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jimiclaybrooks
11-13-2012, 10:50 AM
Hey guys,
I've been trying to do a piece of paper with a flame that burns from the center outwards. The problem that I'm having is doing the actual scorching effect. My question is, how can I get the scorching effect to spread as the flame moves across the paper.

jeric_synergy
11-13-2012, 11:29 AM
Back in the day I did exactly this, assuming you mean the paper is GONE in the middle (aka "The Bonanza Effect"). At the time I did it w/SURFACE EFFECTORS, which I believe was supplanted by Worley's ACID, and is now supplanted by one of Denis's offerings (Marker Pen?). Basically a null overrides the Surface settings: you scale it/them up to get the expanding effect, and use nested objects to make the various phases of 'burning'.

So, take a look at Marker Pen.

(Two-to-one Larry has a slick way to do it with Gradients.) :)


+++
EDIT: of course, you could also use Image Maps, but Marker Pen may be the best way to create those animated Image Maps.

jimiclaybrooks
11-13-2012, 11:37 AM
Thanks jeric, and yeah, the Bonanza effect is exactly what I'm after. Also, I'll be cash money that Larry does have a slik way to do it with gradients.

jeric_synergy
11-13-2012, 01:06 PM
Here's another way to create the image map:


Make a white 'sheet' of paper
Turn all lights off
Ambient to zero
Center a spot on the camera, pointing at the paper, with an Cone Angle of Zero (and maybe Intensity=0)
Animate intensity&cone angle to start at the center of the paper, and animate to full coverage

WALLAGH! your animated image map for the Bonanza effect.

mummyman
11-13-2012, 01:17 PM
I think there's a suface procedural called Marker Pen that you can link to a null and animated it's motion / scale. But ah... showing your age, jeric...with Surface Effectors. I remember that one well... along with the Worley "ACID" plugin. That worked wonders. Yes, regular nodes and falloffs work fine for this FX. Oh..if you use the Marker Pen... you can use a turbulence in the layer under it for displacing the edges. Not sure if there's a node hookup. I've always used it in the stackable layers "old" school way of surfacing. Because, well.. I'm old school... Good luck! Love the spot light technique. Simple, effective...why the heck didn't I think of that?

jeric_synergy
11-13-2012, 02:06 PM
Yeah, I'm old, ya punk. :) :beerchug: Yes, you'd definitely want to displace via , uhhhhh, an underlying turbulence layer to get that proper wiggliness in the burning edge. I bet the trickiest bit would be getting that fine line of glowing ember just before the paper 'burns thru'.

I'm not sure how one would do it via nodes, except for Gradient nodes (i.e. pretty much the same as olde school layers). Maybe someone can jump in here. I've never used MarkerPen: if it has an animated radius it'd be a walk in the park.

Two things I miss: SuperGlow and SurfaceEffectors, those were excellent plugins.

mummyman
11-13-2012, 02:22 PM
I'd probably go with after effects, myself....if you have it!!!

jeric_synergy
11-13-2012, 02:30 PM
Yeah, an animated mask would be trivial. Six of one....

XswampyX
11-13-2012, 03:48 PM
You could use The DP node -> boolean to cut out your burning hole, and to texture the glowing edge. Use a jittered cone and move it up through the paper.


http://youtu.be/uKqgD68EnEc

jeric_synergy
11-13-2012, 04:09 PM
Nice. A few particles with an upwards wind and very convincing!

jimiclaybrooks
11-13-2012, 06:43 PM
Thanks guys, this is a great help. Honestly, I'd never heard of surface effectors before. That ones new to me. But the image XswampyX put up is really nice. I'd like to see the gradient burn a little darker and spread out more, but that's just my personal taste. As far as the cone is concerned, that's so amazingly simple. I was going to do a cloth fx/morph thing, but now I may have to go back to the drawing board. I've not had much success with the marker pen tool either, (I'm old school too, so nodes don't treat me all that well). But I'll give it the old college try if it'll get me where I need to go. Again, thanks for the insights, lets see what can be done.

jeric_synergy
11-13-2012, 07:34 PM
jimiclaybrooks, when you get that figured out, please post a sample file package.

jimiclaybrooks
11-13-2012, 07:43 PM
U got it dude!

jeric_synergy
11-13-2012, 08:45 PM
For a very regular (circular) hole, this setup (attached) will allow you to get a color outline of your choice (embers) around an animated hole.

Adjust the color in the Gradient node.

Marker Pen seems very fun. I wonder what the node setup for an arbitrarily shaped 'pen' (i.e., an object) would look like.

Like, imagine a clawed hand leaving marks on a wall. --Somehow, I think my idea is the wrong approach....

109136

jeric_synergy
11-14-2012, 02:10 PM
it strikes me that moving a 'jittered cone' upwards AND rotating it might enhance the illusion....

XswampyX
11-14-2012, 02:58 PM
Not really Jeric_synergy. :(

Think of the 'jittered cone' as a star shape..... you would see the rotation and it would ruin the effect, as burnt paper doesn't un-burn itself.

Like your thinking though.

jeric_synergy
11-14-2012, 04:09 PM
Ahh, my imagination was confusing the persistent effect of Marker Pen with Boolean, which I haven't used yet.

There'd be no 'unburning' with a persistant effect (i.e., it's 'one-way') but the speeding and slowing would be more firelike. D'oh! My confusion.

XswampyX
11-16-2012, 10:58 AM
After a bit more tweaking.....


http://youtu.be/d-xCztjEQ_w

The flames are just the deformed paper layer.

jeric_synergy
11-16-2012, 11:43 AM
Dood, pretty awesome. (What framerate is this? Seems a bit temporally quantized.)

XswampyX
11-16-2012, 11:59 AM
I think it's you tube...?

Here's the original. Any suggestions?

jeric_synergy
11-16-2012, 12:10 PM
What codec is that? My machine coughed it back up. :(

DivX?

XswampyX
11-16-2012, 12:12 PM
Yep. :-) Brilliant quality for the size.

Oooops No. XVID.

Sorry!

XswampyX
11-16-2012, 12:18 PM
Here's the scene to create the mask. Use the mask images to render out in a new scene.