/
sssp.dm
300 lines (268 loc) · 11.7 KB
/
sssp.dm
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
#define FLOW_PATH_END 1
/// Datum that describes the shortest path between a source turf and any turfs within a distance
/datum/path_map
/// Assoc list of turf -> the turf one step closer on the path
/// Arranged in discovery order, so the last turf here will be the furthest from the start
var/list/next_closest = list()
/// List of distances from the starting turf, each index lines up with the next_closest list
var/list/distances = list()
/// Our starting turf, the location this map feeds into
var/turf/start
/// The tick we were completed on, in case you want to hold onto this for a bit
var/creation_time
/// The pass info datum used to create us
var/datum/can_pass_info/pass_info
/// Were we allowed to path over space?
var/pass_space = TRUE
/// Were we avoiding a turf? If so, which one?
var/turf/avoid
/// Are we currently being expanded?
var/expanding = FALSE
/// Are we currently being built
var/building = FALSE
/// Gets a list of turfs reachable by this path_map from the distance first to the distance second, both inclusive
/// first > second or first < second are both respected, and the return order will reflect the arg order
/// We return a list of turf -> distance, or null if we error
/datum/path_map/proc/turfs_in_range(first, second)
var/list/hand_back = list()
var/list/distances = src.distances
var/smaller = min(first, second)
var/larger = max(first, second)
var/largest_dist = distances[length(distances)]
if(smaller < 0 || larger < 0 || largest_dist < larger || largest_dist < smaller)
return null
if(first == smaller)
for(var/i in 1 to length(distances))
if(i > larger)
break
if(i >= smaller)
hand_back[next_closest[i]] = distances[i]
else
for(var/i in length(distances) to 1 step -1)
if(i < smaller)
break
if(i <= larger)
hand_back[next_closest[i]] = distances[i]
return hand_back
/**
* Takes a turf to path to, returns the shortest path to it at the time of this datum's creation
*
* skip_first - If we should drop the first step in the path. Used to avoid stepping where we already are
* min_target_dist - How many, if any, turfs off the end of the path should we drop?
*/
/datum/path_map/proc/get_path_to(turf/path_to, skip_first = FALSE, min_target_dist = 0)
return generate_path(path_to, skip_first, min_target_dist)
/**
* Takes a turf to start from, returns a path to the source turf of this datum
*
* skip_first - If we should drop the first step in the path. Used to avoid stepping where we already are
* min_target_dist - How many, if any, turfs off the end of the path should we drop?
*/
/datum/path_map/proc/get_path_from(turf/path_from, skip_first = FALSE, min_target_dist = 0)
return generate_path(path_from, skip_first, min_target_dist, reverse = TRUE)
/**
* Takes a turf to use as the other end, returns the path between the source node and it
*
* skip_first - If we should drop the first step in the path. Used to avoid stepping where we already are
* min_target_dist - How many, if any, turfs off the end of the path should we drop?
* reverse - If true, "reverses" the path generated. You'd want to use this for generating a path to the source node itself
*/
/datum/path_map/proc/generate_path(turf/other_end, skip_first = FALSE, min_target_dist = 0, reverse = FALSE)
var/list/path = list()
var/turf/next_turf = other_end
// Cache for sonic speed
var/next_closest = src.next_closest
while(next_turf != FLOW_PATH_END || next_turf == null)
path += next_turf
next_turf = next_closest[next_turf] // We take the first entry cause that's the turf
// This makes sense from a consumer level, I hate double negatives too I promise
if(!reverse)
path = reverseList(path)
if(skip_first && length(path) > 0)
path.Cut(1,2)
if(min_target_dist)
path.Cut(length(path) + 1 - min_target_dist, length(path) + 1)
return path
/datum/path_map/proc/display(delay = 10 SECONDS)
for(var/index in 1 to length(distances))
var/turf/next_turf = next_closest[index]
next_turf.maptext = "[distances[index]]"
next_turf.color = COLOR_NAVY
animate(next_turf, color = null, delay)
animate(maptext = "", world.tick_lag)
/// Copies the passed in path_map into this datum
/// Saves some headache with updating refs if we want to modify a path_map
/datum/path_map/proc/copy_from(datum/path_map/read_from)
// Copy all the relevant vars over. NOT any of the timer stuff, we want them to still count
src.next_closest = read_from.next_closest
src.distances = read_from.distances
src.start = read_from.start
src.pass_info = read_from.pass_info
src.pass_space = read_from.pass_space
src.avoid = read_from.avoid
/// Returns true if the passed in pass_map's pass logic matches ours
/// False otherwise
/datum/path_map/proc/compare_against(datum/path_map/map)
return compare_against_args(map.pass_info, map.start, map.pass_space, map.avoid)
/// Returns true if the passed in pass_info and start/pass_space/avoid match ours
/// False otherwise
/datum/path_map/proc/compare_against_args(datum/can_pass_info/pass_info, turf/start, pass_space, turf/avoid)
if(src.start != start)
return FALSE
if(src.pass_space != pass_space)
return FALSE
if(src.avoid != avoid)
return FALSE
return pass_info.compare_against(pass_info)
/// Returns a new /datum/pathfind/sssp based off our settings
/// Will have an invalid source mob, no max distance, and no ending callback
/datum/path_map/proc/settings_to_path()
// Default creation to not set any vars incidentially
var/static/mob/jeremy = new()
var/datum/pathfind/sssp/based_on_what = new()
based_on_what.setup(pass_info, null, INFINITY, pass_space, avoid)
return based_on_what
/// Expands this pathmap to cover a new range, assuming the arg is greater then the current range
/// Returns true if this succeeded or was not required, false otherwise
/datum/path_map/proc/expand(new_range)
var/list/working_distances = distances
var/working_index = working_distances.len
var/max_dist = working_distances[working_distances.len]
if(new_range <= max_dist)
return TRUE
UNTIL(expanding == FALSE)
// In case max_dist has changed ya feel
if(new_range <= max_dist)
return TRUE
// Walk the start point backwards until we're at the first turf at the max distance
while(working_distances[working_index] == max_dist)
working_index -= 1
var/list/hand_around = list()
// We're guarenteed that hand_around will be the first list in pathfinding_finished's argset because of how callback handles the arguments list
var/datum/callback/await = CALLBACK(GLOBAL_PROC, GLOBAL_PROC_REF(pathfinding_finished), hand_around)
// We're gonna build a pathfind datum from our settings and set it running
var/datum/pathfind/sssp/based_off_us = new()
based_off_us.setup_from_canpass(pass_info, start, new_range, pass_space, avoid, list(await))
based_off_us.working_queue = next_closest.Copy()
based_off_us.working_distances = working_distances.Copy()
based_off_us.working_index = working_index
if(!SSpathfinder.run_pathfind(based_off_us))
return FALSE
expanding = TRUE
UNTIL(length(hand_around))
var/datum/path_map/return_val = hand_around[1]
if(!istype(return_val, /datum/path_map)) // It's trash, we've failed and need to clear away
return FALSE
copy_from(return_val)
expanding = FALSE
return TRUE
/datum/path_map/proc/sanity_check()
for(var/index in 1 to length(distances))
var/turf/next_turf = next_closest[index]
var/list/path = get_path_from(next_turf)
if(length(path) != distances[index] + 1)
stack_trace("[next_turf] had a distance of [length(path)] instead of the expected [distances[index]]")
if(path.Find(next_turf) != 1)
stack_trace("Starting turf [next_turf] was not the first entry in its list (instead it's at [path.Find(next_turf)])")
path = get_path_to(next_turf)
if(length(path) != distances[index] + 1)
stack_trace("[next_turf] had a distance of [length(path)] instead of the expected [distances[index]]")
if(path.Find(next_turf) != length(path))
stack_trace("Starting turf [next_turf] was not the last entry in its list (instead it's at [path.Find(next_turf)])")
/// Single source shortest path
/// Generates a flow map of a reachable turf -> the turf next closest to the map's center
/datum/pathfind/sssp
/// Ever expanding list of turfs to visit/visited, associated with the turf that's next closest to them
var/list/working_queue
/// List of distances, each entry mirrors an entry in the working_queue
var/list/working_distances
/// Our current position in the working queue
var/working_index
/datum/pathfind/sssp/proc/setup(atom/movable/caller, list/access, turf/center, max_distance, simulated_only, turf/avoid, list/datum/callback/on_finish)
src.pass_info = new(caller, access)
src.start = center
src.max_distance = max_distance
src.simulated_only = simulated_only
src.avoid = avoid
src.on_finish = on_finish
/datum/pathfind/sssp/proc/setup_from_canpass(datum/can_pass_info/info, turf/center, max_distance, simulated_only, turf/avoid, list/datum/callback/on_finish)
src.pass_info = info
src.start = center
src.max_distance = max_distance
src.simulated_only = simulated_only
src.avoid = avoid
src.on_finish = on_finish
/datum/pathfind/sssp/start()
. = ..()
if(!.)
return .
working_queue = list()
working_distances = list()
working_queue[start] = FLOW_PATH_END
working_distances += 0
working_index = 0
return TRUE
/datum/pathfind/sssp/search_step()
. = ..()
if(!.)
return .
var/datum/can_pass_info/pass_info = src.pass_info
while(working_index < length(working_queue))
working_index += 1
var/turf/next_turf = working_queue[working_index]
var/distance = working_distances[working_index] + 1
if(distance > max_distance)
if(TICK_CHECK)
return TRUE
continue
for(var/turf/adjacent in TURF_NEIGHBORS(next_turf))
// Already have a path? then we're gooood baby
if(working_queue[adjacent])
continue
// If it's blocked, go home
if(!CAN_STEP(next_turf, adjacent, simulated_only, pass_info, avoid))
continue
// I want to prevent diagonal moves around corners
// We do this first because blocked diagonals are more common then non blocked ones.
if(next_turf.x != adjacent.x && next_turf.y != adjacent.y)
var/movement_dir = get_dir(next_turf, adjacent)
// If either of the move components would bump into something, replace it with an explicit move around
var/turf/vertical_move = get_step(next_turf, movement_dir & (NORTH|SOUTH))
var/turf/horizontal_move = get_step(next_turf, movement_dir & (EAST|WEST))
if(!working_queue[vertical_move])
if(CAN_STEP(next_turf, vertical_move, simulated_only, pass_info, avoid))
working_queue[vertical_move] = next_turf
working_distances += distance
else
// Can't do a vertical move? let's do a horizontal move first
if(!working_queue[horizontal_move])
working_queue[horizontal_move] = next_turf
working_distances += distance
continue
if(!working_queue[horizontal_move])
if(CAN_STEP(next_turf, horizontal_move, simulated_only, pass_info, avoid))
working_queue[horizontal_move] = next_turf
working_distances += distance
else
if(!working_queue[vertical_move])
working_queue[vertical_move] = next_turf
working_distances += distance
continue
// Otherwise, this new turf's next closest turf is our source, so we'll mark as such and continue
// This is a breadth first search, we're essentially moving out in layers from the start position
working_queue[adjacent] = next_turf
working_distances += distance
if(TICK_CHECK)
return TRUE
return TRUE
/datum/pathfind/sssp/finished()
var/datum/path_map/flow_map = new()
flow_map.start = start
flow_map.pass_info = pass_info
flow_map.pass_space = simulated_only
flow_map.avoid = avoid
flow_map.next_closest = working_queue
flow_map.distances = working_distances
flow_map.creation_time = world.time
hand_back(flow_map)
return ..()