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

abtin
page 20: … protoc command… I had to additionally run the following go get commands in order to be able to compile protobuf code using go...
New
jimschubert
In Chapter 3, the source for index introduces Config on page 31, followed by more code including tests; Config isn’t introduced until pag...
New
jon
Some minor things in the paper edition that says “3 2020” on the title page verso, not mentioned in the book’s errata online: p. 186 But...
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
hgkjshegfskef
The test is as follows: Scenario: Intersecting a scaled sphere with a ray Given r ← ray(point(0, 0, -5), vector(0, 0, 1)) And s ← sphere...
New
brunogirin
When running tox for the first time, I got the following error: ERROR: InterpreterNotFound: python3.10 I realised that I was running ...
New
mert
AWDWR 7, page 152, page 153: Hello everyone, I’m a little bit lost on the hotwire part. I didn’t fully understand it. On page 152 @rub...
New
Keton
When running the program in chapter 8, “Implementing Combat”, the printout Health before attack was never printed so I assumed something ...
New
a.zampa
@mfazio23 I’m following the indications of the book and arriver ad chapter 10, but the app cannot be compiled due to an error in the Bas...
New
redconfetti
Docker-Machine became part of the Docker Toolbox, which was deprecated in 2020, long after Docker Desktop supported Docker Engine nativel...
New

Other popular topics Top

Devtalk
Hello Devtalk World! Please let us know a little about who you are and where you’re from :nerd_face:
New
Exadra37
I am thinking in building or buy a desktop computer for programing, both professionally and on my free time, and my choice of OS is Linux...
New
siddhant3030
I’m thinking of buying a monitor that I can rotate to use as a vertical monitor? Also, I want to know if someone is using it for program...
New
brentjanderson
Bought the Moonlander mechanical keyboard. Cherry Brown MX switches. Arms and wrists have been hurting enough that it’s time I did someth...
New
PragmaticBookshelf
Tailwind CSS is an exciting new CSS framework that allows you to design your site by composing simple utility classes to create complex e...
New
AstonJ
In case anyone else is wondering why Ruby 3 doesn’t show when you do asdf list-all ruby :man_facepalming: do this first: asdf plugin-upd...
New
PragmaticBookshelf
Use WebRTC to build web applications that stream media and data in real time directly from one user to another, all in the browser. ...
New
foxtrottwist
A few weeks ago I started using Warp a terminal written in rust. Though in it’s current state of development there are a few caveats (tab...
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

Sub Categories: