This is the CS559 (Computer
Graphics, Spring 2008) News and Announcements page.
check this page regularly for news and other announcements as this is one of the main
ways of spreading the word about class announcements. The other is our class
mailing list. You will be held accountable for
the information that appears on this page. This page will be updated frequently.
April 23, 2008
The final exam will be on Saturday, May 17th, 7:45-9:45AM,
COMP S&ST 1257
I mistakenly wrote
7:45-9:45PM on the course syllabus page at the beginning of this semester; sorry
for the confusion and now it's corrected. The timetable of the Registrar (http://timetable.doit.wisc.edu/cgi-bin/TTW3.navigate.cgi?20082+opensects/d266c559A1.html)
March 6, 2008
In the phase 2 of the
project 2, we provide some sample code for simple UI programming on the
On this page,
we have 3 Simple2D.cpp for downloading. The
third one has one line
When you build
this program (the third Simple2D.cpp), you may have the following link error
LINK : fatal error LNK1104: cannot open file
solution is to comment that line out and you will be fine. The program should
work correctly without that line.
Feb 26, 2008
1. What does
"post-multiply" mean in the stage1 of project 2?
It's the same
convention we used in class and OpenGL. If you say
then you will
get a matrix M*N. What "post" means is that N is multiplied
2. In question
7, what is the order of "composing a rotation and a uniform scale"?
Feb 13, 2008
1. What does "zero-centered" mean in stage 3 of project 1?
Let g = 1/5 [1 1 1 1 1]. This can mean different things.
One way to interpret it is: g(1)=g(2)=g(3)=g(4)=g(5)=1/5
and g is zero everywhere else.
By “zero centered”, it means g(-2)=g(-1)=g(0)=g(1)=g(2) = 1/5 and g is zeros
2. Correction of question 2 in the written assignment (stage 3) of project
WAS: 2.A The unit box (g(t) = 1 if
-.5 < t <= .5, 0 otherwise)
NEW: 2.A The unit box (g(t) = 1 if
-.5 <= t < .5, 0 otherwise)
WAS: 2.B ... Note: in the book, this is
the tent filter of r=1/2
NEW: 2.B ... Note: in the book, this
is the tent filter of r=1
WAS: 2.D The
tent of r=1
The tent of r=2
Feb 10, 2008
For the command
"chromakey" in project 1, you can assume that initially V has alpha = 255 for
Feb 1, 2008
For the "fill"
command, if the input region includes pixels that are outside the image, your
code should fill in the intersection of the image and the input region. If the
region is invalid, i.e., y2<y1 or x2<x1, you code does not need to do any job --
just leave the image as it is.
For the two
tutorials on alpha compositing, Alvy Ray Smith, "Image Compositing Fundamentals",
page 1-6 till the end of "premultiplication problems", is required; other
sections are optional. Tom Porter and Tom Duff "Compositing Digital
Images" is also optional.
the Photoshop issue, the deadline for Project 1
preliminary is extended to next Wednesday noon.
Jan 30, 2008
I updated the
reading material for week2, to include two
tutorials on alpha compositing.