homeworkComputer Graphics

ECE 595 Computer Graphics Assignment 2
Question 1:
To emphasize the importance of understanding how the order of transformations influences the way a model is moved in the world. Consider the following three transformations:
glRotatef (30.0, 0.0, 1.0, 0.0);
glRotatef (45.0, 0.0, 0.0, 1.0);
glTranslatef (0.0, 0.0, -0.5);
There are six possible orderings of the above commands. Discuss the position of the teapot in the scene if glutSolidTeapot()were executed as a final command in each of the six cases. Write a simple OpenGL program to see the exact results.
Question 2:
1.Write an OpenGL program to display a teapot in the middle of the window with
appropriate gluLookAt(…) and glPerspective(…).
2.Implement two commands yourself: myPerspective(…) and myLookat(…) just like
gluPerspective(…) and gluLookAt(…) and display a teapot in the middle of the window.
3.Revise the program in step 2 by adding a flexible camera control option for user to slide,
pitch, roll or yaw the camera.
Question 3:
Write a program to perform a scan line polygon fill algorithm. Fill the following polygon with the implemented seed fill algorithm.
e the key X to control the filling pixel by pixel, or
2.Implement the pixel fill procedure with animation.
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Question 4:
The program must be able to load 3D models provided in "bunny.poly" format. This format is: number of vertices, number of polygons, a list of vertices, and a list of polygons expressed as indices into the list of vertices. The most important thing to notice about the .poly format is that the indices of vertices (references by the list of faces) start at 1, not 0.
•The user must be able to rotate and zoom the view around the center of the model (may not equal the origin).
•There must be a toggle allowing the user to switch between four different clipping modes: o No clipping
o Use OpenGL's built-in support for arbitrary clipping planes to perform the clipping.
o Use the plane equations to determine which polygons intersect the planes (and so would be divided), and change the color of these polygons so they can be easily
seen.
o Use the Sutherland-Hodgeman algorithm to clip all polygons that penetrate, or fall within, the negative half spaces of either (or both) of the clipping planes. If a
polygon is partially clipped, compute the new polygon that is within the positive
half space. Also, make an executive decision to either render n-sided polygons or
to convert all n-gons into triangles before rendering (we promise that all incoming
polygons will be convex).
•Add a toggle that switches between solid and wireframe shading.
•Implement a way of directly editing the A, B, C, and D values for each of the two plane equations (e.g. the user presses a key in GLUT and then types the equations into the
windows console).
•Implement a method of rotating/sliding the clipping planes around with mouse and/or keyboard controls, in addition to the manual entry.
Notes: Provide source code listings, with documentation explaining what your code does.。