tutorial_particles_2d
A simple (but flexible enough for most uses) particle system is provided. Particle systems are used to simulate complex physical effects such as sparks, fire, magic particles, smoke, mist, magic, etc.
The idea is that a "particle" is emitted every a fixed interval and with a fixed lifetime. During his lifetime, every particle will have the same base behavior. What makes every particle different and provides a more organic look is the "randomness" associated to each parameter. In essence, creating a particle system means setting base physics parameters and then adding randomness to them.
Particle systems are added to the scene via the Particles2D node. They are enabled by default and start emitting white points downwards (as affected by the gravity). This provides a reasonable starting point to start adapting it to our needs.
A particle system uses a single texture (in the future this might be extended to animated textures via spritesheet). The texture is set via the relevant texture property:
Before taking a look at the global parameters for the particle system, let's first see what happens when the physics variables are tweaked.
This is the base angle at which particles emit. Default is 0 (down):
Changing it will change the emissor direction, but gravity will still affect them:
This parameter is useful because, by rotating the node, gravity will also be rotated. Changing direction keeps them separate.
Spread is the angle at which particles will randomly be emitted. Increasing the spread will increase the angle. A spread of 180 will emit in all directions.
