tailieunhanh - Mastering Autodesk Maya 2011 phần 8

Up trong không gian đối tượng có nghĩa là phía trên của đối tượng. Nếu đối tượng là xoay lộn ngược trong không gian thế giới, hàng đầu vẫn là hàng đầu để đầu của robot vẫn là hàng đầu của đối tượng trong không gian đối tượng ngay cả khi nó treo lộn ngược. | 706 chapter 13 introducing NPARTICLES 4. Switch to a side view and turn on wireframe mode. 5. Play the animation and observe the behavior of the nParticles. If you look at the Collisions settings for moltenMetal you ll see that the Self Collide attribute is off but the nParticles are clearly colliding with each other. This type of collision is part of the liquid behavior defined by the Incompressibility attribute this is discussed a little later in the chapter . 6. Play the animation back several times notice the behavior when A. Enable Liquid Behavior is off. B. Self Collide is on set Self Collide Width Scale to . c. Both Liquid Behavior and Self Collide are enabled. 7. Turn Liquid Behavior back on and turn Self Collide off. 8. Open the Particle Size rollout panel and set Radius to play the animation. There seems to be much less fluid for the same number of particles when the radius size is lowered. 9. Play the animation for about 140 frames until all the nParticles settle. 10. With the moltenMetal shape selected choose nSolvers Initial State Set From Current. 11. Rewind and play the animation the particles start out as settled in the well of the tub see Figure . FIGURE Setting Initial State makes the nParticles start out from their settled position. 12. Select moltenMetal. At the top of the Attribute Editor deselect Enable to temporarily disable the nParticle simulation so you can easily animate the tub. 13. Select the tubl group in the Outliner and switch to the side view. 14. Select the Move tool hot key w . Hold the d key on the keyboard and move the pivot for tub1 so it s aligned with the center of the handles that hold it in the frame see Figure . 15. Set the timeline to frame 20. 16. In the Channel Box select the Rotate X channel for the tubl group node right-click and set a keyframe. 17. Set the timeline to frame 100. 18. Set the value of tubl s Rotate X channel to 85 and set another key. using nparticles to simulate liquids 707