Document Properties 'Opacity' (Inkscape)

[Jaws]

I commented in the contest thread about why my rectangular background with rounded corners didn't seem to be rounded.

Turns out if you want to set the 'Background Color' in Document Properties to something other then 'white' (which isn't actually white, it's just transparent or Alpha (opacity) =0, then the exported image will get the color too, if you choose to export the 'Page'.

To avoid this, always have opacity = 0 in the document properties or export the drawing (if it's the only drawing in the current Inkscape document) or export the 'Selection' which then needs to be selected.

The reason why this happened to me is that I use a background color so it's not so bright at about 80% opacity. Also I'm used to exporting as a 'Page' so I can create blur effects that extend passed the page, otherwise the blur tends to 'shrink', allowing a different color to bleed through the edges.

I hope that all made sense.

Cheers

[lunoob]

Jaws, you're a hero.

This is exactly what this forum is needed for.  We noobs need this kind of advice.  Many thanks!

[Digitante]

The reason why this happened to me is that I use a background color so it's not so bright at about 80% opacity. Also I'm used to exporting as a 'Page' so I can create blur effects that extend past the page, otherwise the blur tends to 'shrink', allowing a different color to bleed through the edges.

I assume you mean that you want the blur that extends past the "selection" or the "drawing", but is contained within the "page" -- because in my experience all that these choices do is define which part of the drawing will be rendered to pixels, so it'll cut off sharply, no matter what the drawing is doing over it.

By the same token, selecting a rectangle option and exporting "selection" won't just export an image of the rectangle, but also anything that is rendered over it (i.e. you don't have to select the stuff on top in order for it to export).

In yet more words: the choice of "page", "drawing", "selection", or "custom" is a geometric selection, not a logical one.

[Jaws]

Exactly. I can extend the blur past the edge of the 'page' but have it cut off when exporting the bitmap.

To put it in visual terms and perhaps easier to understand for everyone, it's the difference between the following on a 450 wide by 300 high page size...

The tan rectangle is 450x150, centered and aligned with the bottom of the page.



If I blur the tan color with 5% you get this, which as can be seen the black background is bleeding through the tan blur...



But extending the tan rectangle past the edge of the page...



.... and exporting the page you get that sharp cut off...



.... instead of exporting the drawing...



Exporting a selection, as long as it is inclusive of the area desired, would be the same as exporting a page. I just find it easier to export as a page.

Cheers

Oh yeah, I forgot, thanks Lunoob. You're welcome.