CS148 Program 2 FAQ

Project 2 FAQ

Q: Do you have any tips that didn't fit well into the question/answer paradigm of this page?
A: Why yes, curious reader, we do!
You will save yourself some confusion if you only use glScalef to draw objects, then pop the scale off the stack immediately after you're finished drawing and not let it affect your current reference frame. It's very confusing when your translations are scaled, and it's nice to be able to keep in your head the rough numbers that should correspond to the size of a robot part, which scales can mess up.
So if I want to draw a squashed cube, I should probably do something like:
```
glPushMatrix();
  glScalef(0.3,1.0,1.0);
  glutSolidCube(0.5);
glPopMatrix();
```
Q: Is drawing the different body parts just a matter of guess and check, screwing with the numbers until they look about right?
A: Indeed. In fact much of graphics programming is doing exactly that. :)
With that said, we don't recommend typing random numbers in and changing them until it looks right. You will make your life easier if you use constants like TOBOR_ARM_LENGTH instead of putting numbers in your code. That way when you need to draw a segment with some length _and_ translate the frame by the same amount for the next segment, you can just use your constant. Plus most of those numbers you use on both sides of the body anyway, so having a #define is convenient.
Q: Do I need to be fancy with the body, or can I just draw one big cube for the torso, and just the basics in terms of arms/legs/head?
A: You don't need to be fancy, as long as all the segments are visible and they appear to connect at the joints around which they rotate (i.e. 9 rectangles spinning randomly in space does not a TOBOR make).

We'll give 2 points of extra credit to the nicest-looking TOBOR in the class, with the possibility of an n-way tie if the judges have a tough time with it.