Lucio

Thank you for Sharing.
Very useful workaround for an AP lack I hope will be soon solved.

CLIPPING WARNINGS IN PHOTO PERSONA USING PROCEDURAL TEXTURES
Develop persona allows you to see clipped areas. I have created three procedural texturas to reveal this areas in photo persona.

First procedural texture: Clipping Shadows/Highlights
Here is an example where shadows and highlights are clipped.

Just like develope persona i used red and blue to show the warnings. Red for highlights and blue for shadows.

Second procedural texture: Clipping RGB
This procedural texture shows warnings for each channel when a pixel reaches 0 or 255.
Each channel has its own warning colour. Single colour per channel.
In this example i went too far setting the black level on the green channel.


Usually you will only see warnings in red, green or blue but it is also possible to see cyan, magenta or yellow.
Lets take for example a yellow warning. If you add red and green you get yellow so a yellow warning refers to the red and green channel.
Cyan = Green + Blue
Magenta = Red + Blue


Third procedural texture: Clipping RGB - Black background
Sometimes its hard to see the warnings because they look they are blended whith the image.
This procedural makes the image completly black while the warnings remain in colour.
It is like when you select the levels adjustment and hold down the alt key but in this case the warnings are visible while editing each channel.

If you found this usefull you can download the file at the end or paste this formulas.
First procedural texture: Clipping Shadows/Highlights
var trigger=floor(0.5+abs(average(R,G,B)-0.5)); trigger*R + (1-trigger)*R
var trigger=floor(0.5+abs(average(R,G,B)-0.5)); (1-trigger)*G
var trigger=floor(0.5+abs(average(R,G,B)-0.5)); trigger*(1-B) + (1-trigger)*B
Second procedural texture: Clipping RGB
var rgb=floor(max(R,G,B,1-min(R,G,B))); var red=floor(0.5+abs(R-0.5)); rgb*red + (1-rgb)*R
var rgb=floor(max(R,G,B,1-min(R,G,B))); var gre=floor(0.5+abs(G-0.5)); rgb*gre + (1-rgb)*G
var rgb=floor(max(R,G,B,1-min(R,G,B))); var blu=floor(0.5+abs(B-0.5)); rgb*blu + (1-rgb)*B
Third procedural texture: Clipping RGB - Black background
var rgb=floor(max(R,G,B,1-min(R,G,B))); var red=floor(0.5+abs(R-0.5)); rgb*red
var rgb=floor(max(R,G,B,1-min(R,G,B))); var gre=floor(0.5+abs(G-0.5)); rgb*gre
var rgb=floor(max(R,G,B,1-min(R,G,B))); var blu=floor(0.5+abs(B-0.5)); rgb*blu
clipping_warnings.afphoto

I did change the shorcuts (azerty keyb) as follow
 
 

Lucio,
If you edit an image in the tone mapping personna, you can save the settings, such as exposure, contrast, etc as a new preset. AFAIK, the image needs to be in RGB 8 color space.

Despite what others told above is usually correct (Styles are addable from vector shapes/text), you can add images (bitmaps) with the gradient bitmap tool into a let's say rect shape (no stroke and fill) and add that as a style then into your own created style category. - Presets are another theme, you can create those in the Develop persona.

Until now, I've used Nik software for my B&W (including IR) processing. This same software can be added to Affinity Photo as a free plugin. How-to instructions for adding the plugin are available in these Affinity forums.
I have a free IR book in my on-line eBook Library (all made with Affinity Publisher, by the way).
Also, there are numerous IR articles in my Photo Improvement blog (use the blog's search box). Finally, on this same blog, there's a 12-part Silver Efex Pro 2 tutorial which includes a Workflow section.
Hope you find this useful.