Bloom and Glare resets in-between renders

[Daniel Mikolajčák]

Hello,
could Bloom and Glare from previous render stay in the vfb? In case of re-rendering a small region Bloom & Glare effect disappears from surrounding region that is not being re-rendered.

Not very practical in my opinion.
Greetings,
Daniel

[mmarcotic]

Hello,

afaik bloom and glare needs to be recalculated on each render and if it was remembered, it would cause further problems elsewhere.
Would "Render from last" help you in this case? Should make the bloom&glare calculation much faster for the surroundings outside of the render region.

If it was possible, could you send me a short video of your exact issue? I'm not 100% sure I'm following.

Thanks,
Jan

[Daniel Mikolajčák]

Hello Jan,
Render from last would do the job greatly, that is not current feature right? I cannot find it.

[mmarcotic]

In the VFB, press and hold the Render button (as if you wanted to go to IR through VFB), there is an option "Resume last".
(https://help.c4d.corona-renderer.com/support/solutions/articles/12000035761-how-to-pause-and-resume-rendering-with-corona-renderer-for-cinema-4d-#:~:text=Resume%20Last&text=For%20example%2C%20if%20your%20scene,final%20render%20with%2020%20passes)

Let me know how that works for you,
Jan

[Daniel Mikolajčák]

However this renders over last image, does not work if something changes. Best would be if Corona did not dump Bloom Glare pass around the render region. It does not dump ID pass for example, I don´t understand why all bloom image area has to be dumped to recalculate small area.

hopefully this is understandable

[TomG]

Probably because of this - if you render a region and that region now has a new bright part in the image close to the edge, the bloom and glare from that region would have to spill out into the rest of the area outside of the render region. (Or if a previous bright point was now not so bright, or if the color had changed). In other words, what is IN the region could affect Bloom and Glare outside of the region.

Since Bloom and Glare doesn't take that long to calculate, best thing would be to have it dumped, and recalculated for the whole image at the end not just within the region (is this not what is happening btw, are you saying that the new recalculated bloom and glare only appears inside the region, the rest of the image outside of the region has no bloom and glare?)

[TomG]

Ah taking a look, it's the b&g pass - that's an interesting question, whether the pass should calculate and contain the b&g for the whole image, even if render regions are used. I can see an argument for that being what should happen :)

[Daniel Mikolajčák]

Good Point TomG
I have no problem with Bloom and Glare recalculating for whole image even when a region is rendered. However in case of region render only area within selection receives bloom effect, the rest of the image is ignored.

[Daniel Mikolajčák]

Ah taking a look, it's the b&g pass - that's an interesting question, whether the pass should calculate and contain the b&g for the whole image, even if render regions are used. I can see an argument for that being what should happen :)

Tom, it is not only the pass, I used the pass to visualise it. Even in vfb only render region receives recalculated b&g. I think if "clear VFB inbetween renders" is unchecked, b&g should be recalculated for whole image

[TomG]

I'd agree, the bloom and glare should be thrown out, and then calculated for the whole image afresh and not just for the render region (since things outside the region could cast b&g into it, and things inside the region could cast b&g out of it).

[ramyhanna]

I wanted to bring this back up, as in our office our artists were complaining about this same issue.  If they have to fix something and do a region render, bloom and glare is dumped from the whole image and is calculated just for that region.  It needs to function like the cxr was loaded into the frame buffer and bloom and glare was turned on.  Is there a way to have Bloom and Glare calculated for the whole image, even after the region is rendered?