INTRODUCTION
This is my next tutorial for 3dsmax 7. There was a nice response to the first tutorial but the 2nd and 3rd....the less we talk about it the better.
Anyway this time i decided to shift back to reactor, something that fascinates me. My previous tutorial was something that wasnt very realistic
so this time im going to teach you something more realistic.
Im sure most of you will agree that collisions are very tough to animate, so reactor basically makes your life easier not only on that account but
on many other "Physical" aspects of an animation too. I am not very familiar with the other areas so i will not delve into that as of now. Now,
imagine a box filled with balls. You throw another ball at it and make it topple. Now, what would happen? If one was to animate the sequence
manually it would be very complex so here i make it a lot easier. Yes we would animate the baox toppling, the balls falling and then the aftermath.
This entire sequence is very simple if you follow my steps as they are. In my last tutorial i got many e-mails from people who had missed some or
the other step and hence the 'reaction' (pun intended) was not as expected. This sequence basically contains of the following steps.
I Object creation
a)Box
b)Balls
c)Projectile
d)Plane
II Setting up the reaction
a)Applying mass properties
b)Providing the initial velocity
c)Previewing animation
III Final Rendering
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Before you begin, please reset 3dsmax. You can do this by going to File-> Reset.
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I Object Creation
a)Box
To create the box do the following
1. Create 5 small boxes with dimensions Length and Width = 400 and Height = 25
2. Arrange the boxes to form a larger hollow box.
3. Select and right-click the box used as the base of the box, and in the Transform quadrant of the quad menu, choose Convert To > Convert To
Editable Mesh.
4.In the Edit Geometry rollout of the Modify panel, click Attach List.
5.In the Attach List dialog, select the other four boxes, which make up the sides of the box, and click Attach.
You now have a single mesh representing the box.
Balls1. Now create a sphere of radius 25 in the box but make sure that the sphere does not touch the box.
2.Now select the move button. Press SHIFT and move the sphere upwards till it does not touch the other sphere. Now leave the mouse button.
3.In the dialog box change the value of no. of clones to 39.
c) Projectile
1. Create another sphere of radius 25 outside the box but in line with the box at a distance from it.
d) Plane
1. Create another large box of Length=Width=4000 and Height= 25
2. Move it so that it is just below the other box that we have created.
3. Also make sure that the smaller box is on the edge of this box that we have just created.
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We have now finished the setting up of the scene, we need not create any new objects here onward but just have to keep making some modifications till the final result is achieved. Now we play with reactor.
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II REACTOR
a) Creating a rigid body collection.
1. Select all the objects that you have created by pressing Ctrl+A
2.Now goto reactor->Create Object-> Create rigid body collection.
3.Now click on the select by name option and select all the spheres EXCEPT the projectile.
4.Goto reactor->Open Property Editor.
5. Change the mass value to 50
6. Now select the two boxes and open their reactor property editors.
7. Change Simulation Geometry to Concex Mesh.
8. Goto reactor->Preview Animation.
9. Press 'P'. Watch all the spheres fall into the box. Allow them to settle in the box.
10. Then in the preview window goto MAX->Update MAX.
11. Close the preview window.
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Now, we have created the balls in the box as they would be when the collision will take place. We will now give the projectile it's initial velocity.
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b)Providing the initial velocity.
1. Select the projectile.
2. Click on Autokey.
3. Change the frame to 10
4. Move the sphere to the other side of the box.
5. Switch of autokey.
6. On the upper right hand side you see some icons. Click on the icon that would say 'utilities' on mouse over. It looks like a hammer.
7. In the list click on reactor.
8. Under preview and animation change the start frame value to 2 and end frame value to 500.
9. Now open the reactor property editor of the projectile.
10. Change mass value to 100 and select 'Bounding Sphere' under simulation geometry.
11. Now preview the final animation.
12. If you are satisfied with the result do the following bwfore you render the final sequence.
13. In the lower right corner of the screen there is a button with a clock on it which says 'Time Configuration'. Click on it and change end time to
500.
14. Now goto Reactor->Create Animation.
15. Play the entire animation in the main window. If you are happy with the entire animation you can render the scene.
III FINAL RENDERING
1. Click on rendering->Render....
2. In the dialog box. Select 'Active Time Segment' under Time Output
3. Under Render output apecify a file location and name.
4. Finally click on 'Render' Button and wait.
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Congratulations you have completed the basic tutorial.
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ADVANCED USER OPTIONS
Here are a few more ideas for advanced users.
*You can create a reflective plane and get a cool looking effect
*Creating a camera and linking it to some object or even manully animating a fly around sequence.
*Rendering from multiple angles and then putting them together in one slick video.
*Playing with lights and shadows
* Creating a daylight system and using more types of textures for the plane, box and the balls to make it seem like a real life situation.
Have Fun!
If you have any problems feel free to contact me at meetnakul@hotmail.com
Certainly very usefull 
I guess it took a lot of time to write it all down, so respect for that !
