Re: comments on Matrix

Sent from my iPhone

On Mar 21, 2013, at 11:39 AM, "Tab Atkins Jr." <jackalmage@gmail.com> wrote:

> On Thu, Mar 21, 2013 at 11:33 AM, Rik Cabanier <cabanier@gmail.com> wrote:
>> SVG matrix throws an exception and since this is a drop-in replacement,
>> Matrix needs to throw one too :-(
> 
> Are we sure about that?  I'd prefer to look at some SVGMatrix-using
> code to see if it actually relies on singular matrixes throwing, or if
> it just assumes they never will (my assumption) or simply ignores
> failure.  If either of the latter, we should feel free to change
> behavior.
> 
>> Most libraries seem to return a boolean to say that a inversion failed which
>> seems better. I *believe* adding an exception to JS also forces the creation
>> of an exception object every time which is expensive.
> 
> Only if you actually throw it.  It's not eagerly created every call.
> 
>> Why don't we add another Inverse:
>> 
>> boolean Inverse(Matrix);
>> 
>> We could also move to unrestricted doubles so we can populate the matrix
>> with NaN or Inf if needed.
> 
> Yes, that seems fine.


That sounds weird. Users would actually never be able to rely on the matrix values and would need a sanity check of the matrix the whole time. Note that this is not at all the case for current implementations nor graphic libraries.

Dirk

> 
> ~TJ
>