Limitations and Future Work

Except for the physics-based simulation, we also pay attention to the controllability which is curial for animators. We utilize the control particles to guide the whole fluid volume flowing direction, which may preserve more fluid detail from the fluid solver. And we design two types of control mechanism, the path control can lead the fluid flow along the path, and the shape control has the ability to constraint the melting fluid to form our desire shape automatically.

Besides the force control for particle movement, we additional control the temperature variables to achieve our goal during the melting process.

The results demonstrate that our method can melting several different materials naturally.

And the animators can easily design the melting scene by the intuitive sketching tools.

5.2 Limitations and Future Work

Our object melting and flowing control framework is able to deal with a wide range of materials, and provide a realistic melting process. But there are still some limitations in our approach. For real objecting melting process, there are plenty of details (e.g. small droplet) flowing on the surface. Current object surface in our framework is reconstructed by marching cube algorithm, it is hard to avoid some small details are smoothing during the polygon creation. Moreover, since our control mechanism is a force-based system, it is difficult to control each particle to the the target position precisely. Finally, we have not try to simulate inhomogeneous materials in this thesis. The inhomogeneous material contains different material types in a single object, which makes the interaction between particles more complicate.

In the future, we would like to enhance the surface detail by applying more recently surface reconstruction method, such as adaptive marching cube or other advance techniques. Besides, currently our computational cost bottleneck is on the thermal simulation part, more particle number in thermal exchanging stage may lower down the simulation speed. To apply a impor-tant sampling scheme in thermal simulation maybe a good idea to improve the efficiency. The region of interest may use more samples to capture the accurate thermal transfer result, and the other region may use less particles for a sufficient simulation. Lastly, we are now focusing on

5.2 Limitations and Future Work 52

extending the path control works to form a 3D target. The path can be done by some mesh information like skeleton, and the nodes can store local volume inside the mesh and the contour around the path node. Hopefully, this control mechanism could help the melting fluid to form any given target shape.

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