POV-Ray : Newsgroups : povray.binaries.animations : Absolutely relative woes : Re: Absolutely relative woes Server Time
23 Apr 2024 23:33:28 EDT (-0400)
  Re: Absolutely relative woes  
From: Dick Balaska
Date: 24 Feb 2020 17:05:07
Message: <5e544893$1@news.povray.org>
Am 2/23/20 10:16 PM, also sprach Bald Eagle:
> Dick Balaska <dic### [at] buckosoftcom> wrote:
> 
>> I don't know what I'm doing wrong.
> 
> I can't really see it either, but maybe just do a simple scene with spheres 
> ...
> and see if anything jumps out.
> 

Ugh.  What jumps out is ... I told a half truth.  When I perform the 
calcs in actual SDL it works as expected.  When I do it in my c++ 
library, that I ported from my Java library, that I ripped from the 
POV-Ray source (core/math/matrix.cpp), that I've used for years, I get 
the wrong answer.

Comparing the logic flow of my
void Vector::rotateDegrees(const Vector& rot){}
with POV-Ray's
void Compute_Rotation_Transform (TRANSFORM *transform, const Vector3d& 
vector)

I see a matrix multiplication difference (there are two different 
multiplies and I used one).

I can't believe I never saw this before.

-- 
dik
Rendered 49,882,521,600 of 49,882,521,600 pixels (100%)


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