code/__DEFINES/maths.dm
| SIGN | Gets the sign of x, returns -1 if negative, 0 if 0, 1 if positive |
|---|---|
| WRAP_UP | Increments a value and wraps it if it exceeds some value. Can be used to circularly iterate through a list through idx = WRAP_UP(idx, length_of_list). |
| LPFILTER | Low-pass filter a value to smooth out high frequent peaks. This can be thought of as a moving average filter as well. delta_time is how many seconds since we last ran this command. RC is the filter constant, high RC means more smoothing See https://en.wikipedia.org/wiki/Low-pass_filter#Simple_infinite_impulse_response_filter for the maths |
| TOBITSHIFT | Gets shift x that would be required the bitflag (1<<x) We need the round because log has floating-point inaccuracy, and if we undershoot at all on list indexing we'll get the wrong index. |
| DT_PROB_RATE | Converts a probability/second chance to probability/delta_time chance
For example, if you want an event to happen with a 10% per second chance, but your proc only runs every 5 seconds, do if(prob(100*DT_PROB_RATE(0.1, 5))) |
| DT_PROB | Like DT_PROB_RATE but easier to use, simply put if(DT_PROB(10, 5)) |
| MANHATTAN_DISTANCE | Taxicab distance--gets you the actual time it takes to get from one turf to another due to how we calculate diagonal movement |
| LOGISTIC_FUNCTION | A function that exponentially approaches a maximum value of L k is the rate at which is approaches L, x_0 is the point where the function = 0 |
| FORCE_BOOLEAN | Make sure something is a boolean TRUE/FALSE 1/0 value, since things like bitfield & bitflag doesn't always give 1s and 0s. |
| TILES_TO_PIXELS | Gives the number of pixels in an orthogonal line of tiles. |
| DIAMOND_AREA | The number of cells in a taxicab circle (rasterized diamond) of radius X. |
Define Details
DIAMOND_AREA
The number of cells in a taxicab circle (rasterized diamond) of radius X.
DT_PROB
Like DT_PROB_RATE but easier to use, simply put if(DT_PROB(10, 5))
DT_PROB_RATE
Converts a probability/second chance to probability/delta_time chance
For example, if you want an event to happen with a 10% per second chance, but your proc only runs every 5 seconds, do if(prob(100*DT_PROB_RATE(0.1, 5)))
FORCE_BOOLEAN
Make sure something is a boolean TRUE/FALSE 1/0 value, since things like bitfield & bitflag doesn't always give 1s and 0s.
LOGISTIC_FUNCTION
A function that exponentially approaches a maximum value of L k is the rate at which is approaches L, x_0 is the point where the function = 0
LPFILTER
Low-pass filter a value to smooth out high frequent peaks. This can be thought of as a moving average filter as well. delta_time is how many seconds since we last ran this command. RC is the filter constant, high RC means more smoothing See https://en.wikipedia.org/wiki/Low-pass_filter#Simple_infinite_impulse_response_filter for the maths
MANHATTAN_DISTANCE
Taxicab distance--gets you the actual time it takes to get from one turf to another due to how we calculate diagonal movement
SIGN
Gets the sign of x, returns -1 if negative, 0 if 0, 1 if positive
TILES_TO_PIXELS
Gives the number of pixels in an orthogonal line of tiles.
TOBITSHIFT
Gets shift x that would be required the bitflag (1<<x) We need the round because log has floating-point inaccuracy, and if we undershoot at all on list indexing we'll get the wrong index.
WRAP_UP
Increments a value and wraps it if it exceeds some value. Can be used to circularly iterate through a list through idx = WRAP_UP(idx, length_of_list).