This document provides a simplified tutorial for creating a massive explosion effect in Blender. It describes using the displace modifier on raw mesh objects to simulate the shockwave, rising hot gases, and fireball of a nuclear explosion. Texture animations controlled by empty objects are used to displace the meshes and simulate the rolling effect of warm gases. Materials with multiple textures reacting to animated lamps inside the fireball create the burning effect. Halos are added using spots parented to the fireball and sized by IPO curves.

1. Simplified tutorial: Massive explosion - Blender
Atomic bomb with Blender!
New version!
Previous version:
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2. Simplified tutorial: Massive explosion - Blender
Introduction
This article was created for people who are interested in creating virtual special
effects with blender.
This is the 2nd tutorial I wrote about this subject. This one has been simplified.
Anyway, it requires some basis with blender…
Global method
This technique I developed to simulate a massive explosion mainly uses the
displace modifier:
Raw meshes objects (without displacement)
Fireball
ColumnTop
Column
Shockwave
Meshes objects (with displacement and subsurf level 4)
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3. Simplified tutorial: Massive explosion - Blender
Massive explosion smoke dynamics
This picture shows the global dynamic of gazes produced by nuclear fission:
Warm burning gases rises and cool down with the altitude, which creates this
rolling effect on the fireball
To simulate this, we’ll use 3 empty’s which will be uses for displaced texture’s
coords.
« Empty’s » for texture’s animations
« Up »
« Fix »
« Down »
Adjust their size to obtain the best looking result when the modifiers have been
added (see below)
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4. Simplified tutorial: Massive explosion - Blender
IPOs: « Up » « Down »
Textures used for displacement
“Displ 1”
Large noise, this texture will be used to change the global aspect of each
mesh objects.
“Displ 2”
“Displ 3”
Small noise, for more details…
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5. Simplified tutorial: Massive explosion - Blender
Meshes: Shockwave
Animation
IPO keys (scale): Frame 100 : X,Y,Z = 0.0
Frame 500 : X, Y = 2.0 ; Z = 1.5
The shape of the curves are important, it
will give the damping effect : Quick
growth at the begining, then slowing
down
Note : Shockwave grew less in height
than in width
Modifiers
Subsurf : Here you can change the level
of details.
High values will increase the render time
1st deformation level:
Make the global shape of the object
changes
2nd deformation level:
More detailed. I used vertex groups to
randomize the displacement level over
the object’s surface.
3rd deformation level:
Also use of vertex groups
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6. Simplified tutorial: Massive explosion - Blender
Mesh : Column
Animation
IPO keys (scale) : Frame 100 : X,Y,Z = 0.0
Frame 500 : X,Y,Z = 1.2
Curve of Z axis is different. You’ll need to
adjust it depending of the rising speed
of the fireball object
Modifiers
This will give the sensation that hot gases
are rising up…
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7. Simplified tutorial: Massive explosion - Blender
Mesh : ColumnTop
Animation
IPO keys (scale) : Frame 100 : X,Y,Z = 0.0
Frame 500 : X,Y,Z = 1.5
IPO keys (loc) : Frame 100 : Z = 0.0
Frame 500 : Z= 10.0
Z loc, to make the object rising
Modifiers
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8. Simplified tutorial: Massive explosion - Blender
Mesh : Fireball
Animation
IPO keys (scale) : Same than the previous object
IPO keys (loc) : Same than the previous object
Same IPO block than the ColumnTop
object
Modifiers
Important : For the « rolling » gases effect
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9. Simplified tutorial: Massive explosion - Blender
Materials :
Here we are going to see how to create the burning in the core of the fireball.
For this we’ll use 4 times ONE texture which will react to the lighting of 4 lamps.
Each texture will be linked to one lamp.
Creating the 4 lamps
Add 4 lamps (renamed to “FireBallL 1,2,3,4”) and linked them to the object
fireball (parent)
Place the lamps randomly in the
fireball.
Lamp settings:
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10. Simplified tutorial: Massive explosion - Blender
Add an IPO curve for th lamp’s power
(combustion attenuates)
Material
It will be used for shockwave, column, columnTop and fireball (actually, every
objects…)
Texture
Assign 4 times this texture to the material (in 4 different channels)
Every texture will have a linked lamp :
Tex in channel 1: FIreBallL1, Tex in channel 1: FireBallL2, Tex in channel 1:
FireBallL3, Tex in channel 1: FireBallL4
Activate « Emit » and « TransLu ».
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11. Simplified tutorial: Massive explosion - Blender
Halos
First, put the 3d cursor on the fireball. Then add 4 spots.
For each one, add a constraint “track to”, to direct them to the active
camera:
The glare comes mainly from the fireball, this is why the spots must be parented
to the object “fireball”.
Spots settings
Add an IPO curve the control the spot size (for the attenuation)
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12. Simplified tutorial: Massive explosion - Blender
Conclusion
Thanks for following this tutorial! I hope it was useful.
Visit my web site http://www.fweibel.com
My youtube channel: http://www.youtube.com/faweil
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