Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle)

Subject	Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle)
Newsgroups	comp.lang.c++
References	<cYwKF.3051$vj3.487@fx10.dcg> <qteda4$1vi2$1@gioia.aioe.org>
From	Mr Flibble <flibbleREMOVETHISBIT@i42.co.uk>
Organization	Jupiter Mining Corporation
Message-ID	<9EEKF.6570$RQ.608@fx09.dcg> (permalink)
Date	2019-12-19 06:19 +0000

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On 18/12/2019 23:38, Chris M. Thomasson wrote:
> On 12/18/2019 1:34 PM, Mr Flibble wrote:
>> Hi!
>>
>> The following is the base class of my vector class (the mathematical vector not the container) so I can do things like:
>>
>> vec3 v1 = { 1.0, 2.0, 3.0 };
>> vec2 v2 = v1.xy;
>> double z = v1.z;
>> vec4 v3 = v1.xyzz;
>>
>> So we have an anonymous union of an anonymous struct and some swizzles and I suspect it is full of UB but I am finding it hard to care as I cannot see any other way of doing this.
>>
>> Collective thoughts/wisdom?
> [...]
> 
> Are you trying to get close to GLSL? The glm lib for C++ is very close, but its does not have the .xyz type of functionality. Interesting.
> 
> vec4 v4 = vec4(v3.xyz, 1.0);
> 
> v4 now equals { v3.x, v3.y, v3.z, 1.0 }

That is the goal, yes.

/Flibble

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Thread

Probably UB but I am finding it hard to give a fuck (C++ swizzle) Mr Flibble <flibbleREMOVETHISBIT@i42.co.uk> - 2019-12-18 21:34 +0000
  Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) Öö Tiib <ootiib@hot.ee> - 2019-12-18 14:24 -0800
    Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) Mr Flibble <flibbleREMOVETHISBIT@i42.co.uk> - 2019-12-18 23:14 +0000
      Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) Öö Tiib <ootiib@hot.ee> - 2019-12-18 15:36 -0800
        Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) Mr Flibble <flibbleREMOVETHISBIT@i42.co.uk> - 2019-12-19 06:18 +0000
      Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2019-12-19 10:49 +0100
      Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) Manfred <noname@add.invalid> - 2019-12-19 14:29 +0100
  Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-12-18 15:38 -0800
    Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) Mr Flibble <flibbleREMOVETHISBIT@i42.co.uk> - 2019-12-19 06:19 +0000
      Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-12-23 10:34 -0800
      Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-12-28 00:30 -0800
        Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) Mr Flibble <flibble@i42.removethisbit.co.uk> - 2019-12-28 15:53 +0000
          Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-01-31 23:00 -0800
  Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) Manfred <noname@add.invalid> - 2019-12-19 14:25 +0100
  Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) woodbrian77@gmail.com - 2019-12-20 08:22 -0800
    Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) Mr Flibble <flibbleREMOVETHISBIT@i42.co.uk> - 2019-12-21 13:23 +0000
  Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-01-11 15:08 -0800
    Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) Bonita Montero <Bonita.Montero@gmail.com> - 2020-02-10 18:35 +0100
      Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-02-10 14:07 -0800
  Re: Probably UB but I am finding it hard to give a fuck (C++ swizzle) "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-01-31 21:42 -0800

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