Particle Systems Lecture Notes 1
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Make a new project and call it ParticleExercises (use defaults change images directory to D:\TempRender\yourname\images )

Setup for Particles
In Window - Settings/Preferences - Preferences - Undo
       select Infinite Undos
Select the Timeline from the menu on the left
       Playback speed = Play Every frame
SAVE

Making particles:

Change to the Dynamics Menu Set
Rules of Physics apply, calculated frame by frame not using keyframes. Particles are designed to be animated using forces like wind and gravity. There are two types - hardware and software particles

Under Particles select the Particle Tool options

Enter a Name:

Conserve means the amount of momentum of the original particle that is conserved.
      1 = all momentum is conserved and fields won't effect the particles
      0 = no momentum (velocity) is conserved and fields have maximum effect

3 choices - Particles via clicking, Sketching Particles, or Particle Grid

Clicking
      Number of Particles - each time you click
      Maximum Radius - how far apart they could randomly be placed
      Hit Enter when done

Sketching
      Sketch Interval - how dense the particles will be
      Hit Enter when done

Grid
      Particle Spacing - how far apart the particles will be in the grid
      Placement: with cursor - place two points and hit Enter for a 2D grid
            with cursor - place 2 points and hit Insert and move one point down in a different view window for a 3D grid
                  Hit Insert again to turn off the Insert Mode and hit ENTER
            with textfield - enter the coordinates of the Lower Left Corner and Upper Right
                  Corner - move mouse into window and hit ENTER

To move a particle (before hitting Enter) use the Insert Key
To remove a particle or bunch of particles (before hitting Enter) use the Backspace Key
To remove all the particles in the object, after hitting Enter, hit Backspace

Can place particles on Live objects but they will not move with the object. You cannot group particles. Turn off the Live object when done.

Emitters
      Particles - Create Emitter Options
            Emitter Type - try Omni and Directional
            Rate (Particles/Sec) - determines how many particles get sent out per second

Particle Attributes (in Attribute Editor and some in Channel Box):

Particle Tab: can be keyed for whole particle not individual particles

Particle Attributes (default attributes) Transform & Shape Node (don't change Transform):
      Is Dynamic ON/OFF - off will make them uneffected by forces
      Dynamics Weight - effects of fields and collisions
            0 = fields connected to particles have no effect 1 = default effects - can set to .5
      Count - how many are there - can't edit this
      Max Count - used with particles created by an emitter
            only allows the Max # to exist - won't emit more until some die -1 = no limit

Render Attributes - to set particle type and add dynamic attributes
       Depth Sort - Improves render quality of transparent particles - drawn from far to near - slow
       Particle Render Type - particle type and how it renders

Hardware Rendered Particles with their attributes:

Will not render out when you do a Batch or Distributed Render
To get Attributes, click Add Attributes For: Current Render Type

Points - small dots
      Color Accum - when overlapping particles exist it uses an additive color effect in opacity and RGB - All colors = white
      Normal Dir - direction of the normal, only use if Use Lighting is turned on
            1 = forward; 2 = towards the camera; 3 = backwards
      Point Size = can increase or decrease size, far and near particles are the same size
      Use Lighting - uses lights from the scene. If OFF particles use their own color

Multipoint - each point is multiple points, particles seem denser, used for dust, mist, clouds
      Color Accum - when overlapping particles exist it uses an additive color effect in opacity and RGB - All colors = white
      Multi Count - # of particles displayed per particle
      Multi Radius - the sphere within which the particles for each individual particle is randomly distributed
      Normal Dir - direction of the normal, only use if Use Lighting is turned on
            1 = forward; 2 = towards the camera; 3 = backwards
      Point Size = can increase or decrease size, far and near particles are the same size
      Use Lighting - uses lights from the scene. If OFF particles use their own color

Streak - moving particles have tails, like meteors or rain. Streak length is based on velocity. If velocity is 0 you won't see a tail.
      Color Accum - when overlapping particles exist it uses an additive color effect in opacity and RGB - All colors = white
      Line Width - width of the streak
      Normal Dir - direction of the normal, only use if Use Lighting is turned on
             1 = forward; 2 = towards the camera; 3 = backwards
      Tail Fade - opacity of the tail fade; 1 = opaque, 0 = transparent
      Tail Size - length of the tail, faster the velocity the longer the tail.
            1 = default, 0 = none, less than 1 is shorter and more than 1 is longer
      Use Lighting - uses lights from the scene. If OFF particles use their own color

Multi Streak - Multipoint with a tail for each particle. Combo of Multipoint and Streak.
      Color Accum - when overlapping particles exist it uses an additive color effect in opacity and RGB - All colors = white
      Line Width - width of the streak
      Multi Count - # of particles displayed per particle
      Multi Radius - the sphere within which the particles for each individual particle is randomly distributed
      Normal Dir - direction of the normal, only use if Use Lighting is turned on
             1 = forward; 2 = towards the camera; 3 = backwards
      Tail Fade - opacity of the tail fade; 1 = opaque, 0 = transparent
      Tail Size - length of the tail, faster the velocity the longer the tail.
            1 = default, 0 = none, less than 1 is shorter and more than 1 is longer
      Use Lighting - uses lights from the scene. If OFF particles use their own color

Sprites - Displays a texture image at each point. Need to map an image on it. Image always faces camera, can be used for smoke, clouds, fog, and star field. If the image has an alpha channel on it then the alpha 0 will be transparent.
In Windows -> Rendering Editors -> Hypershade - make a Material and Color Map a FILE to it.
Assign the Material to the Particles (use the right mouse button on the material).
Turn on Shading - Smooth Shade All and Hardware Texturing
      Sprite Num - if you use a series of images which one to use in the series
      Sprite Scale X - .5 scales it 50% 2 scales it 200% in the X
      Sprite Scale Y - scaling in the Y
      Sprite Twist - - rotation of the sprite

Spheres - particles are spheres - does not work with transparency
      Radius - size of sphere

Numeric - puts the particle ID # on the particle - used for debugging
      Point Size - particle size
      Selected Only - select Components and only those will have numbers
      Try entering position, velocity, mass and lifespan into the attributeName field

Making images for your sprite particles:

In Photoshop draw or scan in an image.
Select the part you want to be transparent.
Select - Inverse Selection
Select - Save Selection
Save As .... TIF

Put the image in your sourceimages folder

In the Hypershade, make a Lambert or Phong and attach a file texture to it.
      (select the image with the alpha channel)
Select the particles
In the Hypershade, hold down the middle arrow on the shader (Phong or Lambert)
Select Assign Material to Selection

In the modeling window, hit 5, 6 to see the results

Add Dynamic attributes:

(don't add them unless needed - they use memory and compute time)
Select Per Object and it will add the new attribute to the Render Attributes

Per Object
      Opacity - 0 = transparent; 1 = opaque
      Color: Per Object
            Per object gives you RGB values to work with - does not show up until you hit the 5 6 7 keys
Per Particle
      Requires programming or advanced techniques (we will do this later)

Lifespan Attributes - determines when the particle dies

Number of seconds it lives after it is born. Used with emitters.
      Live forever - never dies
      Constant - lives for a specific time
      Random - lifespan = average life, random = total distribution