Hi, working in Rhino 9 with materials isn’t a very fast experience and I wonder why does Rhino 9 need to prepare procedural textures for first time use? And why twice?
Look at this material, I added a Gradient texture to the Base Color and waited for it to calculate, then when I also add a gradient texture to Emission it needs to calculate it again. Is that a bug?
And since you probably wonder why that shape looks familiar, and why I need a gradient emitting texture then this is the answer:
This is an ongoiung issue it seems.
For candle flame renders, you could also use a two-polygon plane, and then a diffuse and opacity map, either from a photo source or AI-generated, so each flame looks slightly different. For the wick, usually a black rope material on a bent cylinder suffices, if one needs close-ups.
I wonder if it is possible to combine with grasshopper/kangaroo to “move it with the wind” and set each flame to a different position with that. similar to what I saw someone do with curtains once.
Some renderers have a randomisation feature, to randomise which texture map is used for a given material, so that’s probably the easiest way, if you need, say 17 candles in the photo. On the other hand, simply copying and pasting the material, say, 3 times, and swapping the two texture maps, is taking you only a minute or so.
Happy Easter!
Very nice flames 
But for me it was all about checking R9 and texture creation, so I just came up with a super simple scene. (I do not need a flame for anything)
So if you feel adventurous then please see if you can generate an illuminating texture with gradual lumination and also transparency by using a gradient.
My answer so far is “no” and I ended up with a cheap LED flame from Clas Ohlson instead 
Ah, I see. I am on V8. Have to wait until V9 is an official commercial release before install is allowed. You’ll probably find better LED flames at Nordiska Galleriet in Malmö 
Haha, yeah, if you can’t reach your goal then just change it, LED it is from now on
I think this works just the same in R8 though, I don’t believe there has been mayor changes.
(We are mainly (99%) on R7 still though, so R9 is just a monthly check in to see the progress from my part)
What’s actually happening is we need to recompile and link the material shader after each change to the material. This is unfortunate, but we’re trying to get the correct trade-off with regard to rendering speed and shader recompile wait time. Once recompiled, that specific shader will be cached and won’t need a recompile again until Rhino or your GPU driver is updated.
The messaging is misleading in this case and so when the emission effect is added it looks like we need to wait for procedural textures again, but this is not the case. We’re waiting for the material with the new emission effect to be compiled.
I made a YouTrack item for simplifying the messaging and preventing confusion: RH-91089
-David
