Y'know, Necro, I'd been wondering the same thing. (not if I know, silly, but how to make explosions! )
Anway, the following is nothing but untested, unproven, theoretical ramblings at 6:40 in the morning (who takes 20 minutes to connect to an ISP, and no, I wasnn't getting busy signals?) I'm planning on sometime in the future making a trailer with explosions, so I need to figure this out...
For still images:
1. enter photoshop. You can simply draw on the image, if you think you can draw a decent explosion. Or, you can go find a picture from somewhere of an explosion and layer that on top. The latter would probably make for a more convincing result.
For movies (or still images also):
1. if you don't have a movie-editing piece of software (like me) you have to do it all in your 3D app, essentially. Martin Turner's suggestion sounds cool, and not too hard. Lens flares are easy to set up and animate in Infini-D, and depending on your skill level, you can model some debris and make a whole lot of junk fly out of the explosion. Alternately, you can use the less-realistic but way-easier particle systems.
2. Shockwaves are pretty easy. I downloaded a shockwave imagemap somewhere that can be put on a square and animated. It's easy and fun.
3. For a more earth-based explosion, you'd need to find some stock video of an explosion. Then, you can use it as a texture for a square object (point it at the camera) and with some hoping, tweaking, texture-composing and more hoping, you can get animated explosions into your animation. Also, this could be done with a movie-editer, but I don't have one and I'm not assuming you do either.
4. Re-enter photoshop - and enter a new level of tedium. You can map explosions into your movie as if they were for a still one frame at a time...
I'd heard ATMOS has hired a pyrotechnics team to film their own explosions they can use in movies and such.
Y'know, when I have some time, I might play around with this. Anyone know where I can get some decent stills/movies of explosions for free?
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