Function UpdateBubbles

TombEngine/Game/effects/bubble.cpp:137–206

	}

	void UpdateBubbles()
	{
		constexpr auto LIFE_FULL_SCALE		= std::max(BUBBLE_LIFE_MAX - 0.25f, 0.0f);
		constexpr auto LIFE_START_FADING	= std::min(1.0f, BUBBLE_LIFE_MAX);
		constexpr int  ROOM_UPDATE_INTERVAL = 10;

		if (Bubbles.empty())
			return;

		for (auto& bubble : Bubbles)
		{
			if (bubble.Life <= 0.0f)
				continue;

			bubble.StoreInterpolationData();

			int prevRoomNumber = bubble.RoomNumber;

			int updateOffset = (int)(bubble.Position.x + bubble.Position.y + bubble.Position.z) % ROOM_UPDATE_INTERVAL;
			if (GlobalCounter % ROOM_UPDATE_INTERVAL == updateOffset)
			{
				auto roomVector = RoomVector(bubble.RoomNumber, int(bubble.Position.y - bubble.Gravity));
				auto testPosition = Vector3i(bubble.Position.x, bubble.Position.y - bubble.Gravity, bubble.Position.z);
				bubble.RoomNumber = GetRoomVector(roomVector, testPosition).RoomNumber;;
			}

			// Out of water.
			if (bubble.RoomNumber != prevRoomNumber && !TestEnvironment(ENV_FLAG_WATER, bubble.RoomNumber))
			{
				// Hit water surface; spawn ripple.
				SpawnRipple(
					Vector3(bubble.Position.x, g_Level.Rooms[prevRoomNumber].TopHeight, bubble.Position.z),
					bubble.RoomNumber,
					((bubble.SizeMax.x + bubble.SizeMax.y) / 2) * 0.5f,
					(int)RippleFlags::SlowFade);

				bubble.Life = 0.0f;
				continue;
			}
			// Hit ceiling. NOTE: This is a hacky check. New collision fetching should provide fast info on a need-to-know basis.
			else if (bubble.RoomNumber == prevRoomNumber && bubble.Position.y <= g_Level.Rooms[prevRoomNumber].TopHeight)
			{
				bubble.Life = 0.0f;
				continue;
			}

			// Oscillate size according to period.
			bubble.OscillationPeriod += bubble.OscillationVelocity;
			bubble.Size = Vector2(
				(bubble.SizeMin.x / 2) + ((bubble.SizeMax.x - bubble.SizeMin.x) * (0.5f + (0.5f * sin(bubble.OscillationPeriod)))),
				(bubble.SizeMin.y / 2) + ((bubble.SizeMax.y - bubble.SizeMin.y) * (0.5f + (0.5f * cos(bubble.OscillationPeriod + 1.0f)))));
			bubble.Size *= Lerp(0.0f, 1.0f, bubble.Life / std::round(LIFE_FULL_SCALE * FPS));

			// Update opacity.
			float alpha = 1.0f - (bubble.Life / std::round(LIFE_START_FADING * FPS));
			float opacity = Lerp(bubble.OpacityStart, 0.0f, alpha);
			bubble.Color.w = opacity;