Alpha transparency export differences

[David O'Neil]

Xtreme handles alpha transparency exports differently than other types of exports, and it's annoying. With the attached file, select only the top left outer square and try to export an alpha transparent png from the 'Selection.' Only the square will be exported--the inner shapes won't be. If it isn't exported with alpha transparency, the inner shapes show up regardless of what type of export you select.

I finally figured out that if you select all of the items inside the box, as well as the box, it exports as you expect using alpha transparency and 'Selection.' But this is a big limitation, because that means you can't easily export only a portion of an underlaying bitmap or other object, as you can when you don't use alpha transparency. You can see this for yourself if you try to export the right rectangle on top of the four-color filled shape with transparency--the underlying four-colored shape will not show up in your export unless you do as is done on the bottom objects, and clipview the items to the rectangle. That's a pain to do every time you want alpha transparency output correctly for a selection set!

Therefore, this is a request to make alpha transparency exports work the same as other exports--have everything within the selection show up, even if their boundaries fall outside the selection.

[Charles Moir]

Sorry, but this is doing exactly what it should and what I'd expect. When you select an object to export with alpha channel transparency, it does exactly that - exports the object you selected and nothing else. So selecting just the outer square should export only the outer square.

If you export in a file type that does not support true alpha channel transparency, then it has no choice but to export the square and anything that appears as part of the background (because it can't have a transparent background).

So it's doing exactly what you asking it to do. And yes this means if you want the right hand example to export with background, then by definition you're asking for it to be exported without transparency - and indeed if you select PNG without transparency (i.e. True Color) you get the background as you'd expect.

[David O'Neil]

The approaches Xara now takes for the transparent/non-transparent cases are logically inconsistent with each other.

In the case of transparent exports, you are saying that *only* the objects selected will be exported, whereas in the non-transparent exports you are saying that all objects within the boundaries are going to be exported. That isn't even close to being the same criteria.

To make these consistent with the transparent option now in place, you would need to make it so that only the selected objects were exported in the non-transparent case. Logically, that would entail making everything else the page background color, so any bitmaps that weren't selected didn't show up at all.

This inconsistency causes a lot more work in the case where you want to only export a portion of a project which includes transparent objects/bitmaps. The only way I can figure out to do it is to clipview everything, as shown. It is a pain. That's why I'm asking for this change--to make Xtreme easier to use and more logically consistent with itself.

[handrawn]

Sorry David - I don't see how you can extrapolate 'behaving differently' into 'logically inconsistent' in this case.

And they behave differently for good reasons it would seem, which Charles gave, that make sense to me.

[BobInce]

There is a slight inconsistency. In the no-alpha case, any objects in the background do have to be rendered to provide some kind of background as a pragmatic matter, but objects *above* the exported object are rendered too. These are not present in the with-alpha export. If you did a non-alpha export of a background image with an alpha export of the foreground image placed above it, you'd have two copies of the foreground image.

To me it would make more sense for the non-alpha export to include elements below it in the z-order, but not above it. This is the reverse of David's suggestion, which would effectively turn the Export function from 'Export object' to 'Export portion of entire drawing corresponding to object boundary', a less useful feature IMO.

[David O'Neil]

This ... would effectively turn the Export function from 'Export object' to 'Export portion of entire drawing corresponding to object boundary'...

Actually, that is exactly the way it now works in the case of non-transparent exports. Many users have indicated they use it to export portions of their drawings. It is very useful - try it!

...and they behave differently for ... reasons ... that make sense to me.

If you haven't tried to export just a portion of a drawing that has transparent objects in it using true-color + alpha, please don't jump in. The reasons given don't make sense, especially as it makes Xtreme harder to use in that situation.

[handrawn]

Ah the joys of public debate

David - I have been using the export function png with alpha transparency for the last five years - xara has always been like this [as far as I know].

No way would I want objects in my drawing within the alpha boundaries to be exported with it - its bad enough for me remembering they will be exported in true color mode - but anyway the point is surely as Charles stated [in so many words] -its either with alpha channel or it aint.

[sgiff]

Have to agree with Charles here, the alpha export works exactly the way it always has and it works correctly. Things have not changed. You can't expect it to behave any other way. I wish we had more options than just PNG for transparency export for example PNG's hold transparency a different way than TGA or Tiff. Some of my programs I use like Cinema 4D prefer TGA format at least they handle them better so It would be nice to see a true Alpha channel option as an export feature and not just transparency export.

s.g.

[David O'Neil]

...its bad enough for me remembering they will be exported in true color mode

Interesting. Software companies have spent hundreds of millions of dollars trying to make it so that software gives you a 'what you see is what you get' experience, and now you are saying that in the case of true-color partial exports you aren't in favor of a WYSIWYG experience. I guess you really can't please all of the people all of the time. As a curiosity, how do you handle exporting partial drawings that have transparent objects whose boundaries extend beyond the areas you are trying to export, when you want those (semi-)transparent areas to be exported? In the method I'm suggesting, all you'd have to do is turn off the layers you don't want to show - again, a WYSIWYG experience which you don't seem to be in favor of.

[handrawn]

Interesting. Software companies have spent hundreds of millions of dollars trying to make it so that software gives you a 'what you see is what you get' experience, and now you are saying that in the case of true-color partial exports you aren't in favor of a WYSIWYG experience.

I did not say I am not if favour of it - I said I have to remember it and I find this irritating - but I also know that it its a feature that many xara users need a lot - and so I have not, and never would suggest that xara change it.
'Select objects and export them' is wired into my psyche 'select objects and export them and get something else as well' is not - but swings and roundabouts xara makes up for it in many other ways

As a curiosity, how do you handle exporting partial drawings that have transparent objects whose boundaries extend beyond the areas you are trying to export, when you want those (semi-)transparent areas to be exported?

If I read your first post right - the same way you do

In the method I'm suggesting, all you'd have to do is turn off the layers you don't want to show - again, a WYSIWYG experience which you don't seem to be in favor of.

WYSISYG depends on what you see. I don't see transparent areas [because they are transparent] they are simply 'not there' - therefore I don't want unselected objects that fall within them to be exported too - that is not WYSIWYG to me. If I want them I'll select them