# Phun

Published Date
01 - May - 2008
| Last Updated
01 - May - 2008

Phunny Physics

Phun! If you think we are not in our senses and that it’s a weird way to say fun, then here goes—it’s a free 2D physics simulation we gave out on the April ‘08 DVD. In short, you draw objects like you would on paper and all the drawings react with each other as though they are real. There’s a lot to play around with, but where do you begin?

Understanding The Phundamental Operations

Before we start, here’s a very basic introduction on how you handle objects and the workspace in Phun. You can create objects by clicking on the shapes in the toolbar on the left, and then clicking and dragging the scene. To draw your own custom shapes, choose the Brush tool and draw a shape but make sure you complete the loop. To rotate an object, right-click on the object and move it.

In typical empty scenes, there is no ground. Use the plane tool to draw a plane or all your objects will fall through empty space. If you want objects to be attached in the space, then click on the Fixate tool and click on the object created. When you have all the objects in place, you can press the Play button under Control. Everything now in the scene will react in real-time. To move objects around, you need to click the Drag tool. To navigate around the workspace, right-click and drag the scene. The mouse scroll can be used to zoom in and out.

Hinges can be set up to act as motors

Hinges allow you to fix objects and allow other objects to latch on to them and at the same time be allowed some movement. Adding hinges in Phun can be done by simply creating the object that you want to fixate. Use the Hinge tool, and then click on a suitable location such as one end of the extremities of the object to allow a free movement. Click the Play button to have the object start rotating by gravity. The same hinge can also be converted to a motor. Right-click on the hinge and click on Hinges > Motor. Click the Motor checkbox to enable it. You can also choose the speed and power of the motor. To be able to manually control the motor, click on Control with arrow keys. Use the left and right arrow keys to control the speed of the motor.

Springs are yet another component in Phun which allow two objects to interact. In springs, you can add tension between two objects just like any other spring. Similar to hinges, first create the object you to attach the strings to. Click the Spring tool and drag a spring from the blank space or one object to another. Spring properties such as strength and dampening can be changed by right-clicking on the spring and then choose Spring in the menu that pops up.

Chains are also attached in the same manner as springs by dragging lines between two points after selecting the Chain tool. Unlike springs, chains can be created without being attached to other objects. Chains can also be set up as motors like hinges by right-clicking on it and clicking on Chain again.

Creating And Grouping Objects

Keeping track of little objects can be a headache. If you’re someone who is used to playing RTS games such as Warcraft III, then the same technique is used to create groups here. First, select the objects you want in your groups by drawing an enclosure using the brush tool. Press [Ctrl] [number] to add all the selected objects to that group. To select the group, press that number again.

Liquid Simulation

Phun can do liquid simulations too. Liquids can’t be created directly so you need to create shapes and then convert them to liquids.

Solid objects need to be converted to create liquids

So first draw the shapes like you normally would, then right click on the object and then click on Geometry settings > Liquify selected.

Some performance tweaks are necessary in CPU intensive simulations such as fluids

Tweaking Phun for Quality or Performance

Phun simulates everything in real-time so all the physics processing needs to be done in real-time by your processor. It’s a heavy and strenuous task for the machine so a few settings can be altered when your scene becomes too complex to render smoothly. Click on Options under File and uncheck the box for Enable shaders and Draw clouds and check the one for Simple water rendering. If your machine handles Phun perfectly fine, then by all means leave shaders and clouds on and turn off simple water rendering.

If you’re still left baffled by the things you can do with Phun, just load some ready made scenarios by clicking on File > Load Scene. You can then modify them or learn some new tricks from them.

Rossi Fernandes