aliens.cpp

After decades of war one company, who had gained powerful supplying both sides with weaponary, steps

/*
Copyright (C) 2003 Parallel Realities

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

*/

#include "aliens.h"

signed char placeAlien(object *theEnemy)
{
	if (rand() % 2 == 0)
		theEnemy->x = Math::rrand(800, 1600);
	else
		theEnemy->x = Math::rrand(-800, 0);

	if (rand() % 2 == 0)
		theEnemy->y = Math::rrand(600, 1200);
	else
		theEnemy->y = Math::rrand(-600, 0);

	if (currentGame.area == 24)
	{
		theEnemy->x = 800;
		theEnemy->y = Math::rrand(200, 400);
	}

	for (int i = 0 ; i < MAX_ALIENS ; i++)
	{
		if ((enemy[i].owner != theEnemy) && (enemy[i].shield > 0))
		{
			if (Collision::collision(theEnemy->x, theEnemy->y, theEnemy->image[0]->w, theEnemy->image[0]->h, enemy[i].x, enemy[i].y, enemy[i].image[0]->w, enemy[i].image[0]->h))
				return 0;
		}
	}

	return 1;
}

/*
This simply pulls back an alien from the array that is
"dead" (no shield) and returns the index number so we can have
a new one.
*/
int getAlien()
{
	for (int i = 0 ; i < engine.maxAliens ; i++)
	{
		if (!enemy[i].active)
		{
			return i;
		}
	}

	return -1;
}

void addDrone(object *host)
{
	int index = getAlien();

	if (index == -1)
		return;

	enemy[index] = defEnemy[CD_DRONE];
	enemy[index].active = 1;
	enemy[index].face = rand() % 2;
	enemy[index].owner = &enemy[index]; // Most enemies will own themselves
	enemy[index].target = &enemy[index];
	enemy[index].thinktime = (50 + rand() % 50);
	enemy[index].systemPower = enemy[index].maxShield;
	enemy[index].deathCounter = 0 - (enemy[index].maxShield * 3);
	enemy[index].hit = 0;

	enemy[index].x = host->x + rand() % 50;
	enemy[index].y = host->y + rand() % 50;
}

void addSmallAsteroid(object *host)
{
	if (engine.missionCompleteTimer != 0)
		return;

	int index = -1;
	int debris = 1 + rand() % 10;

	for (int i = 0 ; i < debris ; i++)
		addBullet(&weapon[W_ROCKETS], host, 0, 0);

	for (int i = 10 ; i < 20 ; i++)
		if (enemy[i].active == 0)
			index = i;

	if (index == -1)
		return;

	if ((rand() % 10) > 3)
	{
		enemy[index] = defEnemy[CD_ASTEROID2];
		enemy[index].imageIndex[0] = enemy[index].imageIndex[1] = 39 + rand() % 2;
		enemy[index].image[0] = graphics.shipShape[enemy[index].imageIndex[0]];
		enemy[index].image[1] = graphics.shipShape[enemy[index].imageIndex[1]];
	}
	else
	{
		enemy[index] = defEnemy[CD_DRONE];
	}

	enemy[index].owner = &enemy[index]; // Most enemies will own themselves
	enemy[index].target = &enemy[index];
	enemy[index].thinktime = 1;
	enemy[index].systemPower = enemy[index].maxShield;
	enemy[index].deathCounter = 0 - (enemy[index].maxShield * 3);
	enemy[index].hit = 0;

	enemy[index].x = host->x;
	enemy[index].y = host->y;
	enemy[index].active = 1;
}

signed char addAlien()
{
	int index = getAlien();

	if ((index == -1) || (currentGame.area == 23) || (currentGame.area == 26))
		return 0;

	signed char *alienArray;
	signed char numberOfAliens = 1;

	alienArray = new signed char[5];

	switch(currentGame.area)
	{
		case 0:
		case 3:
		case 11:
			numberOfAliens = 1;
			alienArray[0] = CD_DUALFIGHTER;
			break;
		case 1:
		case 2:
		case 4:
		case 5:
			numberOfAliens = 2;
			alienArray[0] = CD_DUALFIGHTER;
			alienArray[1] = CD_PROTOFIGHTER;
			break;
		case 9:
		case 13:
		case 14:
		case 16:
			numberOfAliens = 4;
			alienArray[0] = CD_DUALFIGHTER;
			alienArray[1] = CD_PROTOFIGHTER;
			alienArray[2] = CD_MISSILEBOAT;
			alienArray[3] = CD_AIMFIGHTER;
			break;
		case 25:
			numberOfAliens = 6;
			alienArray[0] = CD_DUALFIGHTER;
			alienArray[1] = CD_PROTOFIGHTER;
			alienArray[2] = CD_MISSILEBOAT;
			alienArray[3] = CD_AIMFIGHTER;
			alienArray[4] = CD_ESCORT;
			alienArray[5] = CD_MOBILE_RAY;
			break;
		case 22:
			numberOfAliens = 2;
			alienArray[0] = CD_AIMFIGHTER;
			alienArray[1] = CD_DUALFIGHTER;
			break;
		case 7:
		case 8:
			numberOfAliens = 3;
			alienArray[0] = CD_DUALFIGHTER;
			alienArray[1] = CD_PROTOFIGHTER;
			alienArray[2] = CD_AIMFIGHTER;
			break;
		case 18:
			numberOfAliens = 2;
			alienArray[0] = CD_DUALFIGHTER;
			alienArray[1] = CD_MINER;
			break;
		case 10:
		case 15:
			numberOfAliens = 1;
			alienArray[0] = CD_ASTEROID;
			break;
		case 24:
			numberOfAliens = 2;
			alienArray[0] = CD_ASTEROID;
			alienArray[1] = CD_ASTEROID2;
			break;
		case MAX_MISSIONS - 1:
			numberOfAliens = 3;
			alienArray[0] = CD_DUALFIGHTER;
			alienArray[1] = CD_MISSILEBOAT;
			alienArray[2] = CD_AIMFIGHTER;
			if (currentGame.system == 2)
			{
				numberOfAliens = 4;
				alienArray[3] = CD_PROTOFIGHTER;
			}
			break;
		default:
			numberOfAliens = 1;
			alienArray[0] = CD_DUALFIGHTER;
			break;
	}

	signed char randEnemy = alienArray[rand() % numberOfAliens];

	if ((currentGame.area != 10) && (currentGame.area != 15) && (currentGame.area != 24))
	{
		if ((currentGame.system == 1) && (currentGame.area == MAX_MISSIONS - 1))
		{
			if ((rand() % 5) == 0)
				randEnemy = CD_SLAVETRANSPORT;
		}

		if ((rand() % 6) == 0)
			randEnemy = CD_TRANSPORTSHIP;
	}

	delete(alienArray);

	enemy[index] = defEnemy[randEnemy];
	enemy[index].active = 1;
	enemy[index].face = rand() % 2;
	enemy[index].owner = &enemy[index]; // Most enemies will own themselves
	enemy[index].target = &enemy[index];
	enemy[index].thinktime = (50 + rand() % 50);
	enemy[index].systemPower = enemy[index].maxShield;
	enemy[index].deathCounter = 0 - (enemy[index].maxShield * 3);
	enemy[index].hit = 0;

	Math::limitInt(&enemy[index].deathCounter, -250, 0);

	// Attempts to place an alien. If it fails, the alien is deactivated.
	for (int i = 0 ; i < 100 ; i++)
	{
		if (placeAlien(&enemy[index]))
			break;
		enemy[index].active = 0;

		return 0;
	}

	if (enemy[index].classDef == CD_CARGOSHIP)
		addCargo(&enemy[index], P_CARGO);

	if (enemy[index].classDef == CD_MOBILE_RAY)
		enemy[index].shield = 25;

	if (enemy[index].classDef == CD_ESCORT)
		enemy[index].shield = 50;

	enemy[index].dx = Math::rrand(-2, 2);
	enemy[index].dy = Math::rrand(-2, 2);

	enemy[index].ammo[0] = 0;

	if (currentGame.area == 18)
		enemy[index].flags += FL_HASMINIMUMSPEED;

	return 1;
}

void getPreDefinedAliens()
{
	FILE *fp;
	char string[255];
	strcpy(string, "");

	int index, alienType, placeAttempt;
	int barrierSpeed = 1;

	sprintf(string, "data/aliens%d.dat", currentGame.area);
	#if USEPACK
	int dataLocation = locateDataInPak(string, 0);
	if (dataLocation == -1)
		return;
	fp = fopen(PACKLOCATION, "rb");
	fseek(fp, dataLocation, SEEK_SET);
	#else
	fp = fopen(string, "rb");
	if (fp == NULL)
		return;
	#endif

	fscanf(fp, "%d ", &index);

	while (index != -1)
	{
		placeAttempt = 0;

		fscanf(fp, "%d ", &alienType);

		enemy[index] = defEnemy[alienType];
		enemy[index].owner = &enemy[index];
		enemy[index].target = &enemy[index];
		enemy[index].face = rand() % 2;
		enemy[index].active = 1;

		/*
		we make 1000 attempts to place this enemy since it is required. If after 1000 attempts
		we still have managed to place the alien, then it simple isn't going to happen and we
		will just exit the same. The chances of this happening are very very low!
		*/
		while (true)
		{
			placeAttempt++;

			if (placeAlien(&enemy[index]))
				break;

			if (placeAttempt > 1000)
				showErrorAndExit(2, "");
		}

		if (currentGame.area == 2)
			addCargo(&enemy[index], P_CARGO);
		else if (currentGame.area == 7)
			addCargo(&enemy[index], P_PHOEBE);

		if (index == WC_KLINE)
		{
			enemy[WC_KLINE].target = &player;
			if (currentGame.area == 25)
				enemy[WC_KLINE].shield = 500;
		}

		if (enemy[index].classDef == CD_CLOAKFIGHTER)
		{
			enemy[index].active = 0;
			enemy[index].maxShield = enemy[index].shield = 400;
			enemy[index].flags -= FL_RUNSAWAY;
			enemy[index].speed = 3;
		}

		if ((enemy[index].classDef == CD_MOBILE_RAY) && (index >= 11))
		{
			enemy[index].active = 0;
		}

		if (enemy[index].classDef == CD_FIREFLY)
		{
			enemy[index].active = 0;
		}

		if (enemy[index].classDef == CD_BARRIER)
		{
			enemy[index].owner = &enemy[WC_BOSS];
			enemy[index].speed = barrierSpeed;
			barrierSpeed++;
		}

		if ((currentGame.area == 17) && (enemy[index].classDef == CD_BOSS))
		{
			enemy[index].imageIndex[1] = 29;
			enemy[index].flags += FL_IMMORTAL;
		}

		if (currentGame.area == 18)
			enemy[index].flags += FL_HASMINIMUMSPEED;

		if (currentGame.area == 23)
		{
			enemy[index].flags = FL_WEAPCO;
			if (index == WC_BOSS)
				enemy[index].chance[1] = 5;
		}

		fscanf(fp, "%d ", &index);
	}

	fclose(fp);

	if (currentGame.area == 5)
	{
		enemy[WC_BOSS].target = &player;
		enemy[WC_BOSS].x = -400;
		enemy[WC_BOSS].y = 300;

		enemy[13].owner = &enemy[WC_BOSS];
		enemy[13].target = &player;
		enemy[13].dx = -25;
		enemy[13].dy = -21;

		enemy[12].owner = &enemy[WC_BOSS];
		enemy[12].target = &player;
		enemy[12].dx = -20;
		enemy[12].dy = 37;
	}
	else if ((currentGame.area == 11) || (currentGame.area == 14))
	{
		enemy[WC_BOSS].target = &player;
		enemy[WC_BOSS].x = -400;
		enemy[WC_BOSS].y = 300;

		enemy[13].owner = &enemy[WC_BOSS];
		enemy[13].target = &player;
		enemy[13].dx = 15;
		enemy[13].dy = -22;

		enemy[12].owner = &enemy[WC_BOSS];
		enemy[12].target = &player;
		enemy[12].dx = 15;
		enemy[12].dy = 22;

		enemy[11].owner = &enemy[13];
		enemy[11].target = &player;
		enemy[11].dx = -35;
		enemy[11].dy = -12;

		enemy[10].owner = &enemy[12];
		enemy[10].target = &player;
		enemy[10].dx = -35;
		enemy[10].dy = 20;

		if (currentGame.area == 14)
		{
			enemy[WC_BOSS].AIType = AI_EVASIVE;

			for (int i = 10 ; i < 15 ; i++)
			{
				enemy[i].imageIndex[0] += 15;
				enemy[i].imageIndex[1] += 15;

				enemy[i].image[0] = graphics.shipShape[enemy[i].imageIndex[0]];
				enemy[i].image[1] = graphics.shipShape[enemy[i].imageIndex[1]];
			}
		}
	}
	else if (currentGame.area == 21)
	{
		enemy[WC_BOSS].target = &player;
		enemy[WC_BOSS].x = 400;
		enemy[WC_BOSS].y = 300;

		enemy[13].owner = &enemy[WC_BOSS];
		enemy[13].dy = 20;

		enemy[12].owner = &enemy[WC_BOSS];
		enemy[12].dy = -16;
	}
}

void addFriendly(int type)
{
	if (type != FR_SID)
		enemy[type] = defEnemy[CD_FRIEND];
	else
		enemy[type] = defEnemy[CD_SID];

	enemy[type].owner = &enemy[type];
	enemy[type].target = &enemy[type];
	enemy[type].active = 1;

	if (rand() % 2 == 0)
		enemy[type].x = Math::rrand(400, 550);
	else
		enemy[type].x = Math::rrand(250, 400);

	if (rand() % 2 == 0)
		enemy[type].y = Math::rrand(300, 450);
	else
		enemy[type].y = Math::rrand(150, 300);

	if (type == FR_PHOEBE)
		enemy[type].classDef = CD_PHOEBE;

	if (type == FR_URSULA)
		enemy[type].classDef = CD_URSULA;

	// For the sake of it being the final battle :)
	if (currentGame.area == 25)
		enemy[type].flags += FL_IMMORTAL;
}

void setTarget(int index)
{
	engine.targetIndex = index;
	engine.targetShield = 85;
	engine.targetShield /= enemy[index].shield;

	engine.targetArrowTimer = -1;
	if (currentGame.area == 10)
		engine.targetArrowTimer = 0;
}

void initAliens()
{
	for (int i = 0 ; i < MAX_ALIENS ; i++)
	{
		enemy[i].active = 0;