0001500: SVG Does Not Render Propely

(0004805)
neoarttec (reporter)
2010-03-11 01:13

I have identified the issue.

FV-MPP-01.svg does not have "background". The SVG text / objects have nothing behind them. The document properties define the background as black. The text / objects do NOT render with anti-aliasing.

FV-title.01.svg however uses a black object behind the text / objects to provide the black background. The text / objects DO render with anti-aliasing.

When the text / objects in file FV-MPP-01.svg are provided with a background object, as in FV-title.01.svg, the text / objects now render with anti-aliasing.

(0004813)
ttill (developer)
2010-03-12 15:08

If you want anti-aliasing to work with a image having a transparent background you have to add a composite transition.

(0004832)
neoarttec (reporter)
2010-03-17 00:53

ttill what I wrote was, the image has a background colour defined. If you actually open the SVG in something like Inkscape you will see what I mean.

As for the "use a composite transition" sticky tape solution, I have already posted about this. Other users also agree. Why should I have to use a transition to use an alpha transparency? Every other graphic program understands that objects or layers with alpha transparency stacked above others, allow them to show through... without any special modes or transitions being set.

The current way Kdenlive treats this is broken. Consider this, what if I have a clip with alpha but want to layer it over multiple clips? I can't, the transition only allows to one clip, plus, it does not allow transition stacking. If any of the other tracks below have a transition applied, the composite won't work.

If I import a bog standard SVG file, I don't expect to have use a cludge to use it. Other programs understand the file and display it correctly.

(0004833)
neoarttec (reporter)
2010-03-17 00:55

ttill, it seems we have already discussed the issue of alpha transparency.

http://www.kdenlive.org/mantis/view.php?id=1485 [^]

(0004834)
ttill (developer)
2010-03-17 17:36

Well, I fully agree with you.
I just wanted to point out a temporary solution.
Sadly I don't have enough time to work on this issue.

(0006396)
ddennedy (developer)
2011-02-08 08:46

Libraries are used to render the SVG (librsvg if installed or Qt otherwise). I suppose these do not understand the background color and gives us an alpha channel. (Not commenting on the need for composite.)

(0006926)
neoarttec (reporter)
2011-06-20 21:04

A new issue with SVG rendering.
Kdenlive incorrectly renders right aligned text.
.svg file attached.
End-Credits-Text.svg.zip
Add file to a Kdenlive project, open file in Inkscape and compare. Inkscape of course renders correctly.

(0006930)
ddennedy (developer)
2011-06-20 23:05

Re: Kdenlive incorrectly renders right aligned text.

Kdenlive does not directly render SVG. librsvg via gdk-pixbuf or QtSvg via QImage renders SVG. This is not under our control.

Issue History
Date Modified	Username	Field	Change
2010-03-11 00:42	neoarttec	New Issue
2010-03-11 00:42	neoarttec	File Added: Art-Imaginär-1.png
2010-03-11 00:56	neoarttec	File Added: FV-MPP-01.svg.zip
2010-03-11 00:57	neoarttec	File Added: FV-title.01.svg.zip
2010-03-11 01:13	neoarttec	Note Added: 0004805
2010-03-12 15:08	ttill	Note Added: 0004813
2010-03-17 00:53	neoarttec	Note Added: 0004832
2010-03-17 00:55	neoarttec	Note Added: 0004833
2010-03-17 17:36	ttill	Note Added: 0004834
2010-05-01 08:44	ddennedy	Relationship added	has duplicate 0001485
2010-05-01 08:49	ddennedy	Relationship added	has duplicate 0001456
2011-02-08 08:46	ddennedy	Note Added: 0006396
2011-06-20 21:02	neoarttec	File Added: End-Credits-Text.svg.zip
2011-06-20 21:04	neoarttec	Note Added: 0006926
2011-06-20 23:05	ddennedy	Note Added: 0006930

Notes
(0004805) neoarttec (reporter) 2010-03-11 01:13	I have identified the issue. FV-MPP-01.svg does not have "background". The SVG text / objects have nothing behind them. The document properties define the background as black. The text / objects do NOT render with anti-aliasing. FV-title.01.svg however uses a black object behind the text / objects to provide the black background. The text / objects DO render with anti-aliasing. When the text / objects in file FV-MPP-01.svg are provided with a background object, as in FV-title.01.svg, the text / objects now render with anti-aliasing.

(0004813) ttill (developer) 2010-03-12 15:08	If you want anti-aliasing to work with a image having a transparent background you have to add a composite transition.

(0004832) neoarttec (reporter) 2010-03-17 00:53	ttill what I wrote was, the image has a background colour defined. If you actually open the SVG in something like Inkscape you will see what I mean. As for the "use a composite transition" sticky tape solution, I have already posted about this. Other users also agree. Why should I have to use a transition to use an alpha transparency? Every other graphic program understands that objects or layers with alpha transparency stacked above others, allow them to show through... without any special modes or transitions being set. The current way Kdenlive treats this is broken. Consider this, what if I have a clip with alpha but want to layer it over multiple clips? I can't, the transition only allows to one clip, plus, it does not allow transition stacking. If any of the other tracks below have a transition applied, the composite won't work. If I import a bog standard SVG file, I don't expect to have use a cludge to use it. Other programs understand the file and display it correctly.

(0004833) neoarttec (reporter) 2010-03-17 00:55	ttill, it seems we have already discussed the issue of alpha transparency. http://www.kdenlive.org/mantis/view.php?id=1485 [^]

(0004834) ttill (developer) 2010-03-17 17:36	Well, I fully agree with you. I just wanted to point out a temporary solution. Sadly I don't have enough time to work on this issue.

(0006396) ddennedy (developer) 2011-02-08 08:46	Libraries are used to render the SVG (librsvg if installed or Qt otherwise). I suppose these do not understand the background color and gives us an alpha channel. (Not commenting on the need for composite.)

(0006926) neoarttec (reporter) 2011-06-20 21:04	A new issue with SVG rendering. Kdenlive incorrectly renders right aligned text. .svg file attached. End-Credits-Text.svg.zip Add file to a Kdenlive project, open file in Inkscape and compare. Inkscape of course renders correctly.

(0006930) ddennedy (developer) 2011-06-20 23:05	Re: Kdenlive incorrectly renders right aligned text. Kdenlive does not directly render SVG. librsvg via gdk-pixbuf or QtSvg via QImage renders SVG. This is not under our control.