Errata¶

This page lists known errors in the text, which will be fixed in future versions. Thanks to those who reported errors, especially Larry Riddle of Agnes Scott College, who did a very thorough proofreading and is responsible for most of this list.

Chapter 2¶

Page 17¶

The text under Figure 2.6 is not consistent with Figure 2.6. The figure shows the computation $\vec v=Q-P=(4,-1)-(-1,2)=\langle 5,-3\rangle$ , but the text instead shows $\vec v=Q-P=(5,-1)-(1,2)=\langle 4,-3\rangle$ . The text should be changed to match the figure, using the first computation just shown, the one that produces $\langle 5,-3\rangle$ .

POV-Break A¶

Page 31¶

The text incorrectly states that it is not possible to have the full power of the Insert menu from POV-Ray for Windows if you use POV-Ray for Mac. There is a method for getting access to that Insert menu, and it is now documented on the Software Packages page.

Chapter 4¶

Page 95¶

Line 2: The word "into" is repeated twice.

Exercise 4.37 says "the while loop structure" when it should say "the for loop structure."

Chapter 5¶

Page 127¶

The first sentence of Exercise 5.23 says "any linear function," but it should say "any affine transformation of the plane." This is not relevant until part (e).

Page 156¶

Exercise 6.36 should not say "rotates the object about an arbitrary line in space," but rather "performs an ordinary POV rotation transformation centered on an arbitrary point in space." Then the example given makes more sense, and the exercise is less complex.

POV Break C¶

Page 159¶

The code block on this page is missing some curly brackets. The correct code block is shown here.

union {
  sphere { <-0.5,0,0>, 0.25 } // forms the left end cap of the pill
  sphere { < 0.5,0,0>, 0.25 } // forms the right end cap of the pill
  cylinder { <-0.5,0,0>, <0.5,0,0>, 0.25 } // the middle section
  pigment { color Wheat } // a predefined color, almost White
}

Page 166¶

The code block on this page is missing some affine transformations of the Doorstop. The correct code block is shown here; only the first two lines of the difference block have been changed.

#declare Cheese = difference {
  // Start with the doorstop defined earlier, repositioned:
  object { Doorstop scale 2.6 translate <-0.5,-0.35,1> }
  // Remove all of these objects to make holes:
  sphere { <0,-0.5,0>, 0.2 }
  sphere { <-0.75,-0.25,1.25>, 0.4 }
  sphere { <-0.8,-1,-0.3>, 0.3 }
  sphere { <-1.75,0.2,0.5>, 0.2 }
  sphere { <0.7,-1.1,1>, 0.3 }
  // Change its color to yellow:
  pigment { color BrightGold }
}

Chapter 7¶

Page 191¶

The first sentence of Exercise 7.14, as well as parts (a) and (b) should be referencing Exercise 7.13, not Exercise 7.10.

Page 192¶

In order for Exercises 7.17 and 7.18 to be consistent, we should alter Exercise 7.17 as follows.

In part (b), the cylinder endpoint $(0,h,0)$ should be $(0,0,h)$ .

In part (e), the cone endpoint $(0,h,0)$ should be $(0,0,h)$ .

Page 194¶

The cylinder in the center of Figure 7.16 has the wrong equations below it. They should read:

$x^2-z^2=\frac12$

$x^2-z^2-\frac12=0$
x*x-z*z-0.5

Chapter 8¶

Page 209¶

In Exercise 8.10, parts (b) and (c) were written incorrectly. They should be replaced with the following.

(b) To combine two RGB colors subtractively, first compute their CMY equivalents, combine them additively, and then convert the result back to an RGB vector. Redo each vector combination in Exercise 8.1, but this time use the procedure just described to combine them subtractively.

(c) Create a formula (the analog of (8.1)) for the subtractive combination of two RGB color vectors $\langle r_1,g_1,b_1\rangle$ and $\langle r_2,g_2,b_2\rangle$ .

Page 210¶

Exercise 8.13 should also contain this sentence: Assume in each case that $\langle h,1,1 \rangle$ corresponds to the RGB vector $\langle r,g,b \rangle$ and write your answers in terms of $r$ , $g$ , $b$ , and $p$ .

Chapter 10¶

Page 268¶

The equations above the graphs in Figure 10.7 should be $y=h_2(x)$ (for the left graph) and $y=h_3(x)$ (for the right graph).

Page 297¶

In Exercise 10.26, the hint is given to use the #debug command. However, that command does not display its messages in the POV-Ray Messages window. So use the #warning command instead, which functions the same as #debug, but directs its messages to the POV-Ray Messages window, where you can see them.

Chapter 11¶

Page 299¶

The code block in Exercise 11.26 erroneously uses the POV reserved word end as a variable. Another choice should have been made, such as stop:

  LinearPath(start,stop,rad)

Chapter 12¶

Page 336¶

In Exercise 12.29, the formula $b_{i,n}(t)$ should be written instead as $b_{n,i}(t)$ , to be consistent with the notation in later chapters.