Bloom: Cross-fading // Elements out of stage cause errors

vvvv beta general
1

Hey Guys,

we’d like to use the Bloom-Effect for our installation. We have objects moving around. They also leave the stage and come back later on.

These objects should get the Bloom-Effect after some time. We want to switch the effect between on and off with cool cross-fading.

When our objects leave the stage the bloom effet seems to display error (see the scrrenshot).

Our questions:
1) Is it possible the cross-fade the bloom effect?
2) Does the effect have bugs with objects leaving the stage?

Thanks!
Johannes

bloom-bug.JPG (44.2 kB)

2

Hi, some explanation to problem #2:

The Bloom effect works excellent, as long as the object (in the screenshot the lovely “v”) remains within the stage, ie. within the object it is mapped upon.

But as soon as you move the “v” a bit out of sight - even if it is just a tiny bit on one axis - you’ll see some stripes that seem to be an error in rendering.

Is this a bug and is there any possibility to avoid this effect?

Thanks again!
derdaani

3

Can’t anybody help me? I now attached a patch, too.
The error seems to beo caused by the value of the blur amount (0).

THANKS

Bloom(help)-Error.v4p (15.4 kB)

4

Hi,

you should use the blur shader effect combine with a blend shader effect. I don’t like the blur shader this is why I try a different solution.

5

Hi

this blend shader from the bazaar has lots of great techniques for crossfading textures:

http://vvvv.org/tiki-download_file.php?fileId=785

you’ll want to crossfade between your bloom output and your original texture.

that ‘striping’ behaviour is natural with the blur as i think when the blur is at 0 it will just sample individual pixels and stretch them across the whole image, and as you increase the blur amount this stretch distance decreases, i think.

i don’t think you can properly use bloom without any blurring of the pixels first, however you can use an alpha blend on your bloom shader and group this with the original image , as in the attached file.

Hope that helps.

bloom+blend.zip (47.1 kB)