To effectively control particle‐based cloud evolution without imposing strict position constraints, we propose a novel method integrating a control force field and a phase transition control into the position‐based fluids (PBF) framework. To produce realistic cloud simulation, we incorporate both fluid dynamics and thermodynamics to govern cloud particle movement. The fluid dynamics is simulated through our novel driving and damping force terms. As these terms are only formulated based on cloud particle density and position, they simplify the inputs and make our method free from artificial positional constraints. The thermodynamics is implemented by our phase transition control, which can effectively simulate cloud evolution between discrepant initial and target shapes, producing plausible results. Uniquely, our method can also support target shape change during cloud simulation. Experiment results have demonstrated our method surpasses existing methods.

中文翻译：

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使用基于位置的流体的目标驱动的云演化

为了在不施加严格位置约束的情况下有效控制基于粒子的云演化，我们提出了一种将控制力场和相变控制集成到基于位置的流体（PBF）框架中的新方法。为了产生逼真的云模拟，我们结合了流体动力学和热力学来控制云粒子运动。通过我们新颖的驱动力和阻尼力项来模拟流体动力学。由于这些术语仅基于云粒子密度和位置制定，因此它们简化了输入并使我们的方法不受人为位置约束。热力学由我们的相变控制实现，它可以有效地模拟不同的初始形状和目标形状之间的云演化，产生合理的结果。独一无二，我们的方法还可以支持云模拟过程中的目标形状变化。实验结果证明我们的方法超越了现有的方法。