Curl Noise就是使用Perlin Noise作为Potenial Field,计算出旋度场Curl Field来作为速度场Velocity Field,即\vec v(x,y) = curl \vec \Psi(x,y)\\计算出Velocity Field后对不同点的粒子的速度施加该点相应的\Delta V,就实现了粒子流动的效果。以二维情况为例。以Perlin Noise定义二维平面下的原始势力场\vec ...
To find the maximum we have to take the derivative of that function and solve for zero, because where the rate of change is zero the function has reached a maximum or minimum. Solving that equation is possible but nontrivial. To get an idea of what the function looks like we can visuali...
Consider a point (x, y, z) and some function F(x, y, z) that you've defined in your pixel shader through some combination of noise functions. Choose some small value of e and compute the following quantities: This allows a good approximation of the gradient (or derivative) vector...
首先从一维说起,假如我们需要得到一维点x的noise,首先我们取x附近的两个整数点的noise值,然后利用插值函数得到该点的noise。具体计算如下: //注释掉的为原始的插值函数,非二次连续,高频突变。floatfade(floatt) {//return t*t*(3.0-2.0*t);//Old fade, yields discontinuous second derivativereturnt*t*t*(...