The gradient is defined by four effect points, the positions and colors of which can be animated using the Positions & Colors controls.
该渐变被四个作用点控制，作用点的位置和颜色可以通过位置和颜色参数的变化制作动画。
2
Coal maceral concentrates of high purity were prepared from four different rank coals by Density Gradient Centrifugation method.
经等密度梯度离心分离，从褐煤、长焰煤、气煤和贫煤四种不同变质程度煤中获得了高纯度的有机显微组分。
3
Aiming at characteristic differences of background and target, four-direction gradient is extracted out and areas with large gradient are smoothed by a linear threshold filter.