Blender Tutorial

Animation: Falling Object into Liquid

This tutorial walks through how to make an object fall into a liquid.

Create Liquid

1. CTRL-x, Enter
2. NUM1
3. s, z, .5, Enter
4. g, z, .5, Enter
5. Press F7 then F7 again.
6. Click Enable in the Fluid Simulation panel.
7. Click Fluid.

Create Domain

The domain the area in which objects that affect the liquid must reside.

1. z
2. Add » Mesh » Cube
3. g, z, 1, Enter
4. a
5. CTRL-Tab, 3
6. Click RMB to select the top face of the cube.

   

   The Domain Cube

7. g, z, 1, Enter
8. Click Enable in the Fluid Simulation panel.
9. Click Domain.

Create Falling Object

1. Tab
2. NUM7
3. Add » Mesh » UVsphere
4. Click OK then click the second OK.
5. Tab
6. s, .1, Enter
7. g, z, 2.5, Enter
8. NUM1
9. Click Enable in the Fluid Simulation panel.

   To interact with fluid, the object must have fluid simulation properties.

10. Click Obstacle.
11. Click Init Shell.
12. F4
13. Click Actor.

    To fall, the object must be an actor in the scene.

14. Click Dynamic.
15. Click Rigid Body.
16. Click Bounds.
17. Select Convex Hull Polytope.

    

    Boundary Display Menu

18. Press p to play the animation, then ESC to continue.

    The ball does not fall through the water, yet, but its motion is realistic.

Move Liquid

1. Click RMB to select the liquid cube (Cube).

   

   Selected Fluid Cube

2. Press m then 2 then Enter to move the liquid to layer 2.
3. Press p to play the animation, then ESC to continue.

   The ball now falls through the area where the water will be.

Baking

To calculate the movement of meshes that represent liquids (within the confines of a domain), Blender must first create a series of mesh models for the steps in an animated sequence.

1. Click RMB to select the domain cube (Cube.001).

   

   Selected Domain Cube

2. F10
3. Change End: from 250 to 40.

   Eventually you will want a higher number than 40 as this controls the number of frames in which the animation will be recorded. A higher number means more frames, which, in turn, means a longer time to bake and render.

4. F7
5. Provide a file name (e.g., //bake/fall).
6. F9
7. Click Set Smooth.
8. Click BAKE.

   As soon as you start scratching your head, wondering why the little ball has not started to fall, press ESC.

Register the Fall

1. Game » Record Game Physics to IPO
2. Game » Enable All Frames
3. Press p to play the animated fall.

   These steps magically register the movement of the ball with its fall.

4. Click BAKE.
5. Press ALT-a to preview the fall.
6. Press ESC to stop the preview.

Render

1. Render » Render Animation
2. Stretch your legs, call your grandmother(s), return in several minutes.

   

   Final Frame in Animation

THE END - Download Video