//------------------------------------------------------------------------------
// File: powerup.c
// Author: George Bain
// Date: May 22, 1997
// Description: Initialize the powerups and control the powerups AI
// Copyright (C) 1997 George Bain, All Rights Reserved
//------------------------------------------------------------------------------

//------------------------------------------------------------------------------
// I N C L U D E S
//------------------------------------------------------------------------------

#include <libps.h>	   // standard Sony library
#include "powerup.h"
#include "gfx.h"


//------------------------------------------------------------------------------
// Function: DrawPowerUp()
// Description: Register power up sprites into the OT
// Parameters: none
// Returns: void
// Notes: N/A
//------------------------------------------------------------------------------

void DrawPowerUp( void )
 {

    int count;

	for( count=0; count<NUM_POWERUPS; count++ ) 
	   {
		 
		  if( power_up[count].state == POWERUP_ALIVE )
			  GsSortFastSprite( &power_up[count].sprite, 
			                    &world_ordering_table[output_buffer_index], 0 );
		  
	   }// end for

 }// end DrawPowerUp




//------------------------------------------------------------------------------
// Function: ControlPowerUp()
// Description: Based on a random timer turn state of power up to Alive
//               and give a random direction either left or right, also
//               set the speed of power up
// Parameters: none
// Returns: void
// Notes: N/A
//------------------------------------------------------------------------------

void ControlPowerUp( void )
 {

    int index; 
    index = rand()%3;    // select a random power up

	if( power_up[index].state == POWERUP_DEAD
			&& ( rand()%400 == 1 ) )
	  {

	    // select a random direction

	    switch(rand()%2)  
		   {
		   case 0: // move powerup right
			 {
			   power_up[index].state = POWERUP_ALIVE;
			   power_up[index].motion_speed = POWERUP_SPEED;
			   power_up[index].sprite.x = 0;
			   power_up[index].sprite.y = RandLocation();
			  
			 }break;
		   case 1:  // move powerup left
			{
			  power_up[index].state = POWERUP_ALIVE;  
			  power_up[index].motion_speed = -(POWERUP_SPEED);
			  power_up[index].sprite.x = SCREEN_WIDTH;
			  power_up[index].sprite.y = RandLocation();
			 
			}break;

		   default:break;

	       }// end switch

	  }// end if DEAD

 }// end ControlPowerUp




//------------------------------------------------------------------------------
// Function: MovePowerUp()
// Description: If power up is ALIVE move the power up at the given speed 
//               and direction
// Parameters: none
// Returns: void
// Notes: N/A
//------------------------------------------------------------------------------

void MovePowerUp( void )
 {

	 int index;

	 for( index=0; index<NUM_POWERUPS; index++ ) 
	    {

		  if( power_up[index].state == POWERUP_ALIVE )
			{
				power_up[index].sprite.y += 0;
				power_up[index].sprite.x += power_up[index].motion_speed;

			    if( power_up[index].sprite.x > (SCREEN_WIDTH+15) || 
					power_up[index].sprite.x < -15 )
				    power_up[index].state = POWERUP_DEAD;
                
		    }// end

		}// end for

 }// end MovePowerUpLeft


//-----------------------------------EOF----------------------------------------