Lecture: Dots

Dear students:

You made it back for a second day of CS 488. Me too. You read about how to draw points and lines with WebGL and set up your first renderer. We will revisit those ideas as we walk through the process of building a renderer. You should definitely ask questions. I'll start with some of my own.

Questions

One of the things that's nice about not being in school is that you start to ask yourself questions. School puts you on the defense, but once you graduate, you get to go on the offense. And you start to feel like you're learning. Nonetheless, school is where we often learn to ask questions. Here are a few that I have after reading the chapter that I wrote.

1. What geometric primitive would I use to draw a 6 on a 7-segment display?
2. Where is \(\begin{bmatrix}0.5&-0.5\end{bmatrix}\) in the WebGL's native viewport?
3. What is a VBO? A VAO?
4. How do I express the color pink?
5. I have a vector \(\begin{bmatrix}a&b\end{bmatrix}\) of magnitude \(c\). How does the magnitude change if I double \(a\) and \(b\)?

Lost Vertex

Let's do another lost vertex exercise. Suppose you know that the shape is an isosceles triangle. But you only have two of its vertices:

Can you compute a third? What's an algorithm? We'll write a renderer to compute it and draw the triangle. We'll need a Vector3 class, vertex and fragment shaders, a vertex buffer, and a draw call.

Suppose you know that the shape is an equilateral triangle. Can you compute the third?

TODO

Here's your list of things to do before we meet next:

See you next time.