Preliminary understanding of Panda3D particle system

function panda3d Example Tut-Particle-Panel.py; A basic particle system appears as follows ;

At the same time, the particle system panel appears as follows ;

 

    The programming principle of particle system should be to specify the emission position of particles 、 Number 、 Particle size 、 Color and other parameters , Then the engine makes it ;

    Adjust the panel parameters , Basically no effect was found ;

I studied it , Its particle system configuration is *.ptf file ; Load different ptf file , Take a look at the effect ;

 

 

    wait ;

Open one ptf Take a look at the document ; Is the plain text , It can be edited manually ; An example is as follows ;

self.reset()
self.setPos(0.000, 0.000, 0.000)
self.setHpr(0.000, 0.000, 0.000)
self.setScale(1.000, 1.000, 1.000)
p0 = Particles.Particles('particles-1')
# Particles parameters
p0.setFactory("PointParticleFactory")
p0.setRenderer("PointParticleRenderer")
p0.setEmitter("DiscEmitter")
p0.setPoolSize(10000)
p0.setBirthRate(0.0200)
p0.setLitterSize(300)
p0.setLitterSpread(100)
p0.setSystemLifespan(0.0000)
p0.setLocalVelocityFlag(1)
p0.setSystemGrowsOlderFlag(0)
# Factory parameters
p0.factory.setLifespanBase(0.5000)
p0.factory.setLifespanSpread(0.2500)
p0.factory.setMassBase(2.0000)
p0.factory.setMassSpread(0.0100)
p0.factory.setTerminalVelocityBase(400.0000)
p0.factory.setTerminalVelocitySpread(0.0000)
# Point factory parameters
# Renderer parameters
p0.renderer.setAlphaMode(BaseParticleRenderer.PRALPHAOUT)
p0.renderer.setUserAlpha(0.45)
# Point parameters
p0.renderer.setPointSize(3.00)
p0.renderer.setStartColor(Vec4(0.25, 0.90, 1.00, 1.00))
p0.renderer.setEndColor(Vec4(1.00, 1.00, 1.00, 1.00))
p0.renderer.setBlendType(PointParticleRenderer.PPONECOLOR)
p0.renderer.setBlendMethod(BaseParticleRenderer.PPNOBLEND)
# Emitter parameters
p0.emitter.setEmissionType(BaseParticleEmitter.ETCUSTOM)
p0.emitter.setAmplitude(1.0000)
p0.emitter.setAmplitudeSpread(0.0000)
p0.emitter.setOffsetForce(Vec3(0.0000, 0.0000, 4.0000))
p0.emitter.setExplicitLaunchVector(Vec3(1.0000, 0.0000, 0.0000))
p0.emitter.setRadiateOrigin(Point3(0.0000, 0.0000, 0.0000))
# Disc parameters
p0.emitter.setRadius(0.0500)
p0.emitter.setOuterAngle(356.1859)
p0.emitter.setInnerAngle(0.0000)
p0.emitter.setOuterMagnitude(2.0000)
p0.emitter.setInnerMagnitude(1.0000)
p0.emitter.setCubicLerping(0)
self.addParticles(p0)
f0 = ForceGroup.ForceGroup('gravity')
# Force parameters
force0 = LinearVectorForce(Vec3(0.0000, 0.0000, -1.0000), 25.0000, 1)
force0.setActive(1)
f0.addForce(force0)
force1 = LinearJitterForce(3.0000, 1)
force1.setActive(1)
f0.addForce(force1)
self.addForceGroup(f0)

Display the... Of the particle system panel python The code is as follows ;

import sys
import direct.directbase.DirectStart

base.startTk()

from direct.tkpanels.ParticlePanel import ParticlePanel

pp = ParticlePanel()             # Create the panel
base.disableMouse()              # Disable camera control to place it
camera.setY(-10)                 # Place the camera
base.setBackgroundColor(0, 0, 0) # Most particle systems show up better on black backgrounds
run()   

Particle systems are usually superimposed on the model to make some effects , For example, simulate building fire ;

BaseParticleRenderer Is the base class of particle system ;

The categories of particle systems include ： Geometric particles , Line segment particle , Point particles , Pyrotechnic particles , spirit ;

classBaseParticleRenderer
Bases:

Bases: ReferenceCount

Pure virtual particle renderer base class

    This class is a pure virtual class ; When programming, use derived concrete classes ;