Chapter 7

dp
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Posts: 4

Chapter 7 Oct 27, 2022 1:21:34 GMT

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Post by dp on Oct 27, 2022 1:21:34 GMT

Hi,

I am stuck at the end of chapter 7. The test "Constructing a ray when the camera is transformed" is failing because the result I get for the ray direction is: (- sqr2/2, 0, - sqr2/2) (note the x is negative)
All the other tests in that section are passing.

And when I render the scene at the end of chapter 7 I get an inversion and 2 scenes.
I checked my code but obviously I missed something

any help to see where I need to look closer ?

thanks.

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Last Edit: Oct 27, 2022 1:30:34 GMT by dp

dp New Member Posts: 4	Chapter 7 Nov 11, 2022 5:54:38 GMT Jamis likes this Quote Select Post Deselect Post Link to Post Member Give Gift Back to Top Post by dp on Nov 11, 2022 5:54:38 GMT I moved along continuing with the book but I finally found my issue. x and y swapped and bad memory allocation. (looks like I might have some issue with the cone though) Attachments:
	Last Edit: Nov 11, 2022 5:56:36 GMT by dp

paj006
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Posts: 1

Chapter 7 Mar 15, 2023 4:14:11 GMT

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Post by paj006 on Mar 15, 2023 4:14:11 GMT

I have the exact same issue. Where exactly were x, y switched? I have been trying to switch them in different places but then I get 'no index' errors.

EDIT it was in the 'toPPM' function. You have to loop height first, then columns.
This passes the chapter 2 test because the test 'image' is symmetrical - the pixel is in the exact center. Thus, looping column first gets the same result as looping row first. And to make things worse, the pixel in the middle uses a symmetrical RGB value!

SUGGESTION: Change the chapter 2 test so the green pixel is not in the exact middle.

Last Edit: Mar 15, 2023 5:16:50 GMT by paj006

Post by dp on Oct 27, 2022 1:21:34 GMT

Post by dp on Nov 11, 2022 5:54:38 GMT

Post by paj006 on Mar 15, 2023 4:14:11 GMT