Hi, after my recent attempt on making realistic clouds (see other topic and tutorial), I have switched to an other fun thing :
This is the result of several days of research about how to make a natural looking wood fire in Blender. As my home is warmed by electric radiators, I plan to use this animation to put an open fire on my TV set for Christmas. It is a classic in video, but I have never seen one done in CG.
The still looks great!.. extremely realistic… although I would say that the animation needs some work despite the fact that it was done entirely with blender and is exceptionally good in that sense.
A few things that you should edit:
Shadows, these need alot of work, the shadows seem to be generated by the fire and are very static.
Sparks, they seem to be weightless, The sparks should possibly fly around a bit more… Also, sparks arent usually constant, but rather appear when the fire is disrupted.
we heat our house by fire and i can add some facts about the sparks, sparks only happen when the fire is disrupted such as when you poke the fire or there is internal tension in the wood that gives way suddenly and then you get flying spark. sparks that go straight up are very rare. usually they fly very quickly to the sides. and even with that said, a lot depends on what type of wood you are burning.
in your animation it seemed that a few chunks of plasma stayed in one spot (such as top left). they should cool/fade out while traveling up and then new plasma should fill the space. but still, this is the very best fire i ever saw from blender!
Thank you for your comments. I will try to improve the sparks, shadows and flames shape. I have mainly worked on the flames material an animation. The fading of the top of the flame gives me nightmares… I tried several kind of masks with more or less success. I wil try something with warp textures or warp node with an animated texture.
@radialronnie you are right about the “plasma” staying in place. It is due to the fact that the flames are meshes animated by displacement textures and Softbody.
I’m wondering if it is possible to apply softbody to meshes used as particles… that could do the trick, because the free lames at the top would never come down, but I fear that it is not possible, because softbody has to bake a constant number of vertices, I think… But I have an other idea, with a rotating cylinder with horizontal transversal axis, made of litlle flames, added to the main shape it could be interesting…
For the almost constant flow of sparks, I tried to match with the only not too bad sound track I had made. As there are many crackles on the sound track, I added many sparks… I will try to add more random to them, and also to add few bigger sparks falling down and bouncing on the brick floor before dying slowly.
I have taken in account your advices. I hope you will like it.
The rendering as been done in Full screen mode, at 1280x1024 (37 seconds per frame in Blender internal) and then encoded in 768x576.
I can’t achieve to get the same contrast level between the original sequence in AVI RAW,and the videos encoded with various codecs. There is always a loss of contrast, even if I increase the contrast before encoding… weird and annoying. You may have to increase a bit the contras in your player (VLC, QuickTime player or Windows Media Player) The last one doesn’t allow ajustments on MPEG files.
It is not the final version, because I have to model some props and change the metal board behind the fire, wich has only the frame modelled and a photo with bump. I have started drawing my own board, before modelling it. Also, Im’ still not happy of the fire. At some moments, I think that the flames look too flat. Maybe I should use closed meshes instead of flat blades. I have to play with lights too…
As the modelled flames don’t emit light by themselves, they are lit by several lamps all around, close to them. the lamps are vertex parented to Vertices of the flames meshes, so they move in all directions while the flames are deformed (they are deformed by displacement texture and softbody, in the flow of a wind effector).
I have also added a random variation on each the Energy parameter of each lamp (not enough, maybe).
The shadows are applied using the same method : several spot lamps casting only (buffer) shadow.
These lamps are in the volume of the flames to avoid visible parallax errors. As the meshes of the flames don’t cast shadows, the lamps can be put inside. Anyway, I could have set the min distance to cast shadows of the surrounding without casting the shadow of the flames.
The rendering time in 720x576 is 27 seconds per frame : this gives less than two hours for 10 seconds of animation (250 frames).
Hi, This project is almost finished. There are still few problemes here and there, but they can only be seen in very close up,and would not be noticeable in a movie. This said, I hate leaving these kind of details in the state, but I fear I can’t spend much more time on this scene.
So, you will find an animated sequence available in many formats, at the bottom of this page :
I have noticed that the visual quality depends of the player used. VLC gives a good result in average. QuickTime players often add a green tint…
In native format, the contrast and light is very good on all my PC and screens, but strangely, once encoded in various formats,I get different contrast and brightness on each machine !
These difference are mailny visible in low light scenes… and it is the case here.
I would like to show the master in Motion JPEG V3 1280x1024, but the file is so heavy : 500MB. It is good as well compressed at 200 MB, but still too heavy for uploading (upload is much slower than download).
If it is too dark, I let you tweak the parameters of your Player… sorry !
