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

yulkin
your book suggests to use Image.toByteData() to convert image to bytes, however I get the following error: "the getter ‘toByteData’ isn’t...
New
lirux
Hi Jamis, I think there’s an issue with a test on chapter 6. I own the ebook, version P1.0 Feb. 2019. This test doesn’t pass for me: ...
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
raul
Page 28: It implements io.ReaderAt on the store type. Sorry if it’s a dumb question but was the io.ReaderAt supposed to be io.ReadAt? ...
New
jskubick
I’m running Android Studio “Arctic Fox” 2020.3.1 Patch 2, and I’m embarrassed to admit that I only made it to page 8 before running into ...
New
adamwoolhether
I’m not quite sure what’s going on here, but I’m unable to have to containers successfully complete the Readiness/Liveness checks. I’m im...
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
dsmith42
Hey there, I’m enjoying this book and have learned a few things alredayd. However, in Chapter 4 I believe we are meant to see the “>...
New
jonmac
The allprojects block listed on page 245 produces the following error when syncing gradle: “org.gradle.api.GradleScriptException: A prob...
New
gorkaio
root_layout: {PentoWeb.LayoutView, :root}, This results in the following following error: no “root” html template defined for PentoWeb...
New

Other popular topics Top

AstonJ
What chair do you have while working… and why? Is there a ‘best’ type of chair or working position for developers?
New
DevotionGeo
I know that these benchmarks might not be the exact picture of real-world scenario, but still I expect a Rust web framework performing a ...
New
AstonJ
Curious to know which languages and frameworks you’re all thinking about learning next :upside_down_face: Perhaps if there’s enough peop...
New
PragmaticBookshelf
Rust is an exciting new programming language combining the power of C with memory safety, fearless concurrency, and productivity boosters...
New
AstonJ
I ended up cancelling my Moonlander order as I think it’s just going to be a bit too bulky for me. I think the Planck and the Preonic (o...
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
AstonJ
Was just curious to see if any were around, found this one: I got 51/100: Not sure if it was meant to buy I am sure at times the b...
New
New
New
AstonJ
This is a very quick guide, you just need to: Download LM Studio: https://lmstudio.ai/ Click on search Type DeepSeek, then select the o...
New

Sub Categories: