Examples of using the Particle Sampler Info node
To help you use the Particle Sampler Info node we've included the following examples to help you learn how to use the Particle Sampler Info Node to achieve some commonly used effects. Refer to Set Particle Sampler Info node attributes on page 137 for complete information on Particle Sampler Info node attributes. Example Using the particles' age to color particles on page 129 Example Using the Particle Sampler Info node with rgbPP on page 131 Example Creating fading particle on page 133 Example...
Volume fields
You can select a volume to define the region in space in which particles or rigid bodies are affected by any field in Maya. The volume shapes you can use are cube, sphere, cylinder, cone, and torus. For example, if you create a Turbulence field and set its volume shape to cube, only particles or rigid bodies within the region of the cube are affected by the turbulence. This works with all fields in Maya, as well as with the Volume Axis field.
Work with perparticle field attributes
You can manipulate field attributes on a per-particle level. This functionality works for the case where particleShape is used as the source of the field, as well as the case where the particleShape is affected by a field. In the case where the attribute is affected by both, the value from the particleShape acting as the source of the field will take precedence. If the particleShape is acting as the source of the field, this feature allows each field to behave its own way. If the particleShape...
Shatter
Shatter duplicates an object and breaks the duplicate into multiple pieces called shards. Depending on the type of shard you choose to create, you can move the shards with dynamic forces or keyframe their movement. Shatter provides three methods of breaking the object Surface shatter Create shatter on page 336
Play back different caches
You can use particle disk caching to create different caches for the same scene. This lets you create and quickly play back variations on a scene. To create and play back different caches 2 Select Solvers gt Create Particle Disk Cache gt . 3 Enter a name for the Cache Directory or leave the default name, which is the scene name. 4 Click Create to create the cache. 5 Make any changes to your particles. 6 Select Solvers gt Create Particle Disk Cache gt . 7 Enter a new name for the Cache Directory...
Animate the particles
You can animate particle motion several ways You can animate particle motion several ways Set the position, velocity, or acceleration attributes of particles. You can also set keys to animate an entire particle object's translate, scale, and rotate attributes. See Choose how particles render on page 37 . Apply fields, such as gravity, to particles see Chapter 3, Fields . Turn geometry into a collision object and bounce particles off it see Particle collisions on page 23 . Make the particles...
Change the extrusion value of a shard
Once you've created a shatter with an extrusion, you can change the extrusion value for all the shards or for individual shards using the Local Translate Z attribute of the shard shape. If you haven't created the shatter using an extrusion, an extrusion node is not connected to the shards. To change the extrusion value of a shard 2 If the shard is a rigid body or a shape, In the Channel Box, select shardShape . 3 In the Channel Box under INPUTS, select polyExtrudeFacet . 4 Scroll down in the...
Combine rigid body dynamics and keys
When a rigid body is passive, you can animate it by keying its Translate and Rotate attributes. When the rigid body is active, you can animate it with dynamics, specifically fields and collisions. Sometimes you'll want to use a combination of keys and dynamics. For instance, you can roll a ball off a table with keys then cause the ball to fall with gravity. Motion from keys Motion from keys plus gravity. The ball retains the rolling motion it had immediately before control switched from keys to...
To use keys after dynamics
2 Make the object a rigid body and use dynamics to control its motion. 3 At the first frame where dynamics control the motion, select Soft Rigid Bodies gt Set Active Key. This keys the Active attribute to the on setting and keys the object's current Translate and Rotate attribute values. 4 At the first frame where you want the Translate and Rotate keys to have control, select Soft Rigid Bodies gt Set Passive Key. This keys the Active attribute to the off setting and keys the object's current...
To view hardware rendered particles from within Maya
1 In the Hardware Render Buffer, select the sequence of images you want to view from the Flipbooks menu. The hardware rendered particles are displayed in an Fcheck display window. See the online documentation for Fcheck. The play repeats continuously unless you specify otherwise with an fcheck option. You can specify Fcheck options. 2 To close the Fcheck display window, press Esc Windows, Linux, and IRIX or Command q Mac OS X . Notes Inadequate memory or processing speed might cause play to be...
Set field attributes with workspace manipulators
You can use manipulators in the workspace to edit the most commonly used attributes of fields. The manipulators offer an interactive alternative to typing entries in the Attribute Editor. To use a manipulator on an attribute 2 Select the Show Manipulator Tool from the Tool Box. Attribute manipulators appear next to the field icon see following figure . The manipulators show names and values for Magnitude, Attenuation, and Max Distance. Also displayed are curves and lines that graphically...
Sprite Wizard
The particle SpriteWizard simplifies the process for displaying a texture image or image sequences on particles. The particle Sprite Wizard leads you throughthe steps necessary to associate image files with sprites. You can assign a single image or a sequence of images to each particle. The images can be assigned randomly, or using various criteria such as the particleID or a ramp. You can also edit the sprites once you've created them with the Sprite Wizard. assigns a Lambert material to the...
Special Effects
Sets where the field emanates from the object. If you turn on Apply Per Vertex, each individual point CV, particle, vertex of the chosen object exerts the field equally at full strength. If you turn off Apply Per Vertex, the field is exerted only from the average position of the specified points. If you are using the Attribute Editor, open the Special Effects section to display the Apply Per Vertex attribute. Available for object fields only. Volume determines the region where the field affects...
Rigid bodies
A rigid body is a polygonal or NURBS surface converted to an unyielding shape. Unlike conventional surfaces, rigid bodies collide rather than pass through each other during animation. To animate rigid body motion, you use fields, keys, expressions, rigid body constraints, or collisions with particles. Rigid body collision created by Chris Ford Maya has two kinds of rigid bodies active and passive. An active rigid body reacts to dynamics fields, collisions, and springs not to keys. A passive...
Particles Goal
Reference gt Particles gt Instancer Replacement Particles gt Goal gt Here are the options you can set in the Goal Options dialog box. Goal Weight The goal weight sets how much all particles of the trailing object are attracted to the goal. You can set the goal weight before you create the goal using the Goal options window. You can set goal weight to a value between 0 and 1. A value of 0 means that the goal's position has no effect on the trailing particles. A value of 1 moves the trailing...
Setting goal weight on a per object basis
When you add a goal to an object, Maya adds a corresponding goal weight attribute to the trailing particle object. The goal weight sets how much all particles of the trailing object are attracted to the goal. You can set the goal weight before you create the goal using the Goal options window, or you can adjust the goal weight afterwards using the Attribute Editor. You can set goal weight to a value between 0 and 1. A value of 0 means that the goal's position has no effect on the trailing...
Particles Particle Tool 1
These are the descriptions of the items in the Particle Tool options window. The name helps you identify the object in the Outliner. If you don't enter a name, the particle object receives a default name such as particle1. Influences the motion of particles whose velocity and acceleration attributes are controlled by dynamic effects. See Conserve on page 183. Enter the number of particles you want to create per mouse click If you choose a number greater than 1 for Number of Particles, you can...
Add or remove springs after creation
After you create springs on an object, you can add or remove selected springs to tune the spring effect. This is useful if you need to add a few more springs to an object between points previously without springs. You can also add two springs to the same pair of points to increase rigidity. A single stiff spring has an attractive force that differs from two springs set less stiffly. The right object stretches less than the left because of increased spring rigidity that results from extra...
Get data on velocity forces and collisions
A rigid body has read-only attributes that contain its current velocity and any forces and collisions applied to it. This section describes these attributes. Force, velocity, spin, and torque attributes When you select a rigid body, the Attribute Editor shows the current X, Y, and Z component values for Velocity, Spin, Force, and Torque. You can also query these attributes in MEL commands or expressions by using the attribute names in the following table. This displays the contents of velocityX...
Rigid body constraints
Rigid body constraints restrict the motion of rigid bodies. The constraints simulate the behavior of real-world items you're familiar with pins, nails, barriers, hinges, and springs. You can constrain rigid bodies to a position in your scene or to other rigid bodies. If you create a constraint on an object, Maya automatically makes the object a rigid body. Rigid body constraints restrict the motion of the balls. This chapter describes how to work with rigid body constraints. For details on...
Specify where the cache files are stored
Maya has a workspace directory for particles. By default, this is given the name particles. You can specify your workspace particles directory using the Project Editor, the same as for all the other workspace directories. If you are using an old workspace from a previous version of Maya, Maya creates the particles directory for you the first time you create a particle disk cache. The disk cache files are stored in subdirectories of the particles directory. You can specify what subdirectory name...
Particles Make Collide
Makes particles collide with geometry. Particles gt Make Collide gt Here are the options you can set in the Collisions Options dialog box. Resilience Sets how much rebound occurs. A value of 0 makes particles collide with no bounce. A value of 1 causes particles to rebound fully. A value between 0 and -1 makes the particles pass through the surface with refraction out the back side. Values greater than 1 or less than -1 add speed to the particles. Sets how much the colliding particle's velocity...
Dynamic attributes
Dynamic attributes have predefined names and purposes. Maya adds dynamic attributes to the particle object in response to your user interface selections. An object has no dynamic attributes unless your actions cause Maya to add them to the object. You can set per object and per particle opacity and color of a particle object. The procedures require you to add dynamic per particle or per object attributes for the opacity and color. See Per particle and per object attributes on page 36 for...
Particles Create Emitter
Particles gt Create Emitter gt This sets the options when you create an emitter. Basic Emitter Attributes Emitter type Select one of these choices from the pop-up menu Omni Sets the emitter type to an omnidirectional point emitter. Particles emit in all directions. Directional Sets the emitter type to a directional point emitter. Particles emit in the direction you specify with the Direction X, Y, and Z attributes. Surface Emits particles from randomly distributed positions on or near a NURBS...
Creation Method
MinMax Creates springs only within the range of Min and Max Distance options. You can use the MinMax option to cause selected particles to adhere to each other, for example, to simulate a puddle of fluid. All Creates springs between all pairs of selected points. Choose this option when you want an object to have a uniform spring structure throughout its shape, for example, a bouncing ball or block. Wireframe Creates springs between all particles on the outer edges of a soft body. This option is...
To tune goal weight animation
1 Select the trailing particle object. 2 Display the Attribute Editor and open the Goal Weights and Objects section. 3 Set the Goal Smoothness to a value of 1 or greater, as follows With a Goal Smoothness of 1, the goal weight effect increases proportionally as goal weight rises in small increments from 0 to 1. For higher values of Goal Smoothness, the goal weight effect increases slowly as values rise above 0, and quickly as the values approach 1. Objects have a default Goal Smoothness of 3....
Create a Particle Sampler Info node
This is the general procedure for creating a Particle Sampler Info node. These are general steps we've included examples of specific tasks in Examples of using the Particle Sampler Info node on page 128. To create a Particle Sampler Info node 1 Create your particles and set the Render Type Cloud, Blobby, or Tube. 2 Determine which particle attribute you want to use to drive a shader attribute. 3 Add that attribute to the particle shape, if necessary. 4 Select the particles and display the...
Display Label
Labels rigid bodies as active or passive. Also shows the type of constraint. Turn on Display Label to see active and passive rigid bodies labeled in the workspace. Constraint types are also listed. This node contains the attributes for the rigid constraints. These constraints can only be used with rigid bodies. The constraints include nail, pin, hinge, spring, and barrier.
To create springs within an object or between two objects
1 Select the objects or components to which you want to add springs. 2 Select Soft Rigid Bodies gt Create Springs gt to display the Spring options window. 3 Set options as described on Set spring attributes on page 278. Tips If you use springs on a polygonal soft body or a NURBS soft body with many vertices and particles , you can improve playback efficiency and spring response by putting springs on a simplified proxy object. See page 289. To cancel spring creation after you click Create, press...
Sprite attributes 1
Specifies how images are assigned to the sprites. Select one of the following off - Each particle uses some fixed image throughout its lifetime. on - Each particle displays a sequence of images in turn. Selects the technique used to assign the initial sprite to each particle. Select one of the following first - Every particle uses the first image in the sequence. particleid - The particle uses its particleld value to pick an image. If the particleId is greater than the number of images in the...
Set particle attributes with a ramp texture
A ramp texture is a 2D texture in which the color or grayscale value changes from one value to another across the extent of the image. You can use a ramp to control per particle attributes as particles age. You can also connect a ramp texture to any other per particle attribute of the particle. You commonly use ramp textures with the rgbPP, opacityPP, and radiusPP attributes. For most per particle attributes, you must add the attribute to the particle object before you use the ramp to control...
Key and parent constraints
You can parent the following constraints or key their positions This nail constraint's Translate X attribute is keyed with an increasing This nail constraint's Translate X attribute is keyed with an increasing value. Gravity pulls the ball down. The result is a swinging ball moving through space. value. Gravity pulls the ball down. The result is a swinging ball moving through space.
General Control Attributes
A value of true toggles dynamics on for the object. A value of false toggles dynamics off for the object. A value of 0 causes fields, collisions, springs, and goals connected to the particle object to have no effect. A value of 1 provides the full effect. A value less than 1 sets a proportional effect. For example, 0.6 scales the effect to 60 of full strength. Expressions are unaffected by Dynamics Weight. The Conserve value controls how much of a particle object's velocity is retained from...
To use a ramp to color particles according to their distance from origin
1 Create a sphere volume emitter. Set the Volume Speed attributes as follows Away From Center to 1 all the other speeds to 0. Set Scale 10, 10, 10 . To do this, you can copy the following Mel commands from the online help and paste them into the Script Editor emitter -pos 0 0 0 -type volume -r 100 -sro 0 -nuv 0 -cye none -cyi 1 -spd 1 -srn 0 -nsp 1 -tsp 0 -mxd 0 -mnd 0 -dx 1 -dy 0 -dz 0 -sp 0 -vsh sphere -vof 0 0 0 -vsw 360 -tsr 0.5 -afc 1 -afx 1 -arx 0 -alx 0 -rnd 0 -drs 0 -ssz 0...
Edit general Fireworks attributes
After you create the fireworks, you can adjust general, group-related attributes by editing the fireworks attributes. You can do this using the Channel Box or the Attribute Editor. Start by selecting the fireworks group selection handle. Selection handle for fireworks group Affects how fast all rockets burst, and, consequently, how wide the bursts appear. Each particle in the burst has a random speed, and this speed is the maximum. Each burst consists of a number of streaks randomly distributed...
Springs
You can add springs to a soft body's particles to give the soft body internal structure and improve your deformation control. You can also add springs to regular particles to give them reactive, interconnected motion. The number of springs and their stiffness alters the effect of the springs. Springs on the soft body cube cause it to flex when it collides with the floor. You can create springs between particles and CVs or vertices of soft bodies vertices of polygonal objects At least one of the...
Connect flows on separate surfaces
You can connect flows from separate surfaces so they share the same particles. The workflow is different depending on whether you create flows at the same time or start with an existing flow. 1 Select the surfaces in the order you want the particles to flow. 2 Choose Effects gt Create Surface Flow gt . 3 In the options window, turn off Create Particles Per Flow. 4 In the Control Resolution option, specify the number of flow manipulators per surface. The effect creates one flow per surface, with...
Edit attributes of the Smoke effect
The following pages explain attributes for tuning the Smoke effect. The Smoke effect creates several custom attributes in the emitted particle object it creates. The custom attributes control a combination of field and emitter attributes to lessen the settings you would otherwise need to make to tune the smoke. Attributes in the Create Smoke Effect Options window The following attributes appear in the Create Smoke Effect Options window when you select Effects gt Create Smoke gt . Changes you...
Numeric
The Numeric render type displays the current values of any attribute of the particle object. This is useful when you want to know the value of an attribute such as velocity at a certain frame. By default, Maya displays particle ids for the Numeric render type. 2 In the Attribute Editor, set Particle Render Type to Numeric. 3 To add default Particle Render Type attributes, which let you tune the appearance, click the Add Attributes For Current Render Type button.
To connect a particle object to a single goal object
1 Select the particle object you want to be affected by the goal. To select a soft body rather than a conventional particle object, you can select the soft body's original geometry or its child particle object. 2 Shift-select the object you want to become the goal. 4 To adjust the goal's influence, see Edit goal attributes on page 108. 5 Play the animation to see the particles move towards the goal. Note To make particles follow the object's transform rather than its particles, CVs, vertices,...
Create fields and connect objects to them
When you create a field, you typically also connect it to the objects you want the field to influence. You can alternatively connect objects to the field's influence after creation see Chapter 8, Dynamic Relationships Editor . As long as a connected object lies within the influence of the field, it will be affected by the field. Although each field has a different effect, the technique for creating all fields is similar. For information on the effect of each field and how to adjust those...
Static attributes
Static attributes are attributes the particle object has by default. For example, a particle object's transform node has the static attributes Translate X, Rotate Y, Scale Z, and so on. A particle object's shape node has many static attributes that are listed in the Particle Attributes section of the Attribute Editor. You can set the values of these attributes with the Attribute Editor, expressions, and other techniques after you create the object. The values you specify for static attributes...
To ensure ramp colors portray attribute values meaningfully
1 Set the lowest RGB or R values in the ramp to 0, and set the highest RGB or R values in the ramp to 1. 2 Right-click the attribute box of the per particle attribute that's connected to a ramp, slide the pointer to the arrow to the right, and select Edit Array Mapper. The array mapper lets you scale the range of attribute values applied to the particles. 3 Click the array mapper tab of the Attribute Editor. 4 For the Min Value and Max Value, enter the lowest and highest values you want to use...
Fields Volume Axis
Specifies the strength of the volume axis field. Sets how much the strength of the field diminishes from the central axis of the volume axis field. If you set Attenuation to 1, the strength of the field diminishes in a linear manner from full strength at the central axis to zero strength at the edge of the volume axis field. Values greater than 1 make the strength of the field diminish to zero in an exponential manner the greater the value, the more rapidly the strength decreases. A value of 0...
Create soft bodies
NURBS curves and surfaces, including curves for IK splines and wires anything in the underworld of a shape, such as a curve-on-surface trimmed NURBS surfaces, unless you convert them to polygons first Tips The more CVs or vertices the original geometry has, the more deformations that occur when you apply dynamics to the resulting soft body. For instance, applying a field to a polygonal cube with eight vertices per face causes less bulge and wiggle than one with 16 vertices per face.
Edit attributes of the Fire effect
The following pages explain attributes you can set to tune the Fire effect. The Fire effect creates several custom attributes in the emitted particle object it creates. The custom attributes control a combination of field or emitter attributes to lessen the settings you would otherwise need to make to tune the fire. Attributes in the Create Fire Effect Options window These attributes appear in the Create Fire Effect Options window when you select Effects gt Create Fire gt . Changes you make to...
Edit field attributes
The type of field and its attributes specify the kind of effect it has. You can set the field attributes before you create the field, or you can create a default field and set the attributes after creation. To set field attributes before creating the field 1 Select Fields gt fieldname gt to display the options window for the field. To enter a value that exceeds a default slider range, type the value in the text box. 3 Click the Create to create the field. To edit field attributes after creating...
Recreate the cache
Once you have created the cache, Maya uses that cache until you tell it not to. It ignores any changes in emission, forces, etc. on that particle object. If you change something in the scene that alters per-particle attributes, you must re-create your cache in order to get correct renders. Maya writes out the disk cache only when you select Create Particle Disk Cache. That menu item does not turn on a caching state. This is an important difference between memory caching and disk caching. Maya...
Use particle disk caching Create a particle disk cache
After you have created a particle disk cache, Maya uses the cached particle data, no matter what changes you make to your scene, until you explicitly tell it not to. For example, if you cache the scene, then apply a gravity field to a particle object, you will not see any effect from that field because Maya is using the cached particle motion. To see the effect, you must turn off Use Particle Disk Cache see Editing particle disk cache settings on page 380 . However, if you make a change that...
To connect a particle object to multiple goal objects
1 Select the particle object or soft body you want to be affected by the goals. 2 In the workspace, shift-select one of the objects you want to become a goal. 4 Deselect all objects and repeat the previous steps for the next object you want to become a goal. 5 To adjust the goal's influence, see Edit goal attributes on page 108. 6 Play the animation to see the particles move towards the goal.