Transform selection seems to add pixels with unexpected colours

[Noel da Costa]

So picture this.... you have a square you have drawn and you fill it all with a flat blue fill. Now you rasterize that layer. Next you take the box selection tool and you draw a small selection within the blue box. Now you transform that selection on the x-axis only (i.e. horizontally). My expectation would be that however large you make the transform, all the pixels within should be blue – because there are no source pixels of any other colour.

However, that is not the behaviour demonstrated. Instead it seems to add white pixels to the start and end of the transform and the blue bit seems to get stretched out and fades into these white bits.

Now on GIMP you can control this behaviour by selecting "None" in the "Interpolation" drop-down option for the transform tool. There doesn't seem to be a way to control the interpolation in Affinity. I've attached an image where you can see the effect. Look inside the red circled area and you will notice that non-blue pixels have been introduced in the transformed selection. 

[MEB]

Hi Noel da Costa,
Welcome to Affinity Forums
This is a known issue that's already logged to be looked at. Happens the same with the desktop versions as well.