jdunlap

jdunlap

The Ray Tracer Challenge: Implementing Shading Breaks the First Shading Test on P. 95

I am working on Chapter 8 when we add shadows. When this is done, though (on p. 115), the original ShadeHit test no longer passes. This point is in shadow and will, therefore, break the tests once shading is implemented.

My solution was to add a flag to turn shading on and off. It defaults to on, but I turn it off before running this test so that it runs as originally intended. I then turn it back on for the final test that is added on p. 114.

For anyone who wants to just update the test, here is the value that I get:

Expected: {0.38066, 0.47583, 0.2855, 0 }
Actual: {0.08, 0.1, 0.06, 0 }

The Actual would just be the ambient color of the sphere.

The second test from p. 95 also fails. Those values are:

Expected: {0.90498, 0.90498, 0.90498, 0 }
Actual: {0.1, 0.1, 0.1, 0 }

Edit:

Shading also breaks the Render test on p. 104 and the second colorAt test on p. 96.

These tests need to be changed to test for the Ambient color or shading needs to be turned off to run them.

It would be nice if Jamis would create tests for all of these that are not in shade or would adjust these tests in the text since the design of the program changed.

First Post!

jamis

jamis

Author of Mazes for Programmers and 1 other title

Hello,

The tests as written should be passing; my own renderer passes all tests, through the end of the book. Admittedly, there could very well be an error in my own code that permits this, but other readers have also had these tests pass after the shadow chapter.

Is your code hosted anywhere that I can see it? I’d be happy to take a look.

  • Jamis

Where Next?

Popular Pragmatic Bookshelf topics Top

ianwillie
Hello Brian, I have some problems with running the code in your book. I like the style of the book very much and I have learnt a lot as...
New
Alexandr
Hi everyone! There is an error on the page 71 in the book “Programming machine learning from coding to depp learning” P. Perrotta. You c...
New
JohnS
I can’t setup the Rails source code. This happens in a working directory containing multiple (postgres) Rails apps. With: ruby-3.0.0 s...
New
leonW
I ran this command after installing the sample application: $ cards add do something --owner Brian And got a file not found error: Fil...
New
oaklandgit
Hi, I completed chapter 6 but am getting the following error when running: thread 'main' panicked at 'Failed to load texture: IoError(O...
New
hazardco
On page 78 the following code appears: <%= link_to ‘Destroy’, product, class: ‘hover:underline’, method: :delete, data: { confirm...
New
jonmac
The allprojects block listed on page 245 produces the following error when syncing gradle: “org.gradle.api.GradleScriptException: A prob...
New
tkhobbes
After some hassle, I was able to finally run bin/setup, now I have started the rails server but I get this error message right when I vis...
New
ggerico
I got this error when executing the plot files on macOS Ventura 13.0.1 with Python 3.10.8 and matplotlib 3.6.1: programming_ML/code/03_...
New
mcpierce
@mfazio23 I’ve applied the changes from Chapter 5 of the book and everything builds correctly and runs. But, when I try to start a game,...
New

Other popular topics Top

PragmaticBookshelf
Machine learning can be intimidating, with its reliance on math and algorithms that most programmers don't encounter in their regular wor...
New
PragmaticBookshelf
Free and open source software is the default choice for the technologies that run our world, and it’s built and maintained by people like...
New
Exadra37
Please tell us what is your preferred monitor setup for programming(not gaming) and why you have chosen it. Does your monitor have eye p...
New
AstonJ
There’s a whole world of custom keycaps out there that I didn’t know existed! Check out all of our Keycaps threads here: https://forum....
New
dimitarvp
Small essay with thoughts on macOS vs. Linux: I know @Exadra37 is just waiting around the corner to scream at me “I TOLD YOU SO!!!” but I...
New
Maartz
Hi folks, I don’t know if I saw this here but, here’s a new programming language, called Roc Reminds me a bit of Elm and thus Haskell. ...
New
AstonJ
We’ve talked about his book briefly here but it is quickly becoming obsolete - so he’s decided to create a series of 7 podcasts, the firs...
New
PragmaticBookshelf
Rails 7 completely redefines what it means to produce fantastic user experiences and provides a way to achieve all the benefits of single...
New
AstonJ
If you’re getting errors like this: psql: error: connection to server on socket “/tmp/.s.PGSQL.5432” failed: No such file or directory ...
New
PragmaticBookshelf
Get the comprehensive, insider information you need for Rails 8 with the new edition of this award-winning classic. Sam Ruby @rubys ...
New

Sub Categories: