// Header file for GFORCE.C

#include "pad.h"

#define NUMCOLOURS 32
#define GRAVITY_FORCE -0.03
#define AIR_RESISTANCE 0.02
#define ENGINE_POWER 0.2
#define NUM_LIVES 7
#define MAX_BULLETS 50
#define BULLET_POWER 4.0
#define BULLET_LIFE 100

enum { FALSE, TRUE };

typedef struct {
  short x, y;
} POINT;

typedef struct {
  float x, y;           // position
  float xold, yold;
  float vx, vy;         // velocity constant after firing
  u_long out;           // Bullet out flag (used as timer)
} BULLET;


typedef struct {
  short x, y;           // Player virtual screen coordinates
  short xold, yold;

  char angle;           // Angle (0-35) 10 degree steps
                        // uses lookup tables for sin&cos angle
  float px, py;         // Player position as floating point
  float vx, vy;         // Velocity vectors (fp)

  u_char thrust;        // Thrust flag
  u_char lives;         // Lives left
  u_char alive;         // Death flag
  u_char onbase;        // On base flag
  u_char exploding;     // Exploding (value = time left exploding)
  u_char playing;       // Is player playing
  u_char newplayer;     // Newplayer flag

} PLAYER;


// Function prototypes
void InitPlayers(int);                  // takes value 1 or 2
int UpdatePlayers();                    // Returns 0,1 or 2: player dead
void ResetPlayer(u_char);               // puts player back to base

void FireBullet(u_char);                // fire bullet (player)
void ClearBullets();
void DrawBullets();
void MapLoad(u_char);
u_char ReadByte();
void PutPixel(short, short, u_char);    // Putpixel
u_char GetPixel(short, short);          // used as test for collision detection
void InitFrameBuffer();
void SavePlayerBKImage(u_char);         // Save area for each player
void PutPlayerBKImage(u_char);          // Restore a saved image
u_char DrawPlayer(u_char);              // Draws players on virtual screen

void VidModeChange();

// Global variables
u_long PadStatus;

PLAYER player1;
PLAYER player2;
RECT P1scr, P2scr;                      // Player screen areas
RECT *scr, vir;                         // Visible and virtual screens
RECT pix, tmp;                          // Used with PutBKImage/SaveBKImage/bullets
RECT Clut;                              // Used in PutPixel
POINT StartP1;                          // Player starting coords (set in MapLoad)
POINT StartP2;

short maxyoffset;                       // Used for split screen
int Init_Once = FALSE;                  // Initialised once flag

u_long *MAPADDR;                        // Pointer to map/dat data
u_long offset;
u_char bytenum;


// Players' list of BULLETS
BULLET P1Bullet[MAX_BULLETS];
BULLET P2Bullet[MAX_BULLETS];


// Palette RGB values for map - first 32 defined here, can use all 256 though
u_char PALETTE[96] =
{
  0,   0,   0, 240, 240, 240, 224,  96,  32,  32,  80, 144, 240, 240,  32,
 64, 112, 176, 112, 160, 208, 160, 208, 240, 176,  16,   0, 128,   0,   0,
192, 192, 192, 144, 144, 144,  48,  48,  48, 224, 176, 112, 192, 128,  64,
160,  96,  32, 128,  64,   0, 160, 160, 160, 112, 112, 112, 160, 160, 160,
 32, 192,   0,   0, 128,   0,   0, 160,   0,   0, 160,   0, 160, 160, 160,
 48, 192, 192,  48, 112, 112,  48, 192, 192,   0, 160, 160,   0,  80,  80,
  0, 112, 112,   0, 112, 112
};


// Sin & Cos lookup table
float SIN[36] =
{
     0, 0.173, 0.342, 0.5, 0.643, 0.766, 0.866, 0.940, 0.985,
  1, 0.985, 0.940, 0.866, 0.766, 0.643, 0.5, 0.342, 0.173,
     0, -0.173, -0.342, -0.5, -0.643, -0.766, -0.866, -0.940, -0.985,
 -1, -0.985, -0.940, -0.866, -0.766, -0.643, -0.5, -0.342, -0.173
};
float COS[36] =
{
  1, 0.985, 0.940, 0.866, 0.766, 0.643, 0.5, 0.342, 0.173,
     0, -0.173, -0.342, -0.5, -0.643, -0.766, -0.866, -0.940, -0.985,
 -1, -0.985, -0.940, -0.866, -0.766, -0.643, -0.5, -0.342, -0.173,
     0, 0.173, 0.342, 0.5, 0.643, 0.766, 0.866, 0.940, 0.985
};