Core RTS: Path finding seems to work!

build/rtsgame/map.core

@@ -1,24 +1,86 @@
 
 MAP_CurrentMap: MAP_Map
-
+MAP_OpenPaths: Array(MAP_Path)
+MAP_ClosePaths: Array(MAP_Path)
+MAP_History: Array(MAP_Path)
+MAP_TargetP: V2I
+MAP_StartP: V2I
+MAP_ReachedTarget := false
 
 MAP_Tile :: int
 MAP_Map :: struct
   data: *MAP_Tile
   x: int
   y: int
-  actors: Array(Actor)
+  actors: Array(MAP_Actor)
 
-Actor :: struct
+MAP_Actor :: struct
   p: V2I
   target_p: V2I
 
+MAP_Path :: struct
+  value_to_sort_by: int // distance from target
+  p: V2I
+  came_from: V2I
 
 MAP_Init :: ()
-  MAP_X :: 60
-  MAP_Y :: 40
-
-  map_data: [MAP_X*MAP_Y]int
-  MAP_CurrentMap = MAP_Map{data = &map_data[0], x = MAP_X, y = MAP_Y}
+  MAP_CurrentMap.x = 60
+  MAP_CurrentMap.y = 40
+  MAP_CurrentMap.data = malloc(SizeOf(MAP_Tile) * MAP_CurrentMap.x->U64 * MAP_CurrentMap.y->U64)
   Add(&MAP_CurrentMap.actors, {{4, 4}, {8, 8}})
 
+MAP_InsertOpenPath :: (p: V2I, target_p: V2I, came_from: V2I)
+  if p.x < 0 || p.x >= MAP_CurrentMap.x ;; return
+  if p.y < 0 || p.y >= MAP_CurrentMap.y ;; return
+  if MAP_CurrentMap.data[p.x + p.y * MAP_CurrentMap.x] == 1 ;; return
+
+  for i := 0, i < MAP_ClosePaths.len, i += 1
+    it := MAP_ClosePaths.data + i
+    if it.p.x == p.x && it.p.y == p.y ;; return
+
+  for i := 0, i < MAP_OpenPaths.len, i += 1
+    it := MAP_OpenPaths.data + i
+    if it.p.x == p.x && it.p.y == p.y ;; return
+
+
+  dx := target_p.x - p.x
+  dy := target_p.y - p.y
+  d  := dx*dx + dy*dy
+  InsertSortedDecreasing(&MAP_OpenPaths, {d, p, came_from})
+
+MAP_PathFindStart :: (actor: *MAP_Actor)
+  Reset(&MAP_OpenPaths)
+  Reset(&MAP_ClosePaths)
+  MAP_TargetP = actor.target_p
+  MAP_StartP = actor.p
+  MAP_InsertOpenPath(actor.p, actor.target_p, actor.p)
+
+MAP_GetCloseP :: (p: V2I): *MAP_Path
+  for i := 0, i < MAP_ClosePaths.len, i += 1
+    it := MAP_ClosePaths.data + i
+    if it.p.x == p.x && it.p.y == p.y ;; return it
+
+  Assert(false)
+  return 0
+
+MAP_PathFindStep :: ()
+  if MAP_ReachedTarget ;; return
+
+  it := Pop(&MAP_OpenPaths)
+  Add(&MAP_ClosePaths, it)
+
+  MAP_ReachedTarget = it.p.x == MAP_TargetP.x && it.p.y == MAP_TargetP.y
+  if MAP_ReachedTarget
+    Add(&MAP_History, it)
+    for !(it.p.x == MAP_StartP.x && it.p.y == MAP_StartP.y)
+      it = *MAP_GetCloseP(it.came_from)
+      Add(&MAP_History, it)
+    return
+
+  // @language_todo: Add continue keyword
+  // if x == 0 && y == 0 ;; continue
+  for y := -1, y <= 1, y += 1
+    for x := -1, x <= 1, x += 1
+      if (x == 0 && y == 0) == false
+        p := V2I{it.p.x + x, it.p.y + y}
+        MAP_InsertOpenPath(p, MAP_TargetP, it.p)