MattTheTekie/devilutionX
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Clean up FindPath.

Browse source
This commit is contained in:
Sergey Semushin 2019-06-02 21:15:50 +03:00 • committed by Anders Jenbo
commit c5c7bb8a44
1 changed files with 19 additions and 44 deletions
Download patch file Download diff file Expand all files Collapse all files

63
Source/path.cpp
View file

@ -40,36 +40,23 @@ char path_directions[9] = { 5, 1, 6, 2, 0, 3, 8, 4, 7 };
*/
int FindPath(BOOL(*PosOk)(int, int, int), int PosOkArg, int sx, int sy, int dx, int dy, char *path)
{
PATHNODE *path_start; // esi
char initial_h; // al
PATHNODE *next_node; // eax
int result; // eax
PATHNODE *current; // edx
PATHNODE **previous; // eax
int path_length; // edi
BOOLEAN path_is_full; // zf
int *step_ptr; // ecx
char step; // dl
PATHNODE *path_start, *next_node, *current;
int path_length, i;
// clear all nodes, create root nodes for the visited/frontier linked lists
gdwCurNodes = 0;
path_2_nodes = path_new_step();
gdwCurPathStep = 0;
pnode_ptr = path_new_step();
gdwCurPathStep = 0;
path_start = path_new_step();
path_start->g = 0;
initial_h = path_get_h_cost(sx, sy, dx, dy);
path_start->h = initial_h;
path_start->h = path_get_h_cost(sx, sy, dx, dy);
path_start->x = sx;
path_start->f = initial_h + path_start->g;
path_start->f = path_start->h + path_start->g;
path_start->y = sy;
path_2_nodes->NextNode = path_start;
// A* search until we find (dx,dy) or fail
while (TRUE) {
next_node = GetNextPath();
// frontier is empty, no path!
if (!next_node)
return 0;
while ((next_node = GetNextPath())) {
// reached the end, success!
if (next_node->x == dx && next_node->y == dy)
break;
@ -77,35 +64,23 @@ int FindPath(BOOL(*PosOk)(int, int, int), int PosOkArg, int sx, int sy, int dx,
if (!path_get_path(PosOk, PosOkArg, next_node, dx, dy))
return 0;
}
// frontier is empty, no path!
if (!next_node)
return 0;
current = next_node;
previous = &next_node->Parent;
path_length = 0;
if (*previous) {
while (TRUE) {
path_is_full = path_length == 25;
if (path_length >= 25)
break;
pnode_vals[++path_length - 1] = path_directions[3 * (current->y - (*previous)->y) - (*previous)->x + 4 + current->x];
current = *previous;
previous = &(*previous)->Parent;
if (!*previous) {
path_is_full = path_length == 25;
break;
}
}
if (path_is_full)
return 0;
while (current->Parent) {
if (path_length >= 25)
break;
pnode_vals[path_length++] = path_directions[3 * (current->y - current->Parent->y) - current->Parent->x + 4 + current->x];
current = current->Parent;
}
result = 0;
if (path_length > 0) {
step_ptr = &pnode_vals[path_length - 1];
do {
step = *(_BYTE *)step_ptr;
--step_ptr;
path[result++] = step;
} while (result < path_length);
if (path_length != 25) {
for (i = 0; i < path_length; i++)
path[i] = pnode_vals[path_length - i - 1];
return i;
}
return result;
return 0;
}
/* heuristic, estimated cost from (sx,sy) to (dx,dy) */