CPU-based 2D particle emitter. CPU-based 2D particle node used to create a variety of particle systems and effects. See also [Particles2D], which provides the same functionality with hardware acceleration, but may not run on older devices. https://docs.godotengine.org/en/latest/tutorials/2d/particle_systems_2d.html Sets this node's properties to match a given [Particles2D] node with an assigned [ParticlesMaterial]. Restarts the particle emitter. Number of particles emitted in one emission cycle. Initial rotation applied to each particle, in degrees. Each particle's rotation will be animated along this [Curve]. Rotation randomness ratio. Default value: [code]0[/code]. Initial angular velocity applied to each particle. Sets the speed of rotation of the particle. Each particle's angular velocity will vary along this [Curve]. Angular velocity randomness ratio. Default value: [code]0[/code]. Particle animation offset. Each particle's animation offset will vary along this [Curve]. Animation offset randomness ratio. Default value: [code]0[/code]. Particle animation speed. Each particle's animation speed will vary along this [Curve]. Animation speed randomness ratio. Default value: [code]0[/code]. Each particle's initial color. If [member texture] is defined, it will be multiplied by this color. Each particle's color will vary along this [Gradient]. The rate at which particles lose velocity. Damping will vary along this [Curve]. Damping randomness ratio. Default value: [code]0[/code]. Particle draw order. Uses [enum DrawOrder] values. Default value: [constant DRAW_ORDER_INDEX]. The rectangle's extents if [member emission_shape] is set to [const EMISSION_SHAPE_RECTANGLE]. Particles will be emitted inside this region. Use [enum EmissionShape] for values. Default value: [constant EMISSION_SHAPE_POINT]. The circle's radius if [member emission_shape] is set to [const EMISSION_SHAPE_CIRCLE]. If [code]true[/code], particles are being emitted. Default value: [code]true[/code]. How rapidly particles in an emission cycle are emitted. If greater than [code]0[/code], there will be a gap in emissions before the next cycle begins. Default value: [code]0[/code]. The particle system's frame rate is fixed to a value. For instance, changing the value to 2 will make the particles render at 2 frames per second. Note this does not slow down the simulation of the particle system itself. Align y-axis of particle with the direction of its velocity. If [code]true[/code], results in fractional delta calculation which has a smoother particles display effect. Default value: [code]true[/code] Gravity applied to every particle. Default value: [code](0, 98)[/code]. Initial hue variation applied to each particle. Each particle's hue will vary along this [Curve]. Hue variation randomness ratio. Default value: [code]0[/code]. Initial velocity magnitude for each particle. Direction comes from [member spread] and the node's orientation. Initial velocity randomness ratio. Default value: [code]0[/code]. Amount of time each particle will exist. Default value: [code]1[/code]. Linear acceleration applied to each particle in the direction of motion. Each particle's linear acceleration will vary along this [Curve]. Linear acceleration randomness ratio. Default value: [code]0[/code]. If [code]true[/code], particles use the parent node's coordinate space. If [code]false[/code], they use global coordinates. Default value: [code]true[/code]. Normal map to be used for the [member texture] property. If [code]true[/code], only one emission cycle occurs. If set [code]true[/code] during a cycle, emission will stop at the cycle's end. Default value: [code]false[/code]. Particle system starts as if it had already run for this many seconds. Radial acceleration applied to each particle. Makes particle accelerate away from origin. Each particle's radial acceleration will vary along this [Curve]. Radial acceleration randomness ratio. Default value: [code]0[/code]. Emission lifetime randomness ratio. Default value: [code]0[/code]. Initial scale applied to each particle. Each particle's scale will vary along this [Curve]. Scale randomness ratio. Default value: [code]0[/code]. Particle system's running speed scaling ratio. Default value: [code]1[/code]. A value of [code]0[/code] can be used to pause the particles. Each particle's initial direction range from [code]+spread[/code] to [code]-spread[/code] degrees. Default value: [code]45[/code]. Tangential acceleration applied to each particle. Tangential acceleration is perpendicular to the particle's velocity giving the particles a swirling motion. Each particle's tangential acceleration will vary along this [Curve]. Tangential acceleration randomness ratio. Default value: [code]0[/code]. Particle texture. If [code]null[/code] particles will be squares. Particles are drawn in the order emitted. Particles are drawn in order of remaining lifetime. Use with [method set_param], [method set_param_randomness], and [method set_param_texture] to set initial velocity properties. Use with [method set_param], [method set_param_randomness], and [method set_param_texture] to set angular velocity properties. Use with [method set_param], [method set_param_randomness], and [method set_param_texture] to set orbital velocity properties. Use with [method set_param], [method set_param_randomness], and [method set_param_texture] to set linear acceleration properties. Use with [method set_param], [method set_param_randomness], and [method set_param_texture] to set radial acceleration properties. Use with [method set_param], [method set_param_randomness], and [method set_param_texture] to set tangential acceleration properties. Use with [method set_param], [method set_param_randomness], and [method set_param_texture] to set damping properties. Use with [method set_param], [method set_param_randomness], and [method set_param_texture] to set angle properties. Use with [method set_param], [method set_param_randomness], and [method set_param_texture] to set scale properties. Use with [method set_param], [method set_param_randomness], and [method set_param_texture] to set hue variation properties. Use with [method set_param], [method set_param_randomness], and [method set_param_texture] to set animation speed properties. Use with [method set_param], [method set_param_randomness], and [method set_param_texture] to set animation offset properties. Represents the size of the [enum Parameter] enum. Use with [method set_flag] to set [member flag_align_y]. All particles will be emitted from a single point. Particles will be emitted on the perimeter of a circle. Particles will be emitted in the area of a rectangle. Particles will be emitted at a position determined by sampling a random point on the [member emission_point_texture]. Particle color will be modulated by [member emission_color_texture]. Particles will be emitted at a position determined by sampling a random point on the [member emission_point_texture]. Particle velocity and rotation will be set based on [member emission_normal_texture]. Particle color will be modulated by [member emission_color_texture].