效果图如下:
效果是别人做的,非本人所写,本人只是分析下实现原理而已:)
代码原理:
1. 所有的View都将backedLayer替换成了粒子Layer
2. 粒子随着路径运动的动画代码如下,keyPath很少见哦,粒子的位置,学习了.
3. 爆炸效果如何产生的?
LYFireworksView.m
附录:
CAEmitterCell的一些可以动画的属性:
这么多可供动画用参数,应该可以实现非常复杂的效果吧.
/* The name of the cell. Used to construct key paths. Defaults to nil. */
@property(copy) NSString *name;
/* Controls whether or not cells from this emitter are rendered. */
@property(getter=isEnabled) BOOL enabled;
/* The number of emitted objects created every second. Default value is
* zero. Animatable. */
@property float birthRate;
/* The lifetime of each emitted object in seconds, specified as a mean
* value and a range about the mean. Both values default to zero.
* Animatable. */
@property float lifetime, lifetimeRange;
/* The orientation of the emission angle in radians, relative to the
* natural orientation angle of the emission shape. Note that latitude
* here is what is typically called colatitude, the zenith or phi, the
* angle from the z-axis. Similarly longitude is the angle in the
* xy-plane from the x-axis, often referred to as the azimuth or
* theta. Both values default to zero, which translates to no change
* relative to the emission shape's direction. Both values are
* animatable. */
@property CGFloat emissionLatitude, emissionLongitude;
/* An angle (in radians) defining a cone around the emission angle.
* Emitted objects are uniformly distributed across this cone. Defaults
* to zero. Animatable. */
@property CGFloat emissionRange;
/* The initial mean velocity of each emitted object, and its range. Both
* values default to zero. Animatable. */
@property CGFloat velocity, velocityRange;
/* The acceleration vector applied to emitted objects. Defaults to
* (0, 0, 0). Animatable. */
@property CGFloat xAcceleration, yAcceleration, zAcceleration;
/* The scale factor applied to each emitted object, defined as mean and
* range about the mean. Scale defaults to one, range to zero.
* Animatable. */
@property CGFloat scale, scaleRange, scaleSpeed;
/* The rotation speed applied to each emitted object, defined as mean
* and range about the mean. Defaults to zero. Animatable. */
@property CGFloat spin, spinRange;
/* The mean color of each emitted object, and the range from that mean
* color. `color' defaults to opaque white, `colorRange' to (0, 0, 0,
* 0). Animatable. */
@property CGColorRef color;
@property float redRange, greenRange, blueRange, alphaRange;
/* The speed at which color components of emitted objects change over
* their lifetime, defined as the rate of change per second. Defaults
* to (0, 0, 0, 0). Animatable. */
@property float redSpeed, greenSpeed, blueSpeed, alphaSpeed;
/* The cell contents, typically a CGImageRef. Defaults to nil.
* Animatable. */
@property(retain) id contents;
/* The sub-rectangle of the contents image that will be drawn. See
* CALayer.h for more details. Defaults to the unit rectangle [0 0 1 1].
* Animatable. */
@property CGRect contentsRect;
/* The filter parameters used when rendering the `contents' image. See
* CALayer.h for more details. */
@property(copy) NSString *minificationFilter, *magnificationFilter;
@property float minificationFilterBias;
/* An array containing the sub-cells of this cell, or nil (the default
* value). When non-nil each particle emitted by the cell will act as
* an emitter for each of the cell's sub-cells. The emission point is
* the current particle position and the emission angle is relative to
* the current direction of the particle. Animatable. */