Fix bug:7454

* Official Icewall implementation and other fixes
- Reverted all the icewall-related changes done in SVN r15777 and following as testing shows they aren't official and are actually pretty exploitable (bugreport:7412)
- Instead implemented the official icewall characteristic that monsters can only leave an icewall cell to the west or south, the changes include:
  * The "sight" path check no longer checks for the current cell so standing on an icewall allows you to see/attack into any direction
  * The path finding will still ignore the current cell as before but the walk routine will not allow to walk east or north while standing on an icewall cell
  * This leads monsters in the situation where they go through an AI loop not allowing them to escape the icewall (if their target is north or east of them)
  * Monster in this situation will use idle skills and if they get attacked will use their rudeattacked skills if available, similar to traps like Spiderweb
  * Added a configuration icewall_walk_block that allows to configure how long a monster should go through the AI loop before the server allows it any movement, this "safety" system is official and seems to equal about 75 AI loops; if you want to disable the whole icewall system so that monsters don't get stuck in icewall at all, just set this to 0
  * Here are videos from jRO showing how this system works: http://ragdo.blog56.fc2.com/blog-entry-763.html
- Implemented the official calculation for "direction"; now you will be considered horizontal/vertical/diagonally aligned with a target cell in the exact same way as on official servers, this is for example used to determine whether an icewall or a firewall should be horizontal, vertical or diagonal; the only thing that is still unofficial is the default direction (officially always "west"); effectively now there are more situations considered diagonal than before
- Further cleanups on the idle skill use code for immobile monsters and monsters near a player but without a target (now skill using will always go via mob_unlocktarget)
  * This also fixes that monsters switched to idle mode and start to use idle skills one second too late

Mega thanks to Playtester (rathena 5540d89cb0e)

1 files changed, 2 insertions, 5 deletions

diff --git a/src/map/path.c b/src/map/path.c
index 681dfcb06..d8096ad43 100644
--- a/src/map/path.c
+++ b/src/map/path.c
@@ -129,9 +129,6 @@ bool path_search_long(struct shootpath_data *spd,int16 m,int16 x0,int16 y0,int16
 	spd->x[0] = x0;
 	spd->y[0] = y0;
 
-	if (md->getcellp(md,x1,y1,cell))
-		return false;
-
 	if (dx > abs(dy)) {
 		weight = dx;
 		spd->ry = 1;
@@ -142,8 +139,6 @@ bool path_search_long(struct shootpath_data *spd,int16 m,int16 x0,int16 y0,int16
 
 	while (x0 != x1 || y0 != y1)
 	{
-		if (md->getcellp(md,x0,y0,cell))
-			return false;
 		wx += dx;
 		wy += dy;
 		if (wx >= weight) {
@@ -163,6 +158,8 @@ bool path_search_long(struct shootpath_data *spd,int16 m,int16 x0,int16 y0,int16
 			spd->y[spd->len] = y0;
 			spd->len++;
 		}
+		if (md->getcellp(md,x0,y0,cell))
+			return false;
 	}
 
 	return true;