Re: Image transformations

[Eli Zaretskii]

On June 25, 2019 6:28:32 AM GMT+03:00, Stefan Monnier <address@hidden> wrote:
> 
> >> Also, one of the two matrices can't be computed if the
> transformation
> >> turns the 2D image into a line (or a point).
> > We don't support such transformations.
> 
> There's no option to "magnify" by a factor 0?

Factor zero will give you zero pixels, which is not what you want.

But more generally: no, we don't currently support that.  Did you try it?

> >> Compared to the cost of handling the image, inverting a 3x3 matrix
> >> is probably negligible, tho.
> > Maybe so, but it still sounds silly to me.
> 
> Part of the reason for my question above is to figure out if the
> implementation of the API is likely to have such matrix inversion
> code internally

How can we possibly know for sure, on all supported platforms?

 > (since it seems quite possible that sometimes one is
> preferable and sometimes the other).

I admit I don't see why we would have different preferences.  We need to comply 
to public interfaces, which means use what they require.