Default color for a new correction layer or a mask is not white anymore

[NotMyFault]

2 hours ago, R C-R said:

I am not sure of the "we" you are referring

„We“ stands for all who use the term partial selected pixel, and share this common understanding for this term:

• From the pixel, use its RGBA value (or respective color channels depending on color format) partially, meaning weighted proportionality to given transparency/alpha value for this pixel in the selection.
• For color channels, gamma correction can apply depending on how the selection is used. This means that the numeric result could show different values than a linear proportion if gamma correction plays into the game, e.g. when pasting from a copy made with active selection.

I assume you and Walt are not in this group. 
You are welcome.

[R C-R]

4 hours ago, NotMyFault said:

„We“ stands for all who use the term partial selected pixel, and share this common understanding for this term:

What makes you think that phrase is commonly understood to mean anything other than as it would be in the most literal English language interpretation, that being that a pixel can actually be partially selected?

[NotMyFault]

Because context matters if you try to evaluate the meaning of a sentence (language).

My partner was not amused when a big tech company started to use her name as activation keyword to trigger voice commands. Before it was 100% the name of a human. Since then it is a keyword to drop a wish to a virtual butler. She had to learn not to get upset every time her brother asked “hey xxx close the windows” in an house with full home automation.
 

[Old Bruce]

7 hours ago, NotMyFault said:

She had to learn not to get upset every time her brother asked “hey xxx close the windows” in an house with full home automation.

In my family 'her brother' would have built/bought a house with full automation just to tick his sister off.

[R C-R]

11 hours ago, NotMyFault said:

Because context matters if you try to evaluate the meaning of a sentence (language).

There is no context in which "partial pixel selection" or "partially selected pixels" makes any sense (because as I think we can all agree pixels are the smallest possible image unit), yet people keep using those phrases in contexts like describing what marching ants select as if the selection could include only part of one or more pixels.

Short version: "Partial selection" or "partially selected area" or the like is fine; the other two are not.

[NotMyFault]

We agree to disagree.

What would be in your thoughts an short, exact name for pixels within a defined area having partial transparency by selection?

 

[R C-R]

7 minutes ago, NotMyFault said:

What would be in your thoughts an short, exact name for pixels within a defined area having partial transparency by selection?

Just call them what they are, "selected pixels." A property like partial transparency is something that can be applied to them, nothing more. Simple, straightforward, unambiguous terminology whose meaning should be clear in any context.

[NotMyFault]

28 minutes ago, R C-R said:

Just call them what they are, "selected pixels." A property like partial transparency is something that can be applied to them, nothing more. Simple, straightforward, unambiguous terminology whose meaning should be clear in any context.

Are you dodging the topic?  I'm asking specifically for a name directly expressing that property.

[R C-R]

33 minutes ago, NotMyFault said:

Are you dodging the topic?  I'm asking specifically for a name directly expressing that property.

I am not dodging anything. The name for that property is "transparency," or if you prefer "opacity."

This should not be that difficult to understand. A property (or if you prefer an attribute) of something is not that thing itself.  This applies to anything, not just pixels & their properties.

If you can't see that, I don't know what else I could say to make it any clearer.

[Old Bruce]

Partly selected pixel does not refer to the area.

It refers to the information that area has. How grey is the pixel? Select 40% of that grey. That pixel has been 40% selected.

[R C-R]

1 hour ago, Old Bruce said:

That pixel has been 40% selected.

Nonsense. All of that pixel has been selected. This should be 100% obvious because a pixel can have only one color or level of opacity. So for example it cannot be just 40% some shade of grey & 60% something else. An area of a document can be, but that is an entirely different thing.

This is why the help topic previously quoted (twice now, I think) refers to partially selected areas, not partially selected pixels.

[Old Bruce]

Can we please take it as given that the online help is poorly written?

Think of it as a one gallon bucket with a pint of water in it. I want to know what 40% of the contents' volume is so I can have some milk. 40% of the pint means ....

Oh hell I am not going to explain how my old Imperial gallon has five American pints in it, no Imperial or American Gallons.

Think of it as a 4 litre bucket with a 200 CCs of water in it. I want to know what 40% of the contents' volume is so I can have some milk. 40% of the 200 CCs means .... 80 CCs Another bucket has 500 CCs of water, 40% of the 500 CCs.... 200 CCs 

My first 'pixel' that is 40% selected has 3.92 empty litres in it the second has 3.8 empty litres.

[NotMyFault]

1 hour ago, R C-R said:

to partially selected areas

How do you define area?

• set of pixels in x/y axis ?
• Which layers?
• How to deal with opacity (in layers and selection)?
• what means partially?
  • some pixels included, others excluded?

Edited September 5, 2021 by NotMyFault

[NotMyFault]

It might help to have a look over the fence.

 

1. GIMP uses the term partially selected pixels 
   • http://tinf2.vub.ac.be/~dvermeir/manuals/gimp/Grokking-the-GIMP-v1.0/node43.html#SECTION001217000000000000000
   • https://www.linuxtopia.org/online_books/graphics_tools/gimp_advanced_guide/gimp_guide_node43_006.htm
2. A book about Photoshop uses the term, too
   • https://www.oreilly.com/library/view/photoshop-cc-the/9781491905593/ch04s05.html

[R C-R]

43 minutes ago, Old Bruce said:

Can we please take it as given that the online help is poorly written?

Much of it is, but in this instance it is not.

43 minutes ago, Old Bruce said:

Think of it as a 4 litre bucket with a 200 CCs of water in it.

Why would I think of it like that? A pixel is not like a bucket. A pixel cannot be partially filled with color; it cannot be subdivided into smaller units of color or opacity.

42 minutes ago, NotMyFault said:

How do you define area?

In the usual geometric way, as the extent in some space occupied by something. How do you define it?

[R C-R]

Here is the thing about this that no matter how I try to wrap my head around I cannot:

Even I accept that just part of certain pixels can be selected, then what? Each of those pixels still has just one set of properties so for example how could I sample just 40% of one of those pixel's greyness (or opacity or color), much less apply it to just part of that or any other pixel?

[NotMyFault]

6 hours ago, R C-R said:

Here is the thing about this that no matter how I try to wrap my head around I cannot:

Even I accept that just part of certain pixels can be selected, then what? Each of those pixels still has just one set of properties so for example how could I sample just 40% of one of those pixel's greyness (or opacity or color), much less apply it to just part of that or any other pixel?

Now you are on the good road again 👍🏼 

6 hours ago, R C-R said:

how could I sample just 40% of one of those pixel's greyness

It is called transparency. Or alpha.  It is explained in more detail in the GIMP documentation shared earlier.

The link explains it for the specific case of anti-aliasing. Which is nice as it bridges to the part how partial pixel area gets transformed to an alpha value (percentage of areal coverage).

Even if GIMP, PhotoShop and Affinity are different implementations, there are unanimously sharing the same underlying math and Logic. Otherwise it would be impossible to use and render images consistently.

http://tinf2.vub.ac.be/~dvermeir/manuals/gimp/Grokking-the-GIMP-v1.0/node36.html#SECTION001112100000000000000

Alternatively, Figure 3.11(c) illustrates the concept of antialiasing. Here white represents a pixel which is fully selected, black one that is fully unselected, and gray represents partially selected pixels, where the level of gray indicates the percentage of the pixel that falls inside the selection. Thus, a lighter value of gray indicates a more fully selected pixel and a darker value a less selected one. Assigning gray values to partially selected pixels has the effect of visually smoothing the staircase effect illustrated in Figure 3.11(b), which is why this is called antialiasing.

The way antialiasing is actually implemented is by using the layer's alpha channel.  Alpha channels were introduced in Section 2.2 and a more comprehensive presentation of them is given in Chapters 4 and 5. However, for the purposes of discussing antialiasing it is sufficient to know that the white pixels in Figure 3.11(c) represent pixels that are fully opaque, the black pixels those that are fully transparent, and the gray pixels those that are partially opaque (or transparent).

 

in my words:

• Take the RGBA values of every pixel in the selection, into a working buffer.
  Multiply the alpha value of every pixel with the alpha value of the selection for that pixel, and write the result it onto the working buffer.
• If an edit action is executed, apply the usual alpha composition blend formula to get the result, and write it to the selected layer. The working buffer is handled similar to an layer placed virtually on top of the layer stack.

 

Edited September 6, 2021 by NotMyFault
Added screenshot and excerpts of gimp documentation

[R C-R]

8 hours ago, NotMyFault said:

14 hours ago, R C-R said:

how could I sample just 40% of one of those pixel's greyness

It is called transparency. Or alpha.

Whatever you call this property, a pixel can have one & only one level of it. So whatever you sample, it is 100% of that property of that pixel, not 40% or any other percent of it.

Antialiasing in no way overrides or circumvents this; all it can do is to change all of a pixel's properties to the same values. It cannot be applied to just part of a pixel or divide pixels into different regions or areas.

The more I think about this, the only interpretation of "partial pixel selection" that makes any sense to me is it means some pixels are (fully) selected & others are (fully) unselected; IOW, part of the pixels of the document, image, layer, or whatever are included within the selection & the others are excluded from it.

This is consistent with the idea that a pixel is the smallest unit an image can have, & that consequently every property of every part of a pixel must be the same everywhere in that pixel. It also explains why the Affinity help topic refers to partially selected areas rather than partially selected pixels.