Author's Notes from Sayu

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Please note that this may not be complete. You shouldn't expect it to be updated soon, or necessarily ever, but don't be surprised if there are little quirks I haven't noted here.

Notes from the Author

* Distkills and planets outside the window
Be careful when setting your initial conditions, especially if your windowing system isn't set to store grfxgrav's size. Grfxgrav does not currently store size or position between sessions; therefore the size of the window will always be the default. If distkills is set, planets outside of the window will die in fairly short order and never return, possibly turning into solar flares if sunflares is enabled. Sometimes it's interesting to get rid of some of the particles by quickly resizing the window in and back, but consistently losing outlying planets can be a hassle. Or, not; whatever.

* Gravity and the Gravitational Constant G
Under Single Gravitation, G is used instead of G*M for the gravitation equation, g=GMm/d^2. Under universal gravitation, however, G is the latter, the mathetmatical constant. That is to say, I don't deal with masses under Single Gravitation, including that of the sun, and so 'G' is implied to already be multiplied with the sun's mass.

* The Velocity Constant and the New Equation
Under the old equation and single gravitation, I had no real need to determine proper initial velocities, because orbits didn't decay the same way. With the correct mathematics in place, however, I had trouble keeping my planets from dying en masse, so I looked up the Centripetal Acceleration equation and reversed it to get the correct velocity for a given acceleration. That in hand, the Velocity Constant became a scalar instead of an absolute value: v=2 is twice the 'correct' initial velocity, etc.

* Solar Flares
Solar flares take advantage of 'killed' planets--specifically, the fact that they are no longer in the fixed-size planet array--by ejecting point masses from the sun's surface, at odd angles and at some scalar fv of the escape velocity of the sun

* Compatability, The Sources, and Compiling
From Grfxgrav-1.0 to the time of this release, and probably into the future, I have used the following to create my project: Qt 3.1.2, KDE 3.1.3, KDevelop 2.1.5, GNU automake 1.4-p6, Autoconf 2.13, as distributed with Mandrake Linux 9.2. There is at least one reported instance of an issue with compiling the code because of problems with autoconf and automake, and that is why I have released binaries, although I do not know to what extent they will be compatable, either. The problem is that I do not have sufficient internet access to download everything I would need to bring the project up to date: newer versions of automake and autoconf don't seem to work with KDevelop, and downloading a new KDevelop would require more time and/or bandwidth than I have available. Therefore I must apologize to anyone who is inconvenienced, but there isn't anything I can do right now.