af Photo NOT precise

[firstdefence]

I used the image Thomahawk posted and it replicates exactly. I just drew a rectangular selection around the "one" and copy/pasted it, it is immaterial where it's placed the look is still the same.

Maybe a workflow on how the op achieved this poor result might help. 

[R C-R]

48 minutes ago, firstdefence said:

Maybe a workflow on how the op achieved this poor result might help. 

Without knowing the pixel dimensions of the canvas, what other layers this might be combined with & how, the intended end use(s), & so on, its all guesswork. 

[MikeW]

1 hour ago, firstdefence said:

I used the image Thomahawk posted and it replicates exactly. I just drew a rectangular selection around the "one" and copy/pasted it, it is immaterial where it's placed the look is still the same.

Maybe a workflow on how the op achieved this poor result might help. 

It's not an exact copy.

But yes, an original file, the actual image brought into APhoto would be good.

[R C-R]

8 minutes ago, MikeW said:

It's not an exact copy.

How so? When I open the png file @firstdefence included in his post in a new window & zoom in on the pair of ones in the Safari browser the copy looks like this:

As far as I can tell from that, they both have the same 5 x 12 px dimensions, the same vertical alignment, & the same greys. What do you see that is different?

[Thomahawk]

On 10/25/2019 at 12:23 AM, Medical Officer Bones said:

PS if you are looking for a reason for this behaviour in Photo: I believe all Affinity products use the same "viewport rendering" engine under the hood, and in applications such as Designer and Publisher decimal pixels make a lot of sense, because vector applications do not work with pixels. But Photo forces the viewport to be rendered into the pixel resolution we choose when the document is created, and MUST convert bitmap images placed at decimal positional values to that "native" resolution somehow. Which means an interpolated version of the original bitmap is generated in the view. Unless the Force Pixel Alignment option is turned on before working with bitmaps objects. This behaviour is confusing to Photoshop users (and not only Photoshop users).

 

Bones, I see what you mean. In my example, there is no need to recalculate anything. Recalculation  has to be done only, if you resize something or rotate in angles outside 90°. Otherwise, each pixel is just moved to the spot of another pixel. No antialias or any kind of change occurs.

Of course if you try to move a pixel only a half-pixel step, this would need recalculation, what I suppose is happening here. But I do not see any setting how to prevent this. In a pixel app, usual behaviour would be only to work in full pixel-steps (= nondestructive).

[Thomahawk]

Okay, I think I found the necessary setting. These two have to be activated. Without it, copy/moving the single pixel (left side) ends up like the two 2x2 block right to it. Only after activating these options, pixel stays how it originally was (copy on right side). This should be the standard setting for work in af Photo or else any movement is destructive.

 

[R C-R]

44 minutes ago, Thomahawk said:

Okay, I think I found the necessary setting. These two have to be activated.

As has already been discussed in great detail, in general for things like this you should enable "Force Pixel Alignment" (the left button) but not "Move By Whole Pixels (the right button) because the latter will move objects that currently are not aligned on whole pixel boundaries by whole pixel values. IOW, if something is currently at an x value of 10.5 px, with MBWP enabled a will move to 11.5, 9.5, etc. values, preserving the fractional pixel part of the x value.

This is not an issue if you start with both options enabled before creating anything in a new document, this won't be an issue bur for existing documents you should be aware of the difference.

44 minutes ago, Thomahawk said:

This should be the standard setting for work in af Photo or else any movement is destructive.

It is not destructive unless you rasterize the layer, but as for it being a standard setting these buttons are "sticky" (as are all the snapping options) meaning that once set they won't change if you open another existing or new document.