Thursday, December 8, 2011

Nominate a Great TA for the SCS TA Excellence Award

With the last assignment marked and your projects coming in, I guess this pretty much wraps up our time together this term! It was awesome working with you and I hope I was able to be helpful to you all.

I wanted to draw your attention to the School of Computer Science's TA Excellence Award.  I started this with the admin staff a couple of years ago when I was the TA Mentor, and its success depends very much on you guys making meaningful nominations.  In the past, we've had lots of amazing comments from both students and profs so I hope this can continue this year, even though I've moved back into regular TA'ing and someone else has taken over the mentor role!

So, if you had a TA you really liked this term, or have a great one next term, please do consider nominating him or her.  (That includes me, if you happen to think I'm deserving!)

Nominate a great TA here

Best of luck on your exams, and hope you have an awesome second term! :D

Assignment 4 Marked

Everything should be in WebCT now.  Make sure to get back to me about any issues as soon as you can, since my baby is due December 24th and things only get more and more crazy until then. ;)  Thanks for your patience in getting this done!

Tuesday, November 29, 2011

Midterm 2 Marking Comments

The midterms are marked and the grades are in WebCT. Here are some comments on the way I marked them.

I must admit I had to go through these more quickly, so if you are unsure of why you lost marks somewhere because I didn't write much, let me know.  If you think your answer deserves more marks or that I missed something in determining the correctness of your answer, send an email that demonstrates this. If indeed I think you deserve more marks, I’ll ask you to bring in your midterm paper.

Be sure to check my addition!

Note: The prof said that as long as you didn’t go over the number of questions allowed for each section I could count all the marks for those questions, even if it takes you over 90. I am hoping this was clear for you during the exam, especially because this wasn't the case for the first one.

Number 1

In 1.1, I want to see specifics, especially what function is applied and what you do with the result of that function (add to the height of vertices). Being too general gets you 2/5. If you didn’t mention what the output of the wave function is doing you lost one mark.

In 1.2, the full formula is:
height = amplitude * sin (wavelength * distanceFromSource + angularFrequency*time + shift)
I am taking off 0.5 each for missing wavelength, angular frequency and shift and 1 for missing the others (amplitude, distance from source, and time). Same amount for missing or incorrect explanations. The height/sin part of the equation is worth 1 mark. If you added any terms that shouldn’t be there, I took off 0.5.

In 1.3, the idea is to find which source a particular wave is closer to – that will be the distance used to compute the vertex height. If you correctly did something that added the heights from the two waves together, we are giving marks (12/15).

Number 2

In 2.2, if you only talked about normals needing a proper transformation when transformations like shear are applied, you got 3/7. I needed to know what happens and why it matters in more detail (normals won’t be perpendicular, lighting will be wrong, etc).

Number 4

Forgetting to discuss 2-3 operations for the shaders will lose you 2 points each for 4.1 and 4.2.

Forgetting to state output for 4.1 and 4.2 loses you 1 mark.

Number 5

In 5.1, half marks are given for a reasonable discussion that shows a misunderstanding of the lighting components.

In 5.3, if you say that vertex shaders can be used to do bump mapping but don’t say how (as in, where are you going to get info on how to modify normals, such as from a texture), I took off 1 mark.

Number 6

In 6.1, getting the wrong R vector results in two marks lost (especially if I can’t see how you computed it).

In 6.3, if you forget the surface material value you lose 1 mark, and if you forget the source light you lose 1 mark. If you don’t normalize V and R you lose 1 mark.

Thursday, November 24, 2011

Ask Your Questions Today

Just a quick note to say that tomorrow, unfortunately, I will be in Toronto last-minute for a family illness and likely won't be able to answer your questions regarding the assignment.  So be sure to ask as much as you can today! Also, if enough of you could check WebCT through the day tomorrow, you may be able to help each other in the discussion forums.

Sorry about this!

Assignment 4 Clarification

I have confirmed a couple of things about the assignment that many of you were wondering about.  First of all, before starting task two, you should set the scaling of the earth object to be (1,1,1) again.  Answer all the questions up until 4.2 using this value.  Then change it to (0.1, 1, 0.1).  The question about what issue you observe and how to fix it is directly related to the midterm question on world inverse/tranpose matrix.  An answer of "don't scale it that way" is not correct, because of course you might actually want to scale it that way.  Think about what happens with the normals when you scale the sphere and whether they remain perpendicular to the surface.

Wednesday, November 23, 2011

Upcoming Grading Plans

Assignment 4

My first task is to actually do the assignment so that I can better answer some of your questions before it's due.  This will also make it easier to mark the midterm (and of course the assignment itself).  I am still waiting for confirmation about some of the issues you brought up regarding the assignment questions, and when I know more I will post here.

I will be grading the assignment after the midterms, so you probably won't see your mark back for these until the first full week of December or so.


The plan is to have the grades up on WebCT by the end of the day Tuesday November 29, which should be in time to decide to drop the course if needed.  Depending on exactly when I finish, you might get the papers back in class Tuesday, or Thursday at the latest.

Wednesday, November 16, 2011

The Best Midterm Tip I Can Give... to work on Assignment 4.  Trying to understand all the pieces and at least starting to code them will be invaluable.

Also be sure to have a good understanding of all the questions given as samples on the course webpage.

Remember, if you have any questions about any of these things, please ask sooner rather than later so I'll have time to give you a decent answer!