Dragging image into document positions it at fractional X/Y coordinates despite force pixel alignment and snapping

[patrick_h_lauke]

If I have an image open, with force pixel alignment and snapping enabled, and I drag another image onto it...that second image is more often than not positioned with a fractional (not pixel aligned) X/Y coordinate.

video demonstration - note how the image I drag in has a fractional X value

Affinity Photo 1.10.5.1342 / Windows 

 

similar/related to this other topic (which is still a problem)

 

[Alfred]

Do you have ‘Move by whole pixels’ disabled? Do the source and destination documents have the same document DPI?

[Old Bruce]

As Alfred asked turn off the middle one.

[patrick_h_lauke]

i have "Move by whole pixels" enabled. Disabling it doesn't change the behaviour here either. Yes, both images have the same DPI

[walt.farrell]

I see the same behavior for drag/drop from an external source such as File Explorer. The initial drop isn't pixel-aligned. Any movement using the Move Tool after that aligns it, though as long as Move by Whole Pixels is off. (One generally should have that option off, in my opinion, except for special occasions.)

One additional oddity, though: After dropping, and having it end up not aligned to the pixel grid, if I move it using the arrow keys, it does not snap to the grid. I must move it using the mouse.

[Old Bruce]

I wonder what else is turned on in for Snapping. When I want pixel aligned work I turn off anything related to Mid points and Margins and guides as these can easily be at fractional locations. Then there is snapping to other objects, they may not be at whole pixel locations. 

In essence if pixel alignment is important then enable Force Pixel Alignment and turn everything else off.

A note on Placing a file, the file may be 1200 x 900 pixels in size and when you place it by dragging to size you have it at 481 pixels wide and you will then have a fractional pixel difference in height.

[patrick_h_lauke]

Quote

I wonder what else is turned on in for Snapping

See screenshot above. I've turned off all midpoint etc stuff. Only snapping to grid (which is set to 8x8 with 8 subdivisions, for arcade/console game tile work), snap to guides, visible objects and their bounding boxes.

Quote

if pixel alignment is important then enable Force Pixel Alignment and turn everything else off

makes no difference in this scenario, I tried it. still results in fractional coordinates (same in the copy/paste scenario of the other thread).

 

[Old Bruce]

52 minutes ago, patrick_h_lauke said:

See screenshot above

You still have Move by Whole Pixels checked. And if your grid is set to something other than whole pixels then this won't work. Not to mention that Only Snap to Visible Objects might result in no snapping if you are not starting near a visible object.

Play around with having only Force Pixel alignment set. All else off.

 

[patrick_h_lauke]

as said, my grid is set to be pixel accurate as well (8x8 with 8 subdivisions)

and no, even *just* having "Force pixel alignment" on and nothing else, dragging an image over still results in fractional coordinates (but yes, after that moving them snaps them back to the pixel grid, but i'd really expect it to do that already without having to nudge it first)

 

[NotMyFault]

Placing an file is not related to move tool. You can place a file unrelated to any tool. The snapping settings are unfortunately related to specific tools, not global. So i agree that the observed behavior is unfortunate and should be changed asap, but unsure if you can argue it is a bug.

[patrick_h_lauke]

however, the snapping etc settings aren't shown as being just settings for the move tool. they appear in the top toolbar (not the context toolbar for the specific tool that's currently used). saying they're just specific to the move tool seems a bit odd...they're more along the lines of application-wide properties/settings

[NotMyFault]

Just now, patrick_h_lauke said:

however, the snapping etc settings aren't shown as being just settings for the move tool. they appear in the top toolbar (not the context toolbar for the specific tool that's currently used). saying they're just specific to the move tool seems a bit odd...they're more along the lines of application-wide properties/settings

Yes, it is far from clear to which operations snapping gets considered or not.

• Move tool, crop tool, creating vector shapes get impacted by snapping
• Pen and node tool has special snapping options for nodes and handles
• unsure about selection tools

[patrick_h_lauke]

from the help/documentation

Quote

Snapping simplifies the positioning of crop areas, selection areas, and layer content (pixel or vector)  ... 

 

[NotMyFault]

1 hour ago, patrick_h_lauke said:

from the help/documentation

 

Good find. It does not explicitly mention placing of layers, so it is up to Affinity to clarify.

[Dan C]

Hi @patrick_h_lauke,

Thanks for your report!

I can confirm that when using File > Place, these snapping options are respected - however when dragging and dropping the file from an external source (such as Explorer/Finder) I'm able to replicate the issue reported here.

I believe that these should be respected when dragging and dropping, so I'm logging this as a bug with our developers now.

19 hours ago, walt.farrell said:

One additional oddity, though: After dropping, and having it end up not aligned to the pixel grid, if I move it using the arrow keys, it does not snap to the grid.

I can confirm this is expected behaviour, even with Force Pixel Alignment enabled. Nudging using the arrow keys will always move the layer by 1px (or by your specific nudge amount in Preferences), regardless of current part pixel location.

I hope this helps

[patrick_h_lauke]

Lovely, thanks @Dan C. Any chance you might have time to also look at 

 and see if the copy/paste behaviour (tl;dr: pasting doesn't respect pixel alignment) is also as intended or a bug?

[Dan C]

No problem at all!

I'm not able to replicate the behaviour your seeing in this thread provided, with Force Pixel Alignment and Move By Whole Pixels enabled, both selections and full layers are pasted in the same X&Y locations, respecting Force Pixel Alignment.

Please see this below using a document at 45px x 34px & 150px x 150px, both at 300DPI.

As can be seen, a Quick Shape (rectangle) copied from X0,Y0 in the smaller document is pasted at x0,Y0 in the larger document, a pixel layer or pixel selection is also pasted at the same X&Y locations, with the correct full pixel value for H&W.

Do the DPI's between your 2 documents match?

[patrick_h_lauke]

thanks for looking @Dan C. the DPI of my documents matches. I'll try and do a proper screen recording of the issue and add it to that original thread (and I'll mention/ping you in that discussion there), just to keep it separate.