"-alpha on" sets bad value top-left

[anthony]

Yes I have gone though a spate of IM Example updates, and fixes. As well as documentation for the -channel 'Sync' flag.

For example I have added a number of new items to thumbnail 'fluff' examples. Such as using Morphology Distance, or 'True Feathering' to generate a soft edge. And using a Blurred -rasied edge to generate a highlight for a 'Bubble Button' effect.

See Bubble Button
http://www.imagemagick.org/Usage/thumbnails/#bubble

It may take a day for these last few updates to filter though.

[fmw42]

Anthony,

Nice exampe --- Bubble Button.

I had been experimenting with that for a while now and could not work it out.

Been trying to do something like the following:



Can you get a similar effect (with or without the flash in the upper left)?

[anthony]

I know exactly the web site that example comes from... And it is a very nice example. Looks like a bubble of glass sitting on top of the image.

The effect is tricky and uses a combination of edge darkening and internal highlights. That 'flash' in the corner is important for the effect to work, though it is a bit over done. A bit like a 'aqua filter'
as given in IM Examples Advanced
http://www.imagemagick.org/Usage/advanced/#aqua_effects

UPDATE: I have now re-written 'Aqua_Effects' to better explain the technqiue,
and also generated a thumbnail version of the example to generate a 'glass_bubble' type result.
http://www.imagemagick.org/Usage/thumbn ... ass_bubble




This however is getting off topic.

[anthony]

Slow incremental improvements!