Simone

Re: How do you find planets?

Thu Aug 20, 2015 17:21

79.41.74.115

Of course, in school you learn 2D Cartesian coordinates as X and Y... but then, when you plot a 2D graph on a screen, the Y coordinate is vertical. ;-) So, when you need an extra dimension, you use Z.

Anyway, the real coordinates are used to allow the use of integers when dealing with moon coordinates, and most important, when dealing with the movement of Damocles, which otherwise would require the use of floats.

Real celestial bodies move along conic sections (ellipses, parabolas, hyperbolas) but plotting such curves on an Atari ST cannot be done in real time. For this reason, the trajectory of Damocles is defined by a series of points (each of which has integer coordinates), and Damocles moves following straight segments from one point to another, which are much faster to compute with a 7 MHz CPU.

Anyway, the real coordinates are used to allow the use of integers when dealing with moon coordinates, and most important, when dealing with the movement of Damocles, which otherwise would require the use of floats.

Real celestial bodies move along conic sections (ellipses, parabolas, hyperbolas) but plotting such curves on an Atari ST cannot be done in real time. For this reason, the trajectory of Damocles is defined by a series of points (each of which has integer coordinates), and Damocles moves following straight segments from one point to another, which are much faster to compute with a 7 MHz CPU.

- Re: How do you find planets? — Anonymous, Thu Aug 20 13:23Thanks. Oh, the main reason I think of the coords in that way is that everything in Damocles is pretty much flat. We learn that on flat 2D graph paper you have x & y coords. You have flat cities (X-Y ... more
- Re: How do you find planets? — Simone, Thu Aug 20 17:21