Monday, September 23, 2013


 UDK Explosion

Explosion! Bandicam likes to saturate colors

Textures - More

The textures I used could be seen in my previous post as well as more information on their creation. I used the red channel to save the temperature information, green for density, blue for the unmated alpha's, and the alpha channel for a dark to light radial filled "heat".
The combined texture ended up looking like this but with the above heat used in the alpha channel. The P-Mask created can be seen below.
Combined Texture (P-Mask) - What a mess


The shader was pretty large with around 50 instructions being done in the pixel shader but could be broken down into four portions Temperature, Density, Heat, and Opacity. Each portion primarily uses the channel in the texture provided for it with the opacity also taking advantage of the density channel. Macro-UVs were also used in the density and temperature in order to give off a little bit of that varying detail you can see when the explosion is slowed down.

Particle Animation

The explosion animation has five parts. Three are explosions happening in different directions with slightly different colors to give a little bit of variation and growth. I used a Dynamic Parameter with a uniform value in each of the explosion portions to give the shader even more variations in temperature, density, etc.

It also includes little flying chunks given an initial velocity and a negative velocity over time. The same method was used on the sparks however the sparks grow in the direction of their velocity. Also the sparks use a dynamically generated texture created in its own shader.

Thursday, September 19, 2013

Starting An Explosion

Maya Fluids Texture Generation

I've begun to use Maya Fluids to generate textures for an explosion. A volume axis field helped spread the fluid out in a spherical way, however, it was the temperature and turbulence that really made the explosion fluid explode.  It's also a good idea to remember to set the temperature buoyancy to zero or else your explosion will gravitate upwards.

I used after effects to control the growth and position of the explosion in order to make it look as if the explosion doesn't grow it all. This way I get to control the rate of it's growth in cascade (as individual particles) rather than have a texture with mostly unused space.

The explosion's density and temperature were rendered separately and can be seen below.



Tuesday, September 17, 2013

Burn The House Down - More Maya Fluids Practice

I made a burning house.

I made a house with different fire effects utilizing different techniques (with the help of digital tutors). There are a total of five fluid containers in this scene. This time the fires are temperature and fuel driven. I didn't make a video since rendering all this would have taken at least 15 hours on my current PC. Again, the goal wasn't to make a complete scene but to better understand Maya Dynamics so the fire colors don't match and the lighting is off.
The Burning House

The Front Door

The fire created for the front door is standard incandescence with a modified opacity graph. There is a rectangular emitter underneath the door. I only now realize it should have pushed further to theto the right along the x-axis.
Front Door Fire

The Overhang Fire

This piece is was done in a similar fashion to the front door fire however isn't as turbulent or hot. The piece of wood was also used as an emitter. A final volume axis field makes it appear as if it were being pushed around.
Porch Overhang Fire Close Up

Falling Fire Debris

I learned how to use Maya Particles as a fluid emitter here. The opacity graph really mattered here. Since I wanted the fluid to have more of a trail like effect more tinkering with the incandescence bias and  opacity was required. Although I wasn't to happy with the end result. They look too globular and am not too sure how to fix that yet.
Fire Debris Falling

Window Smoke

Density driven smoke. It also oscillates emission strength to give it that nice puffy feeling that smoke has. A directed volume axis field also made it puff away from the building without having to add a collider to the building wall.
Window Smoke

Fire and Smoke Blend

This one had fire and smoke being pushed out the same emitter and in the same container. This ended up working very similarly to the way real fire works. The incandescence dissipation (heat) essentially controlled where the fire would turn to smoke. There the density driven color shader would color the smoke. With the heat dissipated it would also then change the amount of energy in the fire producing slower heavier puffs. A volume axis field was again used to push the fire and smoke away from the building.
Window Fire

Thursday, September 12, 2013

Fluid Effects - Fire and Smoke with Particle Sparks


I made some fire and smoke using a digital tutors tutorial. A 2D fluid container was used for both. Overall I learned a lot and am happy with the results. I didn't pay much attention to the render details since my goal was to just learn about fluids. The tutorial also covered Maya Particles. So I learned how to make some sparks as well. The background was provided by the tutorial.


The fire is density driven. Density driven fire means that I'm not actually using the fluid fuel to generate Maya fire (and incandescence). Instead I'm using the shader attributes to modify the fluid color based on the density of the fluid. Combined with the opacity graph you could make very convincing fire. Finally uniform field can really make the fire look as if it's being blown violently by the wind.


The smoke is done in a similar manner but the density gradient force is positive instead of negative. Fire naturally appears to repel itself but smoke kinda clumps together. So it makes sense for the gradient force for smoke to be positive. Also turbulence and turbulence details go a long way.