Re: [hatari-devel] Pixel aspekt ratio

[David Savinkoff <dsavnkff@xxxxxxxxx>]

----- Troed Sångberg wrote:
> Recently I realized that graphics I made on my Mac and displayed in Hatari
> did not look the same as when I viewed it on my ST. On the ST everything
> was stretched out vertically.
> 
> I couldn't really understand why, so I started looking for discussions on
> Atari ST pixel sizes, and found the following:
> 
> "and later on the 16-bit Atari ST (low-resolution 320×200 pixels) each
> pixel was roughly .9×1"
> 
> https://mmolyneaux.wordpress.com/category/atari-st/
> 
> Going by the above I stretched the graphics by a factor 1.11 horizontally
> and all of a sudden a photo taken from the graphics as displayed on the ST
> matched perfectly what was displayed in Hatari.
> 
> Is this a general thing with modern monitors having square pixels so that
> an emulator with 1:1 mapping will always display things "compress"
> vertically compared to what was originally designed for target?
> 
> If so, should Hatari offer the option to not do 1:1 mapping but stretch
> vertically to try to display content as close to what it would look like
> natively?
> 
> Sorry if this is a topic that has been debated to death before, it was new
> to me when I stumbled upon it.
> 
> /Troed

Hi,

I gave a quick look at .png picture information any they mention
aspect ratio.
One would expect a picture format should display with the correct
aspect ratio.
Thus, Hatari should be able to produce a picture with any dimension,
and any aspect ratio by simply providing the correct header for .png.

As for a display window, the scaling should be 'offloaded' to the
operating system by simply providing the information, and not with
an assumed 1:1 aspect ratio.

Will SDL2 allow the user to stretch the window by dragging the edge?
(This can be done in OpenGL without fiddling with pixels)