Create 3D animated fireworks in rFactor2 (Guide + Free Assets)

svictor

svictor

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As we know, RF2 normally doesn't support modding real particle animation. This is a prove of concept for creating 3D particle animation and effects for RF2.

This implementation utilizes RF2's new IBL shader and texture animation to emulate dynamic 3D fireworks animation.

The first implemented example of this method can be experienced in Dundrod 1955 mod.

2025-08-21 19-47-21.jpg


Basic Concept:
The main idea is to create a bunch of 3D strips, radiating outward to form a sphere-like fireball. Then, create a fire particle texture, which will be animated using "scrolling animation" to move the particle texture along the 3D strip, emulating fire particle explosion trajectory.

For explosion type & speed randomization, this can be done by adjusting the rate of "scrolling animation" and UV map scaling, and also combining multiple different fire particle textures into one bigger texture.

For color randomization, this can be done by using IBL standard blending shader, applying an "overlay" color texture map on top of fire particle texture, and set this overlay map with random moving animation via "scrolling animation", effectively result random fireworks color.

For explosion position randomization, this can be done by using RF2's object rotating animation, see official guide here: https://docs.studio-397.com/display/DG/Object+Rotation+Animation

Finally, the 3D fireworks implementation currently used in "Dundrod 1955" mod utilized all above techniques to create dynamic and random looking fireworks.

Example file:
To make life easier, I have prepared some ready-to-use 3D fireworks files in attachment, which can be directly added to RF2 track with minimum efforts. Feel free to use those files in various RF2 track mods as you like.

The full tutorial for 3D fireworks creation in RF2 continues in following posts.

Good luck!
 

Attachments

Part 1 - Creating 3D fireball model in Blender

Note, basic blender usage is not covered here. This part is meant to share basic idea of how fireworks models are constructed, there can be different ways to create similar 3D models for fireworks.

1. "Add" a new "Bezier" curve object, rename it to "fireball". Then adjust curve control points (nodes) to emulate particle travel path.
t01.png


2. Rotate the "fireball" curve object so it aligns to "X viewpoint".

3. In object "Data" panel, set curve "Shape" to "3D", "Resolution Preview U" to "5", "Geometry Extrude" to "0.05 m".

4. Select curve's end node, then select "Control Points" > "Tile", and set "Tilt Angle" to "45" degrees. This step is meant for adding some rotation to particle moving path for more varied visual effect.
t02.png


5. "Add" two "Empty" "Plain Axes" objects, which will be used for "array modifier". Name the first "Plain Axes" object as "x_rot", and the second as "z_rot". Press "N" to open "Transform" panel, select "x_rot" object, set "Rotation X" to "10" degrees. Then select "z_rot" object, set "Rotation Z" to "-45" degrees.
t03.png


6. Select the "fireball" curve object, from "Object" menu, select "Convert" > "Mesh". Open "Modifiers" panel, add two "Array" modifiers, uncheck "Relative Offset", then check "Object Offset", set "Count" to "16" and "Object" to "x_rot" for first array. Set "Count" to "8" and "Object" to "z_rot" for second array. And it will now looks like a "ball" with many branches.
t04.png


7. Next (optional), select the "fireball" object, and enter "Edit" mode, then select some branches, and scale them bigger or smaller, which will make particle movement more random later on.

8. Open "Modifiers" panel, and apply the two "Array" modifiers on the "fireball" object.
t05.png


9. Add a new material to the "fireball" object, name it as "fireball01" (the numeric suffix is necessary, as we need more different copies later on), and assign texture to it (such as "fireball_Alba.tga"). UV map will be auto-created by blender (no need to remap UV map in this case).
t06.png


10. Now scale "fireball" object to around 40 to 50 meters width (in RF2's scale, which equals to 0.4 to 0.5 in blender), depends on how big the explosion you would like. In this case, I scaled it to around 50 meters diameter. Place the "fireball" object 20 to 70 meters above road or terrain surface (measure from center of ball), depends on how high the explosion you would like. In this case, I placed it 50 meters above road.
t07.png


11. Export the "fireball" object to "GMT" file in your track mod folder, and rename it with numeric suffix, such as "fireball_001.gmt", as later on you probably want to add many copies to create fireworks clusters.
 
Part 2 - Create fire particle, emissive, color overlay textures in GIMP

In this example, I setup a texture with a size of 8196 x 64 pixels, which holds two different types of fire particles: one with fire trail (long tail), one without.

Fire particle texture

1. Create a 8196 x 64 texture, then zoom in, move view to left canvas edge, paint a drop-like shape particle with grey color (#AAAAAA in this case). Note, the color of the particle will affect the brightness of fireworks. Below pic shows how the shape looks like with alpha channel set to hidden.

2. Move the view to the center of canvas, and draw another drop-like shape particle with significantly longer tail, this will be used as the second type of fire particle.

3. Export the file as fireball_Alba.tga.

m01.png



Emissive map

This texture will be used to control particle fade out effect. It will be a simply linear gradient texture from white to black.

1. Create a 2048 x 32 texture, then use Gradient tool to fill gradient color from white to black, as below.

2. Export the file as fireball_Em.tga.

m02.png



Color overlay map

This texture will be used to apply random color on top of fire particle texture to achieve random color explosion.

1. Create a 1024 x 1024 texture, then paint random color on it. There are many ways to do that, such as using "Filters > Render > Noise > Plasma". You may also want to limit the range of color, so some unusual color will not be included.

2. Apply "Filters > Blur > Gaussian Blur" to smooth out transition, and apply "Filters > Map > Tile Seamless".

3. Export the file as fireball_Ova.tga.

m03.png



Finally, use RF2's MapConverter to properly convert all TGA to DDS.
 
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Part 3 - Setup SCN file and material JSON

SCN file setup

In SCN file, add following lines:

Code: 
Instance=fireball_001
{
  VisGroups=(1024)  // show only in night
  MeshFile=fireball_001.gmt CollTarget=False HATTarget=False
}


Material JSON setup

For material JSON, we will use IBL standard blending shader:

1. Set shader to "L2IBLSTANDARDBLEND".

2. Set "Albedo Function" to "Multiply", "A UV" to "UV_A", Animate to "UVW_Scroll". "B UV" to "UV_B", "Animate" to "UVW_Scroll".
s01.png


3. Set "Emissive" function to "Night", "Use Map Mask" to "Mask_RG", "UV" to "UV_A". Then make sure "Emissive Scalar" value is set to "5000" (or higher, which affects brightness of the fire particle).
s03a.png


4. Under "UV_Scale", set Albedo "U scale" to "0.24", this value affects the length of fire particle and fire interval. Keep "V scale" as 1. Then set Emissive "U scale" to "0.99", this is done to avoid texture edge bleeding.

5. Under "UV_Animate", set "U rate" to a negative value, such as -0.0875. This value controls fire particle moving speed. Then set "V rate" to 0, as we don't want the particle to move vertically on the 3D strip.

6. Under "AlbedoAlt", set rate to any random value you like, this value controls how fast random color changes with each explosion, which this value should be kept quite low.
s02.png


7. Assign textures to each map channel, and make sure "Chroma Transparency" is checked for "albedoMap" channel, then save the material.
s03.png


8. Go to your material folder, open material JSON with notepad, then add "CUBEMAT_TWOSIDED" to "flags" section, such as below:
Code: 
  "flags":[
    "CUBEMAT_SPECULAR",
    "CUBEMAT_TWOSIDED",
    "CUBEMAT_AMBIENTMAT",
    "CUBEMAT_DIFFUSEMAT",
    "CUBEMAT_SPECLARDIR",
    "CUBEMAT_EMISSIVMAT",
    "CUBEMAT_EMISSIVDIR"
  ],

This step is most important to make sure fireworks can be viewed at any direction.

Finally, reload the track in DEV mode, the fireworks should be playing now.

To create a cluster of fireworks:

Copy the fireball GMT and material JSON files, name them with unique numeric suffix, such as fireball_001.gmt, fireball_002.gmt, fireball_003.gmt ... FIREBALL01.json, FIREBALL02.json, FIREBALL03.json ...

Then, open each GMT file and assign new material name that matches JSON file name. And individually adjust "UV_Scale", "UV_Animate", "AlbedoAlt" values as from step 4 to 6 for each different fireball copy. This way the fireworks cluster will be fully randomized when playing.
(just make sure that each fireball uses its own unique material with unique animation setting in a single fireworks cluster, so animations are played randomly without same repetition)

That's all.
 
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Many thanks S.Victor for this great game update, i will install it and try it out today. Great research and program knowledge.
 
I hadn't seen this message.
I think it's a very interesting idea and project. I really like these kinds of things.
It's a shame you can't use a trigger (for example, the one that is triggered when the first driver crosses the finish line and wins a race).
I'm editing a new circuit and I'm going to try it out.
Without having seen it, I give it a 10.
Thank you for developing these kinds of ideas.
 
Thanks.

I think a trigger to show firework only after leader crossed finish line is possible, such as by using one of those "CornerWorker" animation, where those CornerWorker 3D models (ex. flags) are hidden below ground, and only shows/moves above ground after race finished. Unfortunately that would still require of using commercial software (3dsmax) to generate required ANM file, which is not accessible for those working with opensource software like blender.
 
I completely agree with everything you say. I was thinking about starterworkers when I made that comment.
It would also have been nice if the same trigger could activate audio effects.
It's a shame there isn't a Blender plugin for exporting animations to rFactor.
Thank you for your contributions.
 
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