Merge pull request #794 from nature-of-code/notion-update-docs

Beginning of Chapter 3 layout

content/03_oscillation.html

@@ -20,9 +20,9 @@ <h3 id="gala-by-bridget-riley-1974-acrylic-on-canvas-1597--1597-cm">Gala by Brid
 <p>To model oscillation, you need to understand a little bit about <strong>trigonometry</strong>, the mathematics of triangles. Learning some trig will give you new tools to generate patterns and create new motion behaviors in a p5.js sketch. You’ll learn to harness angular velocity and acceleration to spin objects as they move. You’ll be able to use the sine and cosine functions to model nice ease-in, ease-out wave patterns. You’ll also learn to calculate the more complex forces at play in situations that involve angles, such as a pendulum swinging or a box sliding down an incline.</p>
 <p>I’ll start with the basics of working with angles in p5.js, then cover several aspects of trigonometry. In the end, I’ll connect trigonometry with what you learned about forces in <a href="/forces#">Chapter 2</a>. This chapter’s content will pave the way for more sophisticated examples that require trig later in this book.</p>
 <h2 id="angles">Angles</h2>
-<p>Before going any further, I need to make sure you understand how the concept of an <strong>angle</strong> fits into creative coding in p5.js. If you have experience with p5.js, you’ve undoubtedly encountered this issue while using the <code>rotate()</code> function to rotate and spin objects.</p>
+<p>Before going any further, I need to make sure you understand how the concept of an <strong>angle</strong> fits into creative coding in p5.js. If you have experience with p5.js, you’ve undoubtedly encountered this issue while using the <code>rotate()</code> function to rotate and spin objects. You’re most likely to be familiar with the concept of an angle as measured in <strong>degrees</strong> (see Figure 3.1).</p>
 <figure>
-  <img src="images/03_oscillation/03_oscillation_2.png" alt="Figure 3.1: Angles measured in degrees">
+  <img src="images/03_oscillation/03_oscillation_2.jpg" alt="Figure 3.1: Angles measured in degrees">
   <figcaption>Figure 3.1: Angles measured in degrees</figcaption>
 </figure>
 <div class="half-width-right">
@@ -31,7 +31,7 @@ <h2 id="angles">Angles</h2>
     <figcaption>Figure 3.2: A square rotated by 45 degrees</figcaption>
   </figure>
 </div>
-<p>You’re most likely to be familiar with the concept of an angle as measured in <strong>degrees</strong> (see Figure 3.1). A full rotation goes from 0 to 360 degrees, and 90 degrees (a right angle) is one-fourth of 360, shown in Figure 3.1 as two perpendicular lines.</p>
+<p>A full rotation goes from 0 to 360 degrees, and 90 degrees (a right angle) is one-fourth of 360, shown in Figure 3.1 as two perpendicular lines.</p>
 <p>Angles are commonly used in computer graphics to specify a rotation for a shape. For example, the square in Figure 3.2 is rotated 45 degrees around its center.</p>
 <div class="half-width-right">
   <figure>