Particle Explosion Part 2 - Hot Balls of Fire
Tutorials in this series:
- Particle Explosion Part 1 - The Explosion: Create a fiery explosion particle for multiple purposes, including an FX sequence.
- Particle Explosion Part 2 - Hot Balls of Fire: Create a ball of fire that will be emitted with it's own smoke trail for use in a FX.
- Particle Explosion Part 3 - Adding Debris: Create some debris that will be emitted to accent the explosion.
Particle Explosion Part 2 - Hotballs of Fire
In this tutorial we are going to use the explosion we created in part 1 and give it its own smoke trail for use in later FX. This tutorial assumes you have a working knowledge of the creating paths and followers.
Step 1 - Create or Select a Texture
We already did this in the first part of the series. Make sure you are in the same area where you made the first explosion particle, and that you have an instance of it created in the area.
Step 2 - Make a Path
Make a path, since this particle will be leaving particles behind to create a smoke trail behind it, the easiest thing to do is parent an instance of it to a path follower so that it can have constant motion while testing. Take some time now to build a moderate sized circular path with a follower on it.
Step 3 - Create an instance of Explosion_Tutorial_01
Now we will create a local particle spec with HeroEngine. From the create menu, go Create/Particle/Explosion_Tutorial_01.
Step 4 - Parent the new instance of the Particle Spec
Keep 1 instance off to the side, and parent the other one to the follower you created on the path. Then set the End_Behavior of the follower to "Go_to_First_Waypoint" and unpause the follower(set Pause to False).
Step 5 - Tweak Properties
Select the instance of Explosion_Tutorial_01 that isn't attached to the follower. Now we'll edit the particle to look like a trail:
on the emitter tab
1 - Change the EmitFrequency to 0.001
on the particle tab:
2 - Change the Scale
- Change both the XScale2D and the YScale2D to .15
- Change the Size2D to a Timeline via the option dialog and alter it to look like the following.
3 - Change the DiffuseColor to a color timeline like in fig 1
4 - Change the blending modes
- SourceBlend to BOTHSRCALPHA
- DestBlend to ONE
Step 6 - Create a Second Emitter
1 - Create an emitter through the create menu, and we only want the emitter, so uncheck "create particle". Call this new emitter ExplosionMain. This emitter will emit the "Explosion_Tutorial_01" emitter. So we will have an emitter emitting an emitter that emits a particle. That might sound confusing if you've never worked with particles before, but we are now going to have ExplosionMain firing out Explosion_Tutorial_01, which will then be firing out the textures of the explosion.
2 - Select the Explosion_Tutorial_01 emitter and select the spec from its Name property under the Type section. Hit ctrl c to copy the entire path for Explosion_Tutorial_01
3 - Now select ExplosionMain, and paste that path your just copied for Explosion_Tutorial_01 into the 'EmitSpec' property of the emission section for ExplosionMain
4 - You may need to reselect ExplosionMain to see the properties window update with all the new tabs. Previously when selecting an emitter you would see a tab for the emitter and for the particle, now you will see a tab for the first emitter, and the second emitter, and the particle.
Step 7 - Tweak Second Emitter
Now we're going to adjust this new particle chain. If for some reason you don't have an instance of ExplosionMain in your area, create one now, and select it.
Select the tab for Explosion_Tutorial_01 emitter (it should be the second tab from the right). We are going to set the motion attributes of this emitter so that is creates trails of flame like you would see in an explosion. In a normal particle chain, where there is only 1 emitter and 1 particle, the motion section is not used on the emitter. Sine this emitter is being emitted by another emitter, we use these motion properties to control the motion.
1 - Set Lifespan to 4
2 - Set Buoyancy to .25
3 - Set the trajectory to have a Gaussian value on each axis, but lets have it it be more vertical then horizontal.
- On Y do a min and max of.3 and 1
- On X and Z do a min and max -.6 and .6
Now select the tab for ExplosionMain: we need to adjust the emission attributes so that the secondary emitter, Explosion_Tutorial_01, emits properly from ExplosionMain. In this case we only want a few to be born, so under emission section:
1 - Set EmitFrequency to 10
- This only emits every 10 seconds, we want a burst not constant emission.
2 - Set NumberToEmit to 5
- We will emit 5 all at once, which should all go in separate directions since we have set the trajectory to be mostly random.
The resulting motion should be an arc for each emitter(seen below). The trajectory sends each emitter up and out and the Bouyancy will bring it back down to the ground. Make any needed adjustments for the look and feel of your explosion streaks. The other instances of the particle are still available for testing the particle itself, both the static one and the one on a path. This gives you a few options for selecting and editing the particle chain.