CS559 Course News

Either later today or Wednesday I will email everyone with their Project 3 grade, their final exam score and grade, and their unofficial final grade. (I am not allowed to tell you your official final grade, only the registrar can do that).

I want to get them sent out today, but I'm not sure I will get them all done.

Yu-Chi has the exams and the Project 3 score sheets, so if you have questions about them, please ask me after January 8th (since I will be traveling and he will be traveling).

The answer key to the final exam is posted here.

Mean score = 64.3 Median score = 61

I tried two grading systems: one was the "it was a hard semester, give everyone a Holiday Gift" scale

A > 78, AB > 64, B > 55, BC > 48, low scores gvein C

The other was the "how it really should be graded" scale:

A >= 90, AB >= 80(*), B >= 65, BC >=55, C >= 51, CD >= 43, D >= 40 In all 32 exams, only 1 person was "on the fence" so I gave them the extra point (*).

What's amazing about this is that switching between these two grading systems give very different final exam scores, but did not change anyone's grades. (Actually, its not so amazing, the final doesn't count for much. And we were very generous with the grades for the Assignments - 2/3s of the students got As.)

So I've chosen to use the harsher scale. That way, I can feel like the exam was graded fairly. Your exam grade indicates how well you really did on the final. And no one's permanent record is affected.

Overall, the class grades were very good. The mean and median grade is an AB! (I don't mind the final grades being so high - this is a hard class, and you've all put in a lot of effort.)

A reminder: The final exam will be at 12:25pm on Thursday, December 22th, in room 1325 CS.

The exam is cumulative - it will cover topics from the entire course, although there will be an emphasis on topics discussed in class after the midterm.

Is posted here.

Note: there are some cases where I gave "more correct" answers than the student did. For the purposes of the homework, the answers given were fine.

And thanks to Mohamed for writing up his answers so nicely and allowing me to share them.

Some of you have had some problems using "new" OpenGL features on the CSL machines. Multi-texturing is one example.

The OpenGL libraries on the Storm machines should be up to date (although, some people have had some problems that we are looking in to). However, the header files defining the new functions are missing.

For now, you can try including the "glext.h" header in your project. We have put a copy at http://www.cs.wisc.edu/graphics/Courses/559-f2005/SampleCode/glext.h. There is a chance that this might not work.

Just using a better header doesn't help. The correct solution is to use an extension manager that determines what the driver is capable of and provides access accordingly. If at this late of a date you're still trying to figure this out, you're probably in trouble.

The signup sheet is posted outside of Yu-Chi's door. I will also bring it to class on Thursday.

Just to be clear: an articulation is when two pieces of an object move relative to one another - like a hinge. To move an articulation means to make one piece move relative to the other. So, a windmill is an articulated figure and having it spin around would be moving the articulation.

There is a subtle bug in the P3 Sample code: If a car starts out in an intersection, it gets confused (since the direction it leaves an intersection depends on the direction it came from, so if it didn't have a from direction...).

By an amazing random chance (I think its about 1 in a million), this never happened because the random placement of cars in the example program never put one in the intersection. If you added more cars, or if you re-seeded the random number generator, you won't be so lucky.

The easiest solution is to avoid placing cars in intersections. I did this by changing my "main" routine to include the following (this is inside the loop that makes the cars):

// we need to pick a road to start on...
Road* startRoad = 0;
do {
   startRoad = theRoads[rand() % theRoads.size()];
} while (startRoad->is_intersection);
new RandomDrive(c,startRoad,.2f,rand() % 2);

Because of the tight timeline (projects must be graded by the end of the semester), there will be no opportunity for "very late" projects. All projects are due at 1pm on Friday the 16th.

For the 19 students who have turned in their previous projects on time, there is of course no late penalty for this project (as you have saved your one free late project for this one).

For the rest of you, we would prefer that you focused on making a good project rather than turning it in on Tuesday morning. We will not assess the full half-grade penalty for projects turned in between Tuesday 9:30 (the original due date) and 1pm Friday.

In fairness to the people who have turned their previous assignments in on time, we will take lateness into consideration into our evaluation of Project 3. Because every Project 3 is different it is difficult to to assign a specific number, but the penalties will always be less than half of a letter grade.

If you prefer to turn your Project 3 in "on time" (e.g. by 9:30am Tuesday) so it is not considered late you may. Please notify Yu-Chi as soon as possible that you are choosing this option. Also, note that the late penalty will be smaller than a half letter grade, so it is probably worthwhile for you to take the extra time.

Previous grades are not be affected by this adjustment: it applies only to Project 3.

Will occur Friday afternoon, December 16th between 1 and 5 (more specific details to be given later). Note: this means that no projects can be accepted after 1pm on December 16th.

We'll do course evals in class next Tuesday (the 13th). The lecture will be first (on computer animation) and we'll leave some time for you to grade me.

There may be some opportunities to do graphics/visual computing projects both within the graphics group and with other groups around campus. If you're interested, please let us know.

There is a bug in the GrTown sample code. You might notice that once the lights go on, all drawing gets messed up.

The problem is that in cars.cpp, blending is turned on to draw the headlights but never turned off. If you insert the line of code:

glDisable(GL_BLEND);

after the "glClearColor" line in Cars.cpp in the method Car::drawAfter, things will work correctly.

The second bug causes the street lights not to draw, and will also preclude any use of drawAfter in a hierarchical model. To fix it, replace the for loop around line 108 of TownViewWidget.cpp with the line:

     drawAfterObList(theObjects,&drst);

You can also remove the declaration of the variable g (since it will no longer be used).

Is posted here

The final exam will be on December 22nd at 12:25pm in Room 1325 Comp Sci. This should be a lot easier to find than the midterm room.

Links to some of the sample code (particularly for Texture Mapping) were broken. They have been fixed.

Note: the graphics town code is organized into subdirectories. When you unzip it, make sure to unzip the whole archive (so you get the proper directory structure).

Shaohua's slides from the rendering lecturer are available on the Lecture Notes page.

Project 2 Demos will be spread out around Thanksgiving. There will be slots: Monday the 21st (3-4:30), Tuesday the 22nd (4-5:30) and Tuesday the 29th (4-5:30). A signup sheet will be posted by Yu-Chi's office. Please try to sign up for one of the slots.