Hello, I have noticed a behavior in Krita that misses me, I am not sure if it is a bug, but I think it should not work as it does. It happens in krita pre_alpha 3.0, I have not been able to try it in the stable version, but I would bet that the same thing happens. The fact is that when you use the vanishing point of the assistant tool. When you uncheck the box from the view menu, show painting assistants, you stop seeing the painting assistant but you continue to see the preview of the assistant, everything is correct, but when you uncheck the option ,show assistant previews, with the show paint assistants box marked , the two stop seeing, not only the preview of the assistant. I think it should work just like the concentric ellipse or perspective does. Where you see what you have marked and stop seeing what is not marked, this way I can draw without being disturbed by the preview but seeing the assistant. In addition, there is another problem, I don't know how to reproduce it exactily, but the fact is that if you play by unchecking those boxes, from the assistant tool or from others tool, for example the brush tool, there are times that the menu boxes are not updated, this results in the boxes are marked and paint assistants are not seen and if you uncheck them is when they are seen. This case can occur with any of the modes of the assistant, not only with the vanishing point as with the previous case. The first case I do not know if it is a bug or is a strange design, the latter sure is. Thank you so much for your attention.

For the first part, I think you've misunderstood the significance of the vanishing point 'radial lines'. They are an additional aspect of the vanishing point and no other assistant has anything like them. They are a sort of 'visual aid' to help you see where the vanishing point is, because it can be difficult to find it when there is lots of image content. Personally, I think the operation of them in the Assistant tool mode is logical and understandable but maybe that's because I'm used to how they work.
The vanishing point does work like the ellipse, but it has extra visual aids on it.
When using the assistant tool, there should be no preview lines because you're not painting. However, the vanishing point has the radial lines as a guide to its location.

For the second part, I have seen this as well. It is possible to have a situation with the Assistants tool where the operation of the View -> Show Painting Assistants box is inverted and this can be 'fixed' by deleting an assistant. I haven't yet figured out how it gets into this situation.

There is an additional problem where adding more assistants makes an ellipse tool lose its preview when using a painting tool. This is repeatable and the 'bad' ellipse assistant can be saved in an assistant file. It seems to have a malformed structure.
Formal bug reports will be needed.
A formal bug report will be needed.

Edited: I confused the ellipse assistant (no preview line) with the concentric ellipse assistant (a preview line).

Bug report: https://bugs.kde.org/show_bug.cgi?id=417792

Hello again, I think I understand what you are saying, but I think I have explained myself badly. Basically, being with the brush selected and outside the assistant tool, I understand that by unchecking show assistant preview from the menu view, only this the preview assistant should disappear, as with the fisheye mode or concentric ellipses, for example, not the preview assistant and the paint assistant (in this case, radial lines). I don't see that this way makes much sense. You should be able to draw seeing the radial lines but without the preview assistant, as in the other cases. or I'm wrong? I do not know how to upload images or videos to explain myself better, if it's possible and you tell me how, I upload it. Thank you very much again for your attention.

I think I now understand what you want to see and do.
Those radial lines on the vanishing point assistant are turned off by both the Show Painting Assistants and Show Assistant Previews. I think this is because they are a special case.
Remember that the vanishing point is literally a point and that point is shown (along with the ellipse of the ellipse assistant and the line of the ruler assistant, etc.).
If you want the radial lines to be shown as part of the Show Painting Assistants view then you'd have to ask for a change to be made. That may or may not be accepted by the developers after consultation with other users.

You can't upload images to this forum but you can display them using links to various image storage websites, such as Imgur and any of the many others that are out there.
You can display such images here, with a width limit of about 710 pixels (I'm not sure if i remember that figure correctly), by using the img tags so that it looks like this:



You put your own image storage website location in there, then check it with the Preview button.

For larger images, you can post the link itself. To share .kra files you can use a file sharing service such as Dropbox, Google Drive, etc. and post the link.

Hi, thanks for your reply. I see then that it is a design decision. It is strange, all modes of the same style, those that I think are usable not only to draw geometries, but also as visual reference (concentric ellipse, fisheye and perspective) work the same way, except the vanishing point, just the one that, in my opinion, is more useful only as a visual reference (without using the snap or the preview of the assistant), since it allows you to build a reference world with one, two or three points of perspective. I do not see very well the reason, why this design makes it precisely the radial lines of the vanishing point that are not allowed to see without assistants preview (for example when you do not want to use snap and just want a visual reference). If I just wanted to see a point as a reference only, it is easier to draw a point, than to have to draw all the radial lines as is the case if I want to see the radial lines as a reference, these lines are made mainly for it, isn't it?. I will think about making a suggestion. However, even if the design was good for some workflow that I cannot see, I believe that the system is not correct, because it is not coherent, checkboxes should do what this say do, and if not, indicate the exception of somehow, more than anything, because by not being coherent with the rest, it makes people fall into the understandable mistake of to think that it is a bug, as has happened to me. Thank you very much for everything and greetings (and excuse my english please ).

Hello again, sorry for the trouble. I've been inquiring to remember. I have verified that the radial lines of the vanishing point mode have the option of line density and opacity. I wonder why they would have that option if they were only to find and place the central point, or in any case use it only with the preview of the assistant and snap. I think it is intended to be used also as a visual reference and not only as a point or as an aid to the snap with the preview. I don't know if I can explain myself well. Well, I just wanted to comment on this because it seemed interesting and demonstrative. Thank you very much again.

It's no trouble at all. You've made some valid points and raised an interesting question.

The radial lines (and angular line density) are a special feature of the vanishing point assistant, unlike anything in the other assistants.

For those radial lines, my personal theory is that these seem to be constructed using the same process as the assistant preview lines and so it's a technical/logical consequence that they are removed when Assistant Preview is turned off. That's just me speculating.

I suggest that you summarise and simplify your points to propose that the radial lines are not removed when Assistant Preview is turned off and post that in the Krita Development section: viewforum.php?f=288 for discussion. You might get support and agreement and you might not. The worst that can happen is that the developers say 'no' . If you don't ask for anything, you don't get anything

Ok, maybe I will . Thank you very much again.