Emit Mode Types QuickStart

This page provides a step-by-step guide to understanding emitter types in Phoenix FD for Maya.

Introduction

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This tutorial covers the basic workflows for using emit modes in Phoenix FD for Maya. By the end of this process, you will gain an understanding of how to use multiple sources and emitter types to create complex simulations.

To follow this tutorial, you need the Phoenix FD for Maya plugin installed. This page is a companion to go along with the QuickStart video posted on our YouTube channel and available here:

 

 

Tutorial Assets

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To download the ending scene file for this tutorial, please click the button below.

 

Download Project Files

Tutorial Steps

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Create a new Maya file and make a sphere. Scale it up in the scene.

 

 

 

With the sphere still selected, click the Create Phoenix FD Fluid Simulator button in the Phoenix Shelf, and draw out the simulator grid around the sphere.

 

 

In the Grid rollout, adjust the simulator X / Y / Z Size to 188 x 150 x 188.

 

At the bottom of the Dynamics rollout, set the Steps Per Frame to 1.0.

 

 

Move the sphere up to the center of the simulator as shown below.

 

 

 

Create a source by clicking on the Fire/Smoke Source button in the Phoenix Shelf, and then click to place the object in the scene.

 

Select the sphere, and then Shift + Click the Fire/Smoke Source. Click the Add Selected Objects button (shown below) and select the sphere to add it as a Source.

 

 

 

Notice that the Emit Mode is set to Surface Force by default. This means that the surface of the emitter, the sphere, will be used to discharge fluid along its normals.

 

 

 

Set the Discharge to 5.0 and right click to Set Key at frame 50. On frame 51, change the value to 0.0 and Set Key. This will animate the discharge so it stays at a value of 5.0 from frame 0 to 50, then turns off at frame 51.

 

 

Start the simulation to see the particles emitting from the surface of the sphere. Stop the sim after the first few frames.

 

 

 

Select the simulator, open the Dynamics rollout, and turn Gravity to 0.0 to prevent the smoke from rising.

 

 

 

We only want to produce smoke for this simulation, so select the Fire/Smoke Source and turn off Temperature.

 

 

 

Start the simulation again, and notice that only Smoke is created on the sphere's surface. Stop the simulation.

 

 

 

 

Let's break up the regularity of the smoke with an animated mask. First, click the Clear Simulation Cache button from the Phoenix Shelf. Click Yes at the prompt.

 

 

 

Select the Fire Source and click the Create Render Node button for Smoke Map. Select Noise.

 

 

Select and right-click the sphere in the viewport. Select Assign New Material and choose a VRay Mtl.

 

 

 

Open the Hypershade and select the newly created VRayMtl node. Navigate to the Textures tab and middle mouse click and drag the Noise texture onto the VRayMtl Diffuse Color channel. Close the Hypershade.

 

 

Enable textures in the viewport by pressing 6 or clicking the Textured button shown below.

 

 

To animate the texture to slowly appear over time, go to frame 1 and select the Noise texture node. Set the Threshold to 5.0, the Amplitude to 6.0, Depth Max to 6, and the Frequency to 3.0. Set the Noise Type to Perlin Noise.

 

 

 

Right click and select Set Key for Time, at its default value of 0.0, and then also key the Threshold at its current value of 5. Then on frame 50, set Time to 1.0 and Threshold to a value of 0.5 .

 

 

Scrub the animation to see how the noise texture gradually appears over 50 frames. However, we need to reverse the colors. In the Color Balance rollout, set the default color to Black and enable Alpha is Luminance. In the Effects rollout, enable Invert.

 

 

 

The animated texture should look like the following images:

 

 

 

Start the simulation and then Stop it around Frame 30. The smoke production animates over time according to the animated noise texture on the sphere.

 

 

 

Select the simulation and go to the Preview rollout. In the GPU Shade Preview section, check Enable. To see the effects better, switch the viewport to Wireframe by pressing 4.

 

 

Let's add more smoke. Select the Fire Source and change the Smoke value to 2.0.

 

 

 

Select the Sphere Shape node in the Attribute Editor and locate the Extra Phoenix FD Attributes. Uncheck Solid to make it a non-solid object in the simulation. This will prevent the sphere from interacting with the other emitters we will create next.

 

 

In the Render Stats rollout, disable Casts Shadows, Primary Visibility, Visible in Reflections, and Visible in Refractions. This prevents the sphere from appearing in the final render.

 

 

Let's create a new sphere that uses a different emitter type. Press Ctrl + D to duplicate the sphere. Scale the new sphere down.

 

 

 

For better visibility, the object's display color can be changed. In the Object Display rollout, open the Drawing Overrides and click Enable Overrides. Select a new Color.

 

 

This second sphere needs its own Fire/Smoke Source, so we need to disconnect it from the existing one in the scene. Select the Fire/Smoke Source and click the Edit Object Set button to launch the Relationship Editor. On the left, select phxSource_set1 then deselect pSphere2 on the right.

 

 

From the Phoenix FD Shelf, create another Fire/Smoke Source in the scene. With the new Source selected, use the Edit Object Set button to add pSphere2 to phxSource_set2.

 

 

In the Source settings, change the Emit Mode to Volume Brush. This mode will fill the volume of the emitter object gradually over time as a percentage set by the Discharge(Brush Effect (%)) value, which we will animate later.

Note that the Volume Emit Modes require the emitter to be non-solid. If it isn't, Phoenix will prompt you to change it.

 

 

This sphere will fill up with Temperature only, so uncheck Smoke in the Source settings.

 

 

 

Next, we'll animate the Discharge. On frame 5, set the value to 60 and Set Key. On frame 34, Set Key at a value of 30.

On frame 35 and 50, Set Key to 60. Finally, on frame 51, Set Key at a value of 0.0.

 

 

Start the simulation. The second sphere is difficult to see, so while the sim runs, select the simulator. Open the Rendering rollout and open the Fire section.

Under the Fire rollout, select the lower point in the Color and Intensity graph to activate it. Change the X value to 600. This allows the heat to become visible sooner.

Set the Fire Multiplier to 2.0, and change Physically Based to 0.4. This reduces the Black-Body shader, which causes lower temperatures to be invisible and higher temperatures extremely bright. Overall, these adjustments will make the intensity of the fire easier to see.

 

 

 

Stop the sim sometime after Frame 50. Scrub the timeline to see the inner sphere gradually fill with fire.

 

 

Let's make a third sphere with a different emitter type. Go back to Frame 0 and select the inner sphere. Use Ctrl+ D to duplicate it, and then scale the third sphere down. Change it to a different color for better visibility using the Drawing Overrides as we did earlier in the tutorial.

 

 

First, remove the third sphere from phoenixSource_set2.

 

 

Then, create a third Fire Source and place it in the scene, and use the Edit Object Set button to add pSphere3 to phxSource_set3.

 

 

 

For this third Source, change the Emit Mode to Volume Inject. This mode uses the object's volume for the emission, but the fluid will discharge with added pressure.

 

 

 

Set the Discharge (Inject Power) to 0.0 and Set Key on frame 49 and 51. On frame 50, Set Key at a value of 2000. This will cause a quick burst for an explosion.

 

 

Not only can Inject Power be used to make an outward explosion, but a negative value can be assigned to create an implosion as well. Navigate to Frame 80 and set Discharge to 0.0 and Set Key. At Frame 81 set it to -5000 and Set Key.

With these keyframes, an explosion will occur at frame 50 and an implosion will follow starting on Frame 81.

 

 

Before running the simulation, select the sim and navigate to the Grid settings. Enable the Adaptive Grid by setting it to smoke Smoke. This expands the simulation grid in relation to the smoke. Lower the Threshold to 0.01 to increase the sensitivity for expanding the grid, and change Extra Margin to 20 in order to detect fast-moving fluids.

 

 

 

The simulation is already complete up to Frame 50, so to save on simulation time, go into the Simulation rollout and change the Start Frame to 50. Start the simulation.

 

 

 

Stop the simulation after a few frames have passed.

 

Frame 52

 

To add more swirls to the explosion, go to the simulation's Dynamics settings and increase Conservation Quality to 40. Higher Conservation Quality values create a stronger explosion shockwave, and enhance the implosion effect created with the negative Discharge value. With lower values, the implosion will not have enough power to draw in all the smoke.

 

 

 

Since the explosion is not influenced by gravity, we can make it look suitable for outer space. To change the look of this explosion, navigate to the Rendering rollout and open the the Fire rollout. In the Color and Intensity graph, double-click between the arrows of the left color to bring up the Color Picker. Change it to green (HSV around 100, 1.0, 0.7).

 

 

 

To make the fire appear hotter, we can increase the Fire Multiplier. If you set it to a value of 20, it might look a bit too much at the beginning of the explosion. In addition, the simulation will lose the gradual filling of the sphere. To fix this, we can animate this value.

To gradually increase of temperature in the green fire, go to Frame 50, change the Fire Multiplier to 2.0, and Set Key. Move to Frame 51 and set the value to 20, then Set Key.

 

 

Collapse the Fire rollout and expand the Smoke Color rollout. Move forward to Frame 53 and change the smoke Constant color by clicking the color swatch. For this example, we'll make the color a dark purple (HSV 250, 0.75, 0.25).

 

 

 

To add a light to the scene, click the V-Ray Sun button from the V-Ray Shelf. Move it up and to the left in the viewport.

 

 

 

In the Sun settings, set the intensity multiplier to 0.01.

 

 

 

Frame your shot, and select the simulation. In the Simulation rollout, change the Start Frame back to 0. Then in the Grid rollout, increase the simulation resolution by changing the Cell Size to 0.128. This brings the Total Cells to around 20 million.

 

 

 

Start the simulation. Here's a frame of the final simulation and its render.