Another thread about Resize Canvas: anchor points making my brain hurt

[nickbatz]

Please mansplain me:

I wanted to add 1/2" of blank pixel space to the top of my damn picture to work with.

So the first thing I did was set it to inches. Then I unlinked the height and width.

Okay, so where does the anchor point go? I tried both the bottom and top center and it didn't seem to be reading my mind correctly.

To be clear, I actually was able to get it to do what I wanted, I'd just like to understand how this works (or more specifically, what I did). You'd think that if one point is anchored, the canvas would grow on the opposite side. So for example anchoring the bottom left would logically add space to the top and right sides.

Or in this case, anchoring to the bottom center should add space to the top. But is that what happened?

Right?

TIA

 

[nickbatz]

As an aside, I learned something that's probably obvious to other people - that if you have pixel layers that continue off, say, the top edge of the canvas, then... hello... more of what was hidden by the previous edge will be displayed when you add more top edge.

I love happy accidents like this!

So the moral of the story is not to rasterize and trim until the last stage if you want this behavior.

Okay, okay, the important thing is that I understand what I'm trying to say.

[Aurea Ratio]

I am pretty tired, so bear with me - it might be as good as mansplaining though 🙂

In Photo? It is an old type of illustration you see, imagine arrows pointing out from the bright square; that is the image you have, the not so bright are the canvas to be added:

Not great:

 

Better:

To add 8000 pixels to the top alone, this should work. Unlink first:

Edited February 12, 2024 by Aurea Ratio

[nickbatz]

Thanks, yes, in Photo.

You're confirming what I thought, and I don't have the excuse that I'm tired.

I'm not sure why it seemed to be doing whatever it wanted rather than what I was thinking.

[Aurea Ratio]

Just now, nickbatz said:

Thanks, yes, in Photo.

You're confirming what I thought, and I don't have the excuse that I'm tired.

I'm not sure why it seemed to be doing whatever it wanted rather than what I was thinking.

Maybe you are tired? 🙂

I updated my post with an illustration of how it works in Photoshop - the arrows make all the difference. It the code works, of course. 🙂

[loukash]

13 hours ago, nickbatz said:

I learned something that's probably obvious to other people - that if you have pixel layers that continue off, say, the top edge of the canvas, then... hello... more of what was hidden by the previous edge will be displayed when you add more top edge.

Cropping in Affinity is non-destructive, and… 

13 hours ago, nickbatz said:

I love happy accidents like this!

… it's definitely "by design".  

Speaking of which:

13 hours ago, nickbatz said:

I wanted to add 1/2" of blank pixel space to the top of my damn picture to work with.

You can just as well use the Crop tool to achieve exactly the same result interactively and "live" on canvas. While the crop dimensions in the context toolbar are in pixels, the fields can do all the math for you based on the DPI value of your document. So you can simply type "+0.5in" to the canvas pixel height field in the context toolbar, press the Tab key to apply the new field value only without leaving the crop mode, then move the crop frame so that it snaps to the bottom of the canvas. "Snap to spread" must be enabled, of course.

[nickbatz]

2 hours ago, loukash said:

Cropping in Affinity is non-destructive, and… 

Right, but if you Rasterize and Trim an image that was hanging off the edge of the canvas, it is destructive.

I make my pictures out of several images, so this can be important if - as in this case - I see that the picture is feeling squashed at the top and I need to extend it.

 

2 hours ago, loukash said:

… it's definitely "by design".  

I mean the result was a happy accident. You'd have to see the picture to see what I'm talking about.

 

[loukash]

50 minutes ago, nickbatz said:

if you Rasterize and Trim an image that was hanging off the edge of the canvas, it is destructive.

Of course. It's an option for those users who need it.

[nickbatz]

2 hours ago, loukash said:

Of course. It's an option for those users who need it.

You say of course, but I'm still discovering things about the program.

And I suspect most people who use it are too, they just have more shame than I do.

[loukash]

2 hours ago, nickbatz said:

I'm still discovering things about the program

Oh, so am I.  
I've always been more the typography and graphics guy when it comes to "digital design", while I still prefer to draw illustrations the "old school" way by hand on real paper, and just scan them when finished.
So I'm not necessarily familiar with all possibilities of digital pixel manipulations either, all the filters, blend modes, brushes etc. etc.