Function Script_Structure_FindTargetUnit

src/script/structure.c:303–365

* Find a Unit which is within range and not an ally. * * Stack: 1 - Range to find a target in (amount of tiles multiplied with 256). * * @param script The script engine to operate on. * @return The Unit Index of the closest unit within range and not friendly, * or 0 if none exists. */

 *   or 0 if none exists.
 */
uint16 Script_Structure_FindTargetUnit(ScriptEngine *script)
{
	PoolFindStruct find;
	Structure *s;
	Unit *u;
	uint32 distanceCurrent;
	uint32 targetRange;
	tile32 position;

	s = g_scriptCurrentStructure;
	targetRange = STACK_PEEK(1);
	distanceCurrent = 32000;
	u = NULL;

	find.houseID = HOUSE_INVALID;
	find.index   = 0xFFFF;
	find.type    = 0xFFFF;

	/* ENHANCEMENT -- The original code calculated distances from the top-left corner of the structure. */
	if (g_dune2_enhanced) {
		position = Tile_Center(s->o.position);
	} else {
		position = s->o.position;
	}

	while (true) {
		uint16 distance;
		Unit *uf;

		uf = Unit_Find(&find);
		if (uf == NULL) break;

		if (House_AreAllied(s->o.houseID, Unit_GetHouseID(uf))) continue;

		if (uf->o.type != UNIT_ORNITHOPTER) {
			if ((uf->o.seenByHouses & (1 << s->o.houseID)) == 0) continue;
		}

		distance = Tile_GetDistance(uf->o.position, position);
		if (distance >= distanceCurrent) continue;

		if (g_dune2_enhanced) {
			if (uf->o.type == UNIT_ORNITHOPTER) {
				if (distance > targetRange * 3) continue;
			} else {
				if (distance > targetRange) continue;
			}
		} else {
			if (uf->o.type == UNIT_ORNITHOPTER) {
				if (distance >= targetRange * 3) continue;
			} else {
				if (distance >= targetRange) continue;
			}
		}

		/* ENHANCEMENT -- The original code swapped the assignment, making it do nothing, Now it finds the closest unit to shoot at, what seems to be the intention */
		if (g_dune2_enhanced) distanceCurrent = distance;
		u = uf;