Here's a little code that spawns some enemies, once, when a combo on the screen becomes walkable. Of what use is such code?

You should ask Gemini Man.



Code:
// =======================================================
// BUBBLE_SPAWNER = Spawns enemies at a particular X,Y coordinate when 
// that coordinate becomes walkable.  Spawns only once.
// D0 - The X coordinate to spawn.
// D1 - The Y coordinate to spawn.
// D2 - The enemy type to spawn.
// D3 - The number of enemies to spawn.
// ======================================================

ffc script bubble_spawner{

	void run(int spawn_x, int spawn_y, int enemy_type, int num_enemies){

		while(!canMove(spawn_x, spawn_y)){
			Waitframe();
		} // end of while loop

		while(num_enemies >= 1){

			npc spawnee = Screen->CreateNPC(enemy_type);
			spawnee->X = spawn_x;
			spawnee->Y = spawn_y;

			num_enemies--;
	
		} // end of while loop
						
		
	} // end of void run

	// ===================================
	// Collision detection function
	// ===================================
	bool canMove(int x, int y){

		// x=23, y=130
		// Obviously in range...
		if(x<0 || x>255 || y<0 || y>175)
			return false;
		int mask=1111b;
		
		// x % 16 = 7, so
		// mask = 1111 & 0011 = 0011
		if(x%16<8)
			mask&=0011b;
		else
			mask&=1100b;
		
		// y % 16 = 2, so
		// mask = 0011 & 0101 = 0001
		if(y%16<8)
			mask&=0101b;
		else
			mask&=1010b;
	
		// All but the top-right quarter of the combo is solid, so ComboS = 1011
		// mask & ComboS = 0001 & 1011 = 0001
		// The result wasn't 0, so return false
		return ((Screen->ComboS[ComboAt(x, y)]&mask)==0);
	 }// end of canMove



} // end of FFC script