Bump Converter

[Noah45]

I may have missed the discussion, and search revealed little.

How and why Bump Converter?

thanks.

[pokoy]

Color and Bump are two different channels in Max (hence the Bump amount parameter in the output rollout which handles bump specifically) and some maps produce different or no bump at all. With this map, you can 'force' bump to render based on color output even if the map doesn't provide any bump channel information (such as AO, for example). Another really useful side effect is that you can use all blending modes of the composite map and color correction on bumps.

[cecofuli]

Try to use Cellular map inside the bump channel with and without CoronaBump ;-)
Without, the bump is inverted.

[sprayer]

cecofuli so coronaBump map only replace invert check box in output rollout?

[maru]

cecofuli so coronaBump map only replace invert check box in output rollout?

No, it takes whatever is plugged into it and treats it like regular black and white RGB information, just as if you plugged a bitmap into the bump slot.
Another example is using the color correction node - it just does not work with bump. If you use the bump converter, it will magically start working as you would expect.

[Njen]

Check out the image in my post about the issue:
https://forum.corona-renderer.com/index.php?topic=13492

Bump Converter fixes this.

[Nejc Kilar]

cecofuli so coronaBump map only replace invert check box in output rollout?

No, it takes whatever is plugged into it and treats it like regular black and white RGB information, just as if you plugged a bitmap into the bump slot.
Another example is using the color correction node - it just does not work with bump. If you use the bump converter, it will magically start working as you would expect.

Could you please explain to us why the color correction node does not work? What kind of sorcery is going on here? :)

[sprayer]

Check out the image in my post about the issue:
https://forum.corona-renderer.com/index.php?topic=13492

Bump Converter fixes this.

It not worked only with empty color slots and with only color maps, if you plugged textures or any maps like noise, cellular etc it will work fine

[sprayer]

cecofuli so coronaBump map only replace invert check box in output rollout?

No, it takes whatever is plugged into it and treats it like regular black and white RGB information, just as if you plugged a bitmap into the bump slot.
Another example is using the color correction node - it just does not work with bump. If you use the bump converter, it will magically start working as you would expect.

i am not sure why we need to use color correction node for bump if we can use output rollout in the same texture and it work with color correction just don't give result for bump

[maru]

Could you please explain to us why the color correction node does not work? What kind of sorcery is going on here? :)

Autodesk Sorcery.

@Sprayer - I think neither color correction will work nor output rollout with bump. The bump converter just makes everything work as expected.

[PROH]

@maru - have you tried to use it with the tiles-map? I can't make it work. Just like it doesn't work very well with greyscale bitmaps. ...or maybe I'm overlooking something?

[Marijan]

Hi, I have a question about using noise map in BumpConverter.

In the attached examples you can see that BumpConverter does something to mapping of noise map.
If I change object XYZ to explicit mapping in noise map coordinates, and map objects with same UVW modifier it works as expected.

Is this normal behavior?
Should we avoid using some procedural maps in bump converter for any reason?

[pokoy]

Good catch. But shouldn't the noise look different anyway? If it was mapped in Object Space I'd expect it too look like what the BumpConverter looks like... If you used World Space then BumpConverter doesn't seem to pick it up properly.

[Marijan]

I see your point but same thing happens regardless of using object space or world space

[romullus]

Could be a bug with bump converter. Could you post it in bug reporting board?