martinjakubik / planets Goto Github PK

let the user use buttons to navigate back and forth through the saved motion history
depends on storing the history in issue #2

provide a way to turn on playback at a reasonable speed
depends on #2 and #4

adding the G should speed up the simulation when bodies are far apart, but keep manageable when near

putting three bodies at corners with large mass makes two of them annihilate when they collide
they should either pass each other or become one mass
annihilation is a bug

each front end app should use a max of 1Mb for its history file. This should work out to around 300-500 steps in the history.

In v1, just stop at 1Mb.
In v2,
when hit 1Mb, ask user to confirm and overwrite previous entries
always keep the initial position - do not overwrite

let the user download the history of what they just did as a file

when bodies collide, they currently pass through each other.
add a parameter to either:

• continue to allow bodies to pass through each other
• annihilate
• add their mass together and conserve added velocity

add a way (button and keyboard) to clear the grid
make sure all forces are cleared from the data model as well

for example, allow drawing a velocity vector on the body to represent how fast it is currently going

let the user upload a previous history from a file so they can play it back

depends on #16

1. make some planets and move forward to time t
2. return to time t - n
3. change the space (add a new planet or something)

for all time > t - n, all positions should be erased and recalculated

entire page should look attractive
stars should look nice
massive and non-massive stars should look nice
would be nice to have different colours so we could tell stars apart
should be easy to change mass, avoid clicking on wrong "pixel"
should be allowed to change the resolution
buttons, if any, should be integrated in page
controls for navigating in time should be easy to use
navigating in time should be quick, skip ahead easily, but slow for homing in on interesting interactions

at each time t, keep positions of all bodies

for example, all use of left and right arrow keys to navigate back & forth through time

in reality, bodies could always be drawn back to the grid, but to save memory, delete those that have exited the visible area

put three bodies at corners and notice strange behaviour in redraw