/**
* Can we see this location?
*
* @param mapX
* @param mapY
* @param positive If non null, if this entity is detected, algorithm returns true
* @param targetFlying If true, and positive is a flying gidrah, we ignore walls and simply return
* true
* @return true if there is a LOS to the specified map location
*/
public boolean canSee(float mapX, float mapY, Entity positive, boolean targetFlying) {
if (targetFlying && positive != null && positive.isFlying()) {
return true;
}
WormGameState gameState = Worm.getGameState();
GameMap map = gameState.getMap();
ArrayList<Entity> entities = gameState.getEntities();
int n = entities.size();
// Create a list of solid entities we think are somewhere in the LOS
ENTITYCACHE.clear();
for (int i = 0; i < n; i++) {
Entity e = entities.get(i);
if (e != this && e.isActive() && e.isSolid()) {
double dist = Util.distanceFromLineToPoint(getX(), getY(), mapX, mapY, e.getX(), e.getY());
if (dist >= 0.0 && dist <= e.getRadius()) {
ENTITYCACHE.add(e);
}
}
}
int numCachedEntities = ENTITYCACHE.size();
BRESENHAM.plot((int) getX(), (int) getY(), (int) mapX, (int) mapY);
int oldMapX = -1, oldMapY = -1;
while (BRESENHAM.next()) {
int x = BRESENHAM.getX() / MapRenderer.TILE_SIZE;
int y = BRESENHAM.getY() / MapRenderer.TILE_SIZE;
if (x != oldMapX || y != oldMapY) {
for (int z = 0; z < GameMap.LAYERS; z++) {
Tile tile = map.getTile(x, y, z);
if (tile != null && !tile.isBulletThrough()) {
// Tile blocks LOS
return false;
}
}
oldMapX = x;
oldMapY = y;
}
// Check entity list
if (positive != null) {
for (int i = 0; i < numCachedEntities; i++) {
Entity e = ENTITYCACHE.get(i);
if (e == positive
&& e.getDistanceTo(BRESENHAM.getX(), BRESENHAM.getY()) < e.getRadius()) {
return true;
}
}
}
// Skip 4 pixels at a time
if (!BRESENHAM.next()) {
break;
}
if (!BRESENHAM.next()) {
break;
}
if (!BRESENHAM.next()) {
break;
}
}
return true;
}
/**
* Get the distance to another entity
*
* @param xx
* @param yy
* @return distance, in pixels
*/
public float getDistanceTo(Entity e) {
return Vector2f.sub(new Vector2f(e.getX(), e.getY()), new Vector2f(getX(), getY()), null)
.length();
}