SuperfieldCU
commented
2 years ago I decided to add an image comparison. I took a screenshot of the original game running in DosBox. DosBox screenshots are taken in their internal uncorrected resolution (320x200 in this case).
This first image was scaled up by 5 times, becoming 1600x1000 - each 1x1 pixel was blown up to 5x5. Therefore, it's exactly the same as the 320x200 image, just larger.
This second image is the same as the first, but while the width was increased by a factor of 5, same as above, the height was scaled by a factor of 6, resulting in a resolution of 1600x1200. This makes the 1x1 pixels become 6x5, giving the best possible depiction of the intended aspect ratio correction.
And here's a screenshot from rottexpr running in 1920x1080.
For a more direct comparison, I set the resolution in rottexpr to 320x240 and scaled it to 1600x1200.
Comparing the second and fourth images should give a very clear picture of what's wrong. It's not just the HUD elements and hand+pistol sprite; the blocks on the left are clearly too short and have short ovals instead of circles.
Rise of the Triad worked the same way as many DOS games of the era did: it had an internal rendering resolution of 320x200 (16:10 aspect ratio) which was then stretched vertically by 20% (making it a 4:3 image). This "corrected aspect ratio" mode was always how RotT was intended to be shown - the game has non-square pixels. However, it seems as though rottexpr does not do this vertical stretching in any way, resulting in the whole game appearing squashed.