A handful of bugs in the implementation of pbrt have been found since the book publication; we won't include the corresponding source code changes as errata in this list. Please refer to the commits to the "book" branch of the source code for details of and fixes for those errors.

If you find any errors in the book not listed on this page, please send a note to authors@pbrt.org.

## Important Errors

Page Reporter Error
160 Wei-Feng Huang In the bottom displayed equation, the 1/2 factor should apply to both terms; there should be parenthesis around them.
269 Kostya Smolenskiy In the second and third line of the third paragraph, replace "[128, 255]" with "[8, 15]" and replace "[128, 191]" with "[8, 11]".
388 Wei Tao In Equation (6.4), the expression inside the square root should be "(p_z - z_f - p'_z)(p_z - z_f - 4f - p'_z)".
809 Wei-Feng Huang, Antoine Büsch The third displayed equation should be "\tan^2 \theta' = -\alpha^2 \log (1 - \xi)". In turn, the following text ", though we must take care..." should be deleted and the source code should be updated accordingly.
892 Wei-Feng Huang In the equation at the top of the page, the upper limit of the integral should be t_max.
918 Steve Hill In the denominator in the displayed math, the "3/2" exponent should be outside the parenthesis.
972 Jinfeng Guo In the 5th line of the third paragraph, "r \rightarrow \infty" should be "r \rightarrow 0".

## Minor Errors

Page Reporter Error
xxvi Christophe Hery In the 10th line of the 4th paragraph, "Christiphe Hery" should be "Christophe Hery".
xxviii Hualin Xu In the 4th line of the 3rd paragraph, "were was" should be "were".
11 Hualin Xu In the 5th line of the 3rd paragraph, the full name of BSSRDF "bidirectional subsurface scattering reflectance distribution function" should be "bidirectional scattering surface reflectance distribution function" in order to correspond to the full name in Section 5.6.2.
33 Kostya Smolenskiy The parenthetical in the last line of the first paragraph, "(not included here)", should be deleted.
42 Kostya Smolenskiy In the 2nd line of the 1st paragraph, "previous" should be "new".
48 Mike Day In the 3rd line of the 4th paragraph, "continued to be use" should be "continued to use".
49 Per Christensen In the 2nd to last line of the 2nd to last paragraph, "deisgned" should be "designed".
51 Matt Pharr In the first line of the 3rd paragraph, "the Blue Sky studio" should be "Blue Sky Studios".
51 Antoine Büsch In the third line of the 3rd paragraph, "attenation" should be "attention".
51 Matt Pharr In the first line of the 7th paragraph, "RenderMan" should be in italics, to be consistent with other renderer names.
59 Per Christensen In the first line of the last paragraph, "vectors" should be "vector".
62 Kostya Smolenskiy The caption text for Figure 2.4(b) is unclear. A better phrasing would be: "If we consider the parallelogram formed by two vectors, the diagonals are given by w-v (dashed line) and -v-w (not shown)."
64 Kostya Smolenskiy In the 4th paragraph, "form a coordinate system" should be "form an orthogonal coordinate system".
69-70 Kostya Smolenskiy The second method in the last fragment in page 69 should be moved to the first fragment on page 70.
64 Mike Day In the right hand side of the second line of the first displayed equation, "v \cdot u" should probable be "u \cdot v".
65 Mike Day In Equation 2.2, the absolute value of \sin \theta should be used.
73 Mike Day In Equation 2.3, the first less-than sign should be a less-than or equal sign.
79 Mike Day In the very last line of the page,"by a constant factor in both dimensions" should be "by a constant amount in all dimensions".
82 Mike Day In the displayed math at the bottom of the page, a different symbol than an equals sign should be used (e.g. a left/right arrow), since this isn't strictly an equality.
82 Girish Ramesh In the first line of Section 2.7.1, the point p should be p_o.
82 Kostya Smolenskiy In the middle of the first paragraph of section 2.7.1, "four vectors" should be "four-vectors".
86 Tzu-Chieh Chang (張子捷) In the 3rd line of the first paragraph, $[x y z 1]$ should be $[x y z 1]^T$.
88 Kostya Smolenskiy In the 3rd line of the 4th paragraph, the words "normalized and" should be inserted before "orthogonal to each other".
88 Mike Day In the paragraph after the first displayed math, "upper 3x3 components" should be "first three columns (or rows)"
93 Tzu-Chieh Chang (張子捷) In the 2nd line of the 3rd paragraph, "row vector" should be "column vector".
97 Kostya Smolenskiy The start of the caption of Figure 2.15 would be more clear as "Three spheres, reflected in a mirror..."
97 Kostya Smolenskiy In the second paragraph of section 2.9, "181 degrees" should be "179 degrees".
98 Hualin Xu In the 2nd-3rd lines of the 5th paragraph, "concatentation" should be "concatenation".
101 Hualin Xu In the upper right element of the matrix in Equation (2.6), there should be an opening parenthesis after the 2.
102 Joey Litalien Two lines above Equation 2.7, "q_1 onto q_2" should be "q_2 onto q_1".
110 Hualin Xu In the 5th line of the first paragraph, "are are" should be "are".
114 Kostya Smolenskiy The displayed equation should be parenthesized such that c_3,x is multiplied by cos 2 \theta t and similarly for c_5,x, sin 2 \theta t.
116 Per Christensen In the first line of the second paragraph, "a" should be inserted before "particular".
117 Kostya Smolenskiy Because pbrt uses a left-handed coordiante system, in Figure 2.19, dp/du and dp/dv should be swapped so that the orientation of the normal from the cross product is correct.
119 Per Christensen In the 4th line of the second paragraph, "same" should be inserted before "hemisphere".
148 Per Christensen In the first line of the 4th paragraph, insert "and" before "checks".
153 Kostya Smolenskiy The very last displayed equation should be "F \approx 2V".
154 Kostya Smolenskiy In the very first line, "twice as many vertices as faces" should be "twice as many faces as vertices".
155 Kostya Smolenskiy In the second line of the third paragraph, insert ", and transforms the vectors to world space" after "values".
155 Hualin Xu In the 3rd line of the 3rd paragraph, "object" should be "world".
159 Wei Tao In the first displayed equation, "T" should be "P".
160 Kostya Smolenskiy In the second line of the second paragraph, insert "length of the" before "cross product".
161 Kostya Smolenskiy In the third line of the first paragraph, insert "twice" before "the area".
161 Tzu-Chieh Chang (張子捷) In the 2nd line after display equation (3.2), "p_i" should be "p_{(i + 1) \mod 3}" and "p_{(i + 1) \mod 3}" should be "p_{(i + 2) \mod 3}".
162 Yue Ren (任悦) The final displayed equation could be read to be suggesting that t_max is equal one of the two values on the right hand of the brace, while the intended meaning is actually that the inequality t < t_max can equivalently be expressed in those two ways.
162 Bojian Wu Either the implementation should use the variable "d" for the determinant, or the "d" in the 4th line of the 6th paragraph should be "det".
165 Antoine Büsch In the last line of the last paragraph, "consisting" should be "consistent".
166 Tzu-Chieh Chang (張子捷) In the third line of the first paragraph, "180" should be "90".
176 Per Christensen In the third line of the caption for Figure 3.21, "side of edge" should be "side of the edge".
177 Per Christensen In the first line of the caption for Figure 3.22, insert "this" before "part".
192 Matthias B. Hullin The section title is misspelled: it should be "Subdivision".
199 Hualin Xu The start of last sentence of the first paragraph should be: "For any odd vertex on the edge of a face, ..."
208 Kostya Smolenskiy Two lines above the displayed math, $e_b$ should be $e$.
210 Kostya Smolenskiy At the start of the 6th and 8th paragraphs, "With $e_b = 255$" should be "With $e = 255$".
214 Per Christensen In the 4th line of the caption for Figure 3.41, change "ticks in" to "ticks on".
223 Kostya Smolenskiy In equation 3.13, the plus/minus sign should just be a plus sign.
228 Kostya Smolenskiy Right before the first displayed equation, "transformed point" should be "transformed coordinate".
234 Yue Ren (任悦) In the second to last displayed equation on the page, \gamma_2 should be \gamma_1.
208 Kostya Smolenskiy In the second displayed equation in Exercise 3.1, "2Gz" should be "2Gx".
272 Kostya Smolenskiy In the last line of the first paragraph, "EncodeMorton3()" should be replaced with "LeftShift3()".
277 Kostya Smolenskiy The total number of nodes in a binary tree (e.g. a BVH) is bounded by twice the number of leaf nodes minus one. Thus, in the second line of code on the page, the initializer could be "2 * nPrimitives - 1".
277 Yue Ren(任悦) In the second line of the second paragraph, "LVBH" should be "LBVH".
315 Kostya Smolenskiy The third line of the second paragraph, "offset" should be "offer".
320 Kostya Smolenskiy The third line of the caption for Figure 5.2, "FromSampled()" should be "AverageSpectrumSamples()".
323 Jonathon Cai In the caption for Figure 5.3, the use of the word "convolved" in incorrect.
327 Neil You The first line of the first displayed equation suggests the equality S(lambda) = x_\lambda X(\lambda) + y_\lambda Y(\lambda) + z_\lambda Z(\lambda) for an arbitrary SPD S(\lambda), which is not the case. The text should make more clear that we're making use of the tristimulus theory of color perception in that step.
328 Jonathon Cai In the third paragraph, "ToRGB()" should be "ToRGBSpectrum()".
335 Jonathon Cai In the second to last line on the page, "means that" should be deleted.
345 Hualin Xu In the 1st line of the caption for Figure 5.15, "d_A" should be "d_omega".
356 Jonathon Cai In the first line of the fifth paragraph, "an pointer" should be "a pointer".
357 Jonathon Cai In the 4th line of the 3rd paragraph, "to set" should be "set".
363 Kostya Smolenskiy In Figure 6.4, (0,0) should be at the upper left, and (xRes, yRes) at the lower right.
365 Per Christensen In the last line of the last paragraph, delete "a" before "ray tracers".
368 Kostya Smolenskiy In the first two lines of the 4th paragraph, "parallel incident rays...behind the lens" should be rewritten as "incident rays that are parallel to the optical axis and pass through the lens focus at a point behind the lens". (A similar fix should be made in the caption of Figure 6.6.)
369 Per Christensen In the second line of the last paragraph, change "This boundary" to "The boundary".
372 Kostya Smolenskiy In Figure 6.11(a), the point z should be to the right of z_f in order for the point z' to be behind z'_f.
372 Kostya Smolenskiy In the 5th line of the caption for Figure 6.11, there should be a comma after d_c.
379 Hualin Xu In the 3rd line of the 4th paragraph, "As in Section 6.2.3," should be deleted. Then, the following "lens" should be capitalized.
391 Jonathon Cai In the caption for Figure 6.23, $-\theta$ should be $\theta$.
396 Hualin Xu In the 4th line of the 2nd paragraph, "times" should be "divided by".
397 Per Christensen In the first line of the last paragraph, insert "of" after "implementation".
398 Hualin Xu In the 3rd line of the 1st paragraph, "2006" should be "2007".
420 Per Christensen In the 4th line of the 4th paragraph, insert "the" before "volume".
441 (and beyond) Per Christensen We should distinguish between point sets (of fixed size), like Hammersley, and point sequences (of potentially infinite size), like Halton.
447 Zejian Wang In the 3rd line of the last paragraph, "value" should be "reversedDigits".
450 Per Christensen In the third line of the last paragraph, change "can be lead to" to "can lead to".
457 Wei-Feng Huang In Equation 7.9, "b^n" should be "b^{-n}".
458 Per Christensen In the second line of the first paragraph, delete "now".
459 Per Christensen In the 5th line of the second paragraph, insert "until" before "all".
460 Per Christensen In the third line of the caption for Table 7.4, delete "with".
461 Christian Hipp In the first line of the third paragraph, "the" should be inserted beforoe "heart".
477 Pavel Krajcevski Contrary to what's written in the third paragraph, the triangle filter as implemented doesn't have a weight of 1 at its center.
509 Jonathon Cai Figure 8.1(c) should probably be updated to make it more clear that with perfect specular reflection, there is only a single reflected direction.
518 Kostya Smolenskiy In the last line of the 4th paragraph, "\cos_t" should be "\cos \theta_t".
530 Per Christensen In the second line of the last paragraph, "was" should be "as".
533 Per Christensen There aren't any names for the parameters to the rho() methods in the second code fragment. (Inconsistent with the rest of the book).
545 Jeppe Frisvad In Figure 8.20, \theta and \theta_h should be swapped (for consistency with their usage elsewhere).
545-548 Jeppe Frisvad Thoughout Section 8.4.4, \theta_h should be replaced with \theta (for consistency with earlier usage of \theta_h as the angle between \omega_h and the surface normal.)
546 Andreas Wendleder Writing the Fresnel term as F_r(w_o) makes it unclear that its value also dependends on w_h.
552 Jinfeng Guo In the last two lines of the third paragraph, "scenes/brdfs directory in the pbrt distribution" should be "brdfs directory in the pbrt scenes distribution".
554 Per Christensen In the third line of the second paragraph, a comma should be inserted after the closing parenthesis.
561 曹家音 In the third line of Equation (8.29), the last term on the right hand side should be "-w_0".
563 Per Christensen In the first line of the third paragraph, "the" before w_3 should be deleted.
582 Kostya Smolenskiy In the first line of the second paragraph, "b1" should be "m1".
624 Per Christensen In the 7th line of the last paragraph, "the triangle filter" should be "trilinear interpolation".
655 Srinath Ravichandiran In the last line of text on the page above the displayed math, "f_s(s)" should be "f_s(x)".
672 Per Christensen In lines 2-3 of the last paragraph, delete "given spatial extent".
709 Per Christensen In the third line of the first paragraph, "overall" should be "over all".
713 Per Christensen In the second line of the caption for Figure 12.3, delete "in".
715 Per Christensen In the second line of the second paragraph, change "so that it's", to ", so it's".
724 Per Christensen In the last line of the second paragraph, replace "width" with "falloffWidth", and "fall" with "falloffStart". (Match earlier notation, e.g. in Figure 12.8.)
741 Antoine Büsch In the 4th line of the second paragraph, "values" should be "varies".
743 Per Christensen In the third line of the second paragraph, insert "from" after "illumination".
754 Antoine Büsch In the last line of the caption for Figure 13.2, the "p_i" in the sum should be "p_j".
760 Per Christensen Delete "in" at the end of the fourth line of the second paragraph.
778 Per Christensen In the last line of text, "two wedges" should be "seven wedges".
780 Per Christensen In the second line of the caption for Figure 13.14, "sphere" should be "hemispehre".
788 Jonathan Klein In the displayed math at the bottom of the page, "dw" should be the first differential term after the integrand. Also, "dx dy" should be "dA".
801 Per Christensen In the last line of Exercise 13.2, O(\sqrt{n}) should be O(n).
806 Jonathan Klein In the third line of the second to last paragraph, there should be a period after "coordinate system".
812 Jeppe Frisvad In Figure 14.4, \theta_h should be \theta.
813 Jeppe Frisvad In the numerator of the right hand side of the last displayed equation on the page, \theta should be \theta_h.
823 Matt Pharr In the first line of the third code fragment, there are two spaces after the comma.
828 Matt Pharr In the first line of the third paragraph, there should be a comma after "(8.22)".
828 Zejian Wang In the summation in Equation 14.9, there should be a factor of a_k.
829 Per Christensen In the second line of the first paragraph, "sample in the each" should be "sample in each".
845 Per Christensen In the second line of the third paragraph, "value it returns from" should be "value it returns".
851 Per Christensen In the second line of the first paragraph, "only accounts for only" should be "only accounts for".
875 Wenzel Jakob In the first displayed equation, p_A should be p_A(p_i), the denominator should be p_{i+1}-p{i} (for consistency with the earlier definition), and similarly, the following line should read "...terms of the geometric term G(p_{i+1} <-> p_{i})".
884 Christian Hipp In the second line of exercise 14.9 "performs" should be "perform".
905 Zejian Wang In the 5th paragraph, an opening parenthesis is missing before "1 - F_t(\cos \theta))". (More generally, it might make sense to remove the closing parenthesis and then both opening and closing parenthesis in the earlier expression of the same form.)
906 Christian Hipp In line 6 of the 3rd paragraph, "much a simpler" should be "a much simpler".
907 Per Christensen In the first line of the last paragraph, "a different a sampling" should be "a different sampling".
913 Christian Hipp In line 5 of the 2nd paragraph in Section 15.4.2, "for to the given" should be "for the given".
919 Steve Hill The light distribution plots shown actually correspond to 5, 10, and 100 scattering events, respectively.
905 Zejian Wang In Equation 15.47, the last \cos \theta_o term should be its absolute value.
938 Per Christensen In the third line of the 6th paragraph, the second sigma_s should be sigma_a. Further, it might be more clear to rewrite to just multiply by sigma_t rather than dividing by sigma_t^{-1}.
944 Per Christensen In the second line of Exercise 15.4, "this more effective" should be "this is more effective".
944 Christian Hipp In line 4 of exercise 15.5, "often be sampled" should be "more often be sampled".
947 Christian Hipp In the 6th line of the 2nd paragraph, "photons have" should be "photons that have".
949 Per Christensen In the first and second lines of the last paragraph, "value of importance function" should be "value of the importance function".
951 Christian Hipp In the first line of the first paragraph, "a ideal sensor" should be "an ideal sensor".
961 熊伟 In the 4th line of the first paragraph "below" should be "above".
964 Per Christensen In the art for Figure 16.5, the alphas should be betas.
969 Jinfeng Guo In the text right before Equation (16.11), "\omega" should be "\omega_o".
979 Jinfeng Guo In the second line of the first paragraph, "path" should be "pass".
971 Per Christensen In the third line of the second to last paragraph, "photons that are found" should be "photons are found".
972 Per Christensen In the 5th line of the third paragraph, the limit for r should be "r \rightarrow 0".
988 Per Christensen In the second line of the third paragraph, insert "a" before "distribution of photons".
991 Jinfeng Guo, Wei-Feng Huang In the second line after the displayed math at the middle of the page, q_{s'} should be q_{s'-1} and p_{t'} should be p_{t'-1}.
1005 Wei-Feng Huang In fourth line of the second paragraph, "pdfFwd" should be "pdf".
1008 Christian Hipp In the 2nd line of the first paragraph, "soid" should be "solid"
1011 Wei-Feng Huang In fifth line of the first paragraph, T(\bar{p}_t) should have a \hat{} over the T.
1011 Wei-Feng Huang In second line after the second displayed equation "camera path" and "light path" should be exchanged.
1020 Christian Hipp In the 2nd line of the 5th paragraph, "a infinite" should be "an infinite".
1031 Wei-Feng Huang In the first line of the first paragraph, "MLTIntegrator" should be "MLTSampler".
1044 Per Christensen A better reference for Lafortune and Willems (1994) would be "Lafortune, E. and Y. Willems, Bi-directional path tracing. 1993. Proceedings of Compugraphics 1993. 145--53."
829 Per Christensen In the last line of the page, "contaminated surfaces" should be "surfaces covered".
1052 Jim Price In the second line of the first bullet at the bottom of the page, "word" should be "world".
1053 Jim Price In the first sentence of section 17.1.2, the word "of" is repeated twice in a row.
1058 Per Christensen In paragraph four, Christensen et al (2006) "Ray tracing for the movie Cars" should be cited for the idea of testing a ray against four bounding boxes using SSE instructions.
1068 Jonathon Cai In the third line on the page, "totalResolution" should be "(totalResolution.x, totalResolution.y)".
1074 Christian Hipp In the 2nd line of the footnote, "substantially times slower" should be "substantially slower".
1084 Per Christensen In the very last line of the page, "newMax" should be "localMax".
1085 Kostya Smolenskiy In the third line of text, "vaxValue" should be "maxValue".
1085 Christian Hipp In the last line of the last paragraph, "not necessarily not equal" should be "not necessarily equal".
1170 Matt Pharr A closing parenthesis should be added after "Proceedings" in the Christensen et al. 2003 citation.
1203 Hualin Xu For the Stephenson reference, "2006" should be "2007".
1208 Matt Pharr The Whitted citation is not in the correct alphabetical order.
1223 Jeremy Cowles The index should have an entry for "Nyquist frequency", which is defined on page 410.