Gravitation3D Tips and Troubleshooting

Tips

Tip:  Try to control the Animation Speed with the slider control, not the time step!

Though the time step has a visual effect on how fast your system evolves, it is better to speed up your simulation with the animation controls.  The reason is that though a larger time step will appear to speed things up, it also makes the calculations less accurate and your system more unstable.

Tip: Hacking the Definition File

You are encouraged to muck with the saved Gravitation3D files using a text editor!  You will find a few goodies in there.  There are some items not controllable through the UI (planned V2.0 features that are not yet maturely developed) and some items I didn’t want to give the more casual user control over.  The file was designed to be readable. 

There is, of course, no guarantee that Gravitation3D will be able to read your changes or deal with them properly, so you might want to make a backup of any solar system with which you decide to go alter the internals.  There is also no guarantee that everything you see in the definition file currently even does something.

Troubleshooting

My simulations run sloooooooow!  

This program is meant to run on a modern machine with a graphics accelerated video card.  However, some features are more intensive than others and can be changed to improve performance.  Among the items you can change are:

• Trails:  Turning down the Trail Length or Trail Accuracy on the Drawing Tab is one of the best ways to improve speed.  Drawing every simulation point just becomes a lot for the computer to handle.  Trails are one of the main reasons Version 1.0 limits the simulations to 100,000 steps.  Unchecking “Fade Trails” can also help.

• I’ve noticed on my home Pentium III, NVidia TNT2 that the text actually slows things dramatically.  Though you can’t turn off the registration text without registering, turning the axes labels off can help.

• Other things to try

            Lower the star count or don’t display stars.

            Plane warping is a cool effect, but can be expensive.

            Ghost collisions are less intensive than Elastic or Inelastic collisions.

            Don’t view in wireframe (surprisingly this is slower than filled mode).

I’ve added planets but can’t see them!

• Make sure all your radii have positive values that are reasonably sized relative to the overall scale of your system. 

• On the scaling page, if you drag the first Radii Scaling slider closer to “uniform”, this should help planets with small radii to come into view.

I can't edit planet values!

• You need to be in the reset state.  Press ‘R’ or push the reset button on the simulations pane.

How come I can’t zoom out with some of the sample systems??

            The view may be slaved to a planet, so check this if the mouse doesn’t seem to be helping.