result:
When starts E*4 A *3
Q*6 D *2 1
2. Write down a Python program to draw rotating point p1=(0.5, 0), p2=(0, 0.5) and vector v1=(0.5, 0), v2=(0, 0.5) in a 2D space.
A. Set the window title to your student ID and the window size to (480,480).
B. Use the following render() and fill “# your implementation” parts to render p1,p2 and v1,v2.
- Hint: Render the vector v1, v2 as a line segment starting from the origin (0,0).
- Hint2: You need different translation matrix for p1 and p2 to render them correctly.
def render(th):
glClear(GL_COLOR_BUFFER_BIT)
glLoadIdentity()
# draw cooridnate
glBegin(GL_LINES)
glColor3ub(255, 0, 0)
glVertex2fv(np.array([0.,0.])) glVertex2fv(np.array([1.,0.]))
glColor3ub(0, 255, 0)
glVertex2fv(np.array([0.,0.])) glVertex2fv(np.array([0.,1.]))
glEnd()
glColor3ub(255, 255, 255)
# calculate matrix M1, M2 using th
# your implementation
# draw point p
glBegin(GL_POINTS)
# your implementation
glEnd()
# draw vector v
glBegin(GL_LINES)
# your implementation
glEnd()
C. Expected result: Uploaded LabAssignment4-2.mp4 i. Do not mind the initial angle.
- p1,p2 and v1,v2 should be -t rad rotated when t seconds have elapsed since the program was executed.
- You need to somehow combine a rotation matrix and a translation matrix to produce the expected result.
- Files to submit: A Python source file (Name the file whatever you want (in English). Extension should be .py)
