bool AIHasClearShot(const Vec2i from, const Vec2i to)
{
// Perform 4 line tests - above, below, left and right
// This is to account for possible positions for the muzzle
Vec2i fromOffset = from;
const int pad = 2;
fromOffset.x = from.x - (ACTOR_W + pad) / 2;
if (Vec2iToTile(fromOffset).x >= 0 &&
!AIHasClearLine(fromOffset, to, IsPosNoSee))
{
return false;
}
fromOffset.x = from.x + (ACTOR_W + pad) / 2;
if (Vec2iToTile(fromOffset).x < gMap.Size.x &&
!AIHasClearLine(fromOffset, to, IsPosNoSee))
{
return false;
}
fromOffset.x = from.x;
fromOffset.y = from.y - (ACTOR_H + pad) / 2;
if (Vec2iToTile(fromOffset).y >= 0 &&
!AIHasClearLine(fromOffset, to, IsPosNoSee))
{
return false;
}
fromOffset.y = from.y + (ACTOR_H + pad) / 2;
if (Vec2iToTile(fromOffset).y < gMap.Size.y &&
!AIHasClearLine(fromOffset, to, IsPosNoSee))
{
return false;
}
return true;
}
int AIGoto(TActor *actor, Vec2i p, bool ignoreObjects)
{
Vec2i a = Vec2iFull2Real(actor->Pos);
Vec2i currentTile = Vec2iToTile(a);
Vec2i goalTile = Vec2iToTile(p);
AIGotoContext *c = &actor->aiContext->Goto;
// If we are already there, bail
// This can happen if AI is trying to track the player,
// but the player has died, for example.
if (Vec2iEqual(currentTile, goalTile))
{
return 0;
}
// If we are currently following an A* path,
// and it is still valid, keep following it until
// we have reached a new tile
if (c && c->IsFollowing && AStarCloseToPath(c, currentTile, goalTile))
{
return AStarFollow(c, currentTile, &actor->tileItem, a);
}
else if (AIHasClearPath(a, p, ignoreObjects))
{
// Simple case: if there's a clear line between AI and target,
// walk straight towards it
return AIGotoDirect(a, p);
}
else
{
// We need to recalculate A*
AStarContext ac;
ac.Map = &gMap;
ac.IsTileOk =
ignoreObjects ? IsTileWalkable : IsTileWalkableAroundObjects;
// First, if the goal tile is blocked itself,
// find a nearby tile that can be walked to
c->Goal = MapSearchTileAround(ac.Map, goalTile, ac.IsTileOk);
c->PathIndex = 1; // start navigating to the next path node
ASPathDestroy(c->Path);
c->Path = ASPathCreate(
&cPathNodeSource, &ac, ¤tTile, &c->Goal);
// In case we can't calculate A* for some reason,
// try simple navigation again
if (ASPathGetCount(c->Path) <= 1)
{
debug(
D_MAX,
"Error: can't calculate path from {%d, %d} to {%d, %d}",
currentTile.x, currentTile.y,
goalTile.x, goalTile.y);
return AIGotoDirect(a, p);
}
return AStarFollow(c, currentTile, &actor->tileItem, a);
}
}
void CollideAllItems(
const TTileItem *item, const Vec2i pos,
const int mask, const CollisionTeam team, const bool isPVP,
CollideItemFunc func, void *data)
{
const Vec2i tv = Vec2iToTile(pos);
Vec2i dv;
// Check collisions with all other items on this tile, in all 8 directions
for (dv.y = -1; dv.y <= 1; dv.y++)
{
for (dv.x = -1; dv.x <= 1; dv.x++)
{
const Vec2i dtv = Vec2iAdd(tv, dv);
if (!MapIsTileIn(&gMap, dtv))
{
continue;
}
CArray *tileThings = &MapGetTile(&gMap, dtv)->things;
for (int i = 0; i < (int)tileThings->size; i++)
{
TTileItem *ti = ThingIdGetTileItem(CArrayGet(tileThings, i));
// Don't collide if items are on the same team
if (!CollisionIsOnSameTeam(ti, team, isPVP))
{
if (item != ti &&
(ti->flags & mask) &&
ItemsCollide(item, ti, pos))
{
func(ti, data);
}
}
}
}
}
}
TTileItem *GetItemOnTileInCollision(
TTileItem *item, Vec2i pos, int mask, CollisionTeam team, int isDogfight)
{
Vec2i tv = Vec2iToTile(pos);
Vec2i dv;
if (!MapIsTileIn(&gMap, tv))
{
return NULL;
}
// Check collisions with all other items on this tile, in all 8 directions
for (dv.y = -1; dv.y <= 1; dv.y++)
{
for (dv.x = -1; dv.x <= 1; dv.x++)
{
CArray *tileThings = &MapGetTile(&gMap, Vec2iAdd(tv, dv))->things;
for (int i = 0; i < (int)tileThings->size; i++)
{
TTileItem *ti = ThingIdGetTileItem(CArrayGet(tileThings, i));
// Don't collide if items are on the same team
if (!CollisionIsOnSameTeam(ti, team, isDogfight))
{
if (item != ti &&
(ti->flags & mask) &&
ItemsCollide(item, ti, pos))
{
return ti;
}
}
}
}
}
return NULL;
}
// Use pathfinding to check that there is a path between
// source and destination tiles
bool AIHasPath(const Vec2i from, const Vec2i to, const bool ignoreObjects)
{
// Quick first test: check there is a clear path
if (AIHasClearPath(from, to, ignoreObjects))
{
return true;
}
// Pathfind
AStarContext ac;
ac.Map = &gMap;
ac.IsTileOk = ignoreObjects ? IsTileWalkable : IsTileWalkableAroundObjects;
Vec2i fromTile = Vec2iToTile(from);
Vec2i toTile = MapSearchTileAround(ac.Map, Vec2iToTile(to), ac.IsTileOk);
ASPath path = ASPathCreate(&cPathNodeSource, &ac, &fromTile, &toTile);
size_t pathCount = ASPathGetCount(path);
ASPathDestroy(path);
return pathCount > 1;
}
static bool TryPlacePickup(HealthPickups *h)
{
Vec2i size = Vec2iNew(HEALTH_W, HEALTH_H);
// Attempt to place one in unexplored area
for (int i = 0; i < 100; i++)
{
const Vec2i v = MapGenerateFreePosition(h->map, size);
if (!Vec2iIsZero(v) && !MapGetTile(h->map, Vec2iToTile(v))->isVisited)
{
MapPlaceHealth(v);
return true;
}
}
// Attempt to place one in out-of-sight area
for (int i = 0; i < 100; i++)
{
const Vec2i v = MapGenerateFreePosition(h->map, size);
const Vec2i fullpos = Vec2iReal2Full(v);
const TActor *closestPlayer = AIGetClosestPlayer(fullpos);
if (!Vec2iIsZero(v) &&
(!closestPlayer || CHEBYSHEV_DISTANCE(
fullpos.x, fullpos.y,
closestPlayer->Pos.x, closestPlayer->Pos.y) >= 256 * 150))
{
MapPlaceHealth(v);
return true;
}
}
// Attempt to place one anyway
for (int i = 0; i < 100; i++)
{
const Vec2i v = MapGenerateFreePosition(h->map, size);
if (!Vec2iIsZero(v))
{
MapPlaceHealth(v);
return true;
}
}
return false;
}
static bool IsPosNoSee(void *data, Vec2i pos)
{
return MapGetTile(data, Vec2iToTile(pos))->flags & MAPTILE_NO_SEE;
}
static bool IsPosNoWalkAroundObjects(void *data, Vec2i pos)
{
return !IsTileWalkableAroundObjects(data, Vec2iToTile(pos));
}
static bool IsPosNoWalk(void *data, Vec2i pos)
{
return !IsTileWalkable(data, Vec2iToTile(pos));
}
static bool IsPosNoSee(void *data, Vec2i pos)
{
const Tile *t = MapGetTile(data, Vec2iToTile(pos));
return t != NULL && (t->flags & MAPTILE_NO_SEE);
}
bool UpdateBullet(TMobileObject *obj, const int ticks)
{
obj->count += ticks;
obj->soundLock = MAX(0, obj->soundLock - ticks);
obj->specialLock = MAX(0, obj->specialLock - ticks);
if (obj->count < obj->bulletClass->Delay)
{
return true;
}
if (obj->range >= 0 && obj->count > obj->range)
{
if (!gCampaign.IsClient)
{
FireGuns(obj, &obj->bulletClass->OutOfRangeGuns);
}
return false;
}
const Vec2i objPos = Vec2iNew(obj->x, obj->y);
if (obj->bulletClass->SeekFactor > 0)
{
// Find the closest target to this bullet and steer towards it
const TActor *owner = ActorGetByUID(obj->ActorUID);
if (owner == NULL)
{
return false;
}
const TActor *target = AIGetClosestEnemy(objPos, owner, obj->flags);
if (target && !target->dead)
{
for (int i = 0; i < ticks; i++)
{
obj->vel = SeekTowards(
objPos, obj->vel,
obj->bulletClass->SpeedLow, target->Pos,
obj->bulletClass->SeekFactor);
}
}
}
Vec2i pos = Vec2iScale(Vec2iAdd(objPos, obj->vel), ticks);
HitType hitItem = HIT_NONE;
if (!gCampaign.IsClient)
{
hitItem = HitItem(obj, pos, obj->bulletClass->Persists);
}
const Vec2i realPos = Vec2iFull2Real(pos);
// Falling (grenades)
if (obj->bulletClass->Falling.GravityFactor != 0)
{
bool hasDropped = obj->z <= 0;
for (int i = 0; i < ticks; i++)
{
obj->z += obj->dz;
if (obj->z <= 0)
{
obj->z = 0;
if (obj->bulletClass->Falling.Bounces)
{
obj->dz = -obj->dz / 2;
}
else
{
obj->dz = 0;
}
if (!hasDropped)
{
if (!gCampaign.IsClient)
{
FireGuns(obj, &obj->bulletClass->Falling.DropGuns);
}
}
hasDropped = true;
if (obj->bulletClass->Falling.DestroyOnDrop)
{
return false;
}
SoundPlayAt(
&gSoundDevice,
StrSound(obj->bulletClass->HitSound.Wall), realPos);
}
else
{
obj->dz -= obj->bulletClass->Falling.GravityFactor;
}
if (!obj->bulletClass->Falling.FallsDown)
{
obj->dz = MAX(0, obj->dz);
}
}
}
// Friction
const bool isDiagonal = obj->vel.x != 0 && obj->vel.y != 0;
int frictionComponent = isDiagonal ?
(int)round(obj->bulletClass->Friction / sqrt(2)) :
obj->bulletClass->Friction;
for (int i = 0; i < ticks; i++)
{
if (obj->vel.x > 0)
{
obj->vel.x -= frictionComponent;
}
else if (obj->vel.x < 0)
{
obj->vel.x += frictionComponent;
}
if (obj->vel.y > 0)
{
obj->vel.y -= frictionComponent;
}
else if (obj->vel.y < 0)
{
obj->vel.y += frictionComponent;
}
}
bool hitWall = false;
if (!gCampaign.IsClient && hitItem == HIT_NONE)
{
hitWall =
MapIsRealPosIn(&gMap, realPos) && ShootWall(realPos.x, realPos.y);
}
if (hitWall || hitItem != HIT_NONE)
{
GameEvent b = GameEventNew(GAME_EVENT_BULLET_BOUNCE);
b.u.BulletBounce.UID = obj->UID;
if (hitWall && !Vec2iIsZero(obj->vel))
{
b.u.BulletBounce.HitType = (int)HIT_WALL;
}
else
{
b.u.BulletBounce.HitType = (int)hitItem;
}
bool alive = true;
if ((hitWall && !obj->bulletClass->WallBounces) ||
((hitItem != HIT_NONE) && obj->bulletClass->HitsObjects))
{
b.u.BulletBounce.Spark = true;
CASSERT(!gCampaign.IsClient, "Cannot process bounces as client");
FireGuns(obj, &obj->bulletClass->HitGuns);
if (hitWall || !obj->bulletClass->Persists)
{
alive = false;
}
}
b.u.BulletBounce.BouncePos = Vec2i2Net(pos);
b.u.BulletBounce.BounceVel = Vec2i2Net(obj->vel);
if (hitWall && !Vec2iIsZero(obj->vel))
{
// Bouncing
Vec2i bounceVel = obj->vel;
pos = GetWallBounceFullPos(objPos, pos, &bounceVel);
b.u.BulletBounce.BouncePos = Vec2i2Net(pos);
b.u.BulletBounce.BounceVel = Vec2i2Net(bounceVel);
obj->vel = bounceVel;
}
GameEventsEnqueue(&gGameEvents, b);
if (!alive)
{
return false;
}
}
if (!MapTryMoveTileItem(&gMap, &obj->tileItem, realPos))
{
obj->count = obj->range;
return false;
}
obj->x = pos.x;
obj->y = pos.y;
if (obj->bulletClass->Erratic)
{
for (int i = 0; i < ticks; i++)
{
obj->vel.x += ((rand() % 3) - 1) * 128;
obj->vel.y += ((rand() % 3) - 1) * 128;
}
}
// Proximity function, destroy
// Only check proximity every now and then
if (obj->bulletClass->ProximityGuns.size > 0 && !(obj->count & 3))
{
if (!gCampaign.IsClient)
{
// Detonate the mine if there are characters in the tiles around it
const Vec2i tv =
Vec2iToTile(Vec2iFull2Real(pos));
Vec2i dv;
for (dv.y = -1; dv.y <= 1; dv.y++)
{
for (dv.x = -1; dv.x <= 1; dv.x++)
{
const Vec2i dtv = Vec2iAdd(tv, dv);
if (!MapIsTileIn(&gMap, dtv))
{
continue;
}
if (TileHasCharacter(MapGetTile(&gMap, dtv)))
{
FireGuns(obj, &obj->bulletClass->ProximityGuns);
return false;
}
}
}
}
}
return true;
}
