昨天看了徐医生的费塞尔曲线艺术，然后把上面的例子手打了一遍，受益匪浅.下面的下雪的效果的Layout就是根据费塞尔三阶曲线画出的轨迹.
Step 1. Add the JitPack repository to your build file Add it in your root build.gradle at the end of repositories:
allprojects {
repositories {
...
maven { url "https://jitpack.io" }
}
}
Step 2. Add the dependency
dependencies {
compile 'com.github.shellljx:SnowLayout:v1.1.1'
}
Step 3.
mSnowLayout = (SnowLayout) findViewById(R.id.snowLayout);
mDrawables[0] = ContextCompat.getDrawable(this, R.mipmap.ic_snow1);
mDrawables[1] = ContextCompat.getDrawable(this, R.mipmap.ic_snow2);
mDrawables[2] = ContextCompat.getDrawable(this, R.mipmap.ic_snow3);
mDrawables[3] = ContextCompat.getDrawable(this, R.mipmap.ic_snow4);
mDrawables[4] = ContextCompat.getDrawable(this, R.mipmap.ic_snow5);
mDrawables[5] = ContextCompat.getDrawable(this, R.mipmap.ic_snow6);
mSnowLayout.setDrawables(mDrawables);
mSnowLayout.start();
