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[edit] Separate and Combine Nodes Categories

Do you think that separate and combine nodes should have their own subheaders like this?

1. Combine
   1. RGBA
   2. HSVA
   3. ...

1. Separate
   1. RGBA
   2. HSVA
   3. ...

--BeBraw 19:34, 27 November 2006 (CET)

imho, yes, because from a user's standpoint, they are functionally two very different things. See Sandbox/Compositing for my thoughts on how and why the manual should be organized.

my only crit is that we should talk about separating before combining back; not having used the combine nodes, I guess they take indiv channels; so introducing the sep. channels as ouput by the sep. nodes makes more sense.--Roger 15:33, 5 December 2006 (CET)

That sounds reasonable. I will change it at once. --BeBraw 19:12, 5 December 2006 (CET)

[edit] Need RGB to BW node?

I am having a hard time coming up with a situation where we need the RGB to BW node. Every rig I come up with, with RGBtoBW feeding something works just as well just bypassing it and plugging the image in. I know the socket colors are different, but the receiving node seems not to care. Help! Someone come up with a practical use for this node, please. I think it has something to do with multiplying each R x G x B x A to produce a shade of gray between 0 and 255. But I can't think of a practical use...maybe where an image has an alpha channel that is very different from the colors???? But why? The only note I found in release notes is:

- Links now can be made between any socket type. The nodes recognize amount of channels, and will convert types if needed. Conversions from RGBA to 1 channel will use the 'RGB to BW' formula.

Also note that conversions only happen when required. So you can blur an alpha channel, filter it, and put this in a 1-channel socket without any conversion to happen, which saves memory & cpu time.

Which sorta indicates that this node is not needed anymore...

Yes, i mentioned this on another talk page somewhere else (can't find it right now) already.

---

I didn't stumble upon a situation where I needed a RGB-to-BW node since the change. The only usage I see is if you want to e.g. directly output a RGB image or material somewhere in BW without using a ColorRamp (or similar) node - so a reference description of it should still be in there - jsut in case :) --Hoehrer 20:13, 5 December 2006 (CET)