GBA game

#include <stdio.h>
#include <string.h>
#include <tonc.h>

#include "brin.h"
#include "pill.h"
#include "smallpill.h"
#include "collision_map.h"
#include "pill_collision.h"

///////////////////////////////foward declarations////////////////////////////////

void draw();
bool collision(int x, int y);
void init();
void input();
void obj_update();

///////////////////////////////////globals//////////////////////////////////////////

OBJ_ATTR obj_buffer[128];
OBJ_AFFINE *obj_aff_buffer= (OBJ_AFFINE*)obj_buffer;

OBJ_ATTR *pill= &obj_buffer[0];

int game_state = 1;

int pill_size = 2;

int pill_animation = 0;


int player_x;
int player_y;
int player_height = 16;
int player_width = 16;

int screen_width = 240;
int screen_height= 160;

int backgound1_x = 0;
int backgound1_y = 0;

unsigned short world_grid[64][32];

////////////////////////////////////////////draw///////////////////////////////////////////////

void draw()
{
	REG_BG1HOFS= backgound1_x;
	REG_BG1VOFS= backgound1_y;

	tte_write("#{P:0,0}");


	if (pill_size == 2)
	{
		tte_write("Big Pill");
	}
	else
	{
		tte_write("Small Pill");
	}
}

/////////////////////////////////////////////collision//////////////////////////////////////////

bool collision(int x, int y)
{
	int sprite_x,sprite_y;


	for(sprite_x =0; sprite_x<16; sprite_x++)
	{
		for(sprite_y =0; sprite_y<16; sprite_y++)
		{
			if((pill_collisionBitmap[sprite_x+sprite_y*16])&&
				(collision_mapBitmap[(sprite_x+x)+(sprite_y+y)*512]))
			{
				return true;
			}
		}
	}

	return false;
}


/////////////////////////////////////////////init//////////////////////////////////////////////

void init()
{
	backgound1_x = 0;
	backgound1_y = 0;

	//player_x = 14/pill_size;
	//player_y = 8/pill_size;

	player_x = 14*8;
	player_y = 8*8;


	memcpy(pal_bg_mem, brinPal, brinPalLen);
	// Load tiles into CBB 0
	memcpy(&tile_mem[0][0], brinTiles, brinTilesLen);
	// Load map into SBB 30
	memcpy(&se_mem[30][0], brinMap, brinMapLen);


	if(pill_size == 2)
	{
		memcpy(&tile_mem[4][0], pillTiles, pillTilesLen);
		memcpy(pal_obj_mem, pillPal, pillPalLen);
	}
	else
	{
		memcpy(&tile_mem[4][0], smallpillTiles, smallpillTilesLen);
		memcpy(pal_obj_mem, smallpillPal, smallpillPalLen);
	}

	oam_init(obj_buffer, 128);
	REG_DISPCNT= DCNT_MODE0 | DCNT_BG0 | DCNT_BG1 | DCNT_OBJ | DCNT_OBJ_1D;
	REG_BG1CNT= BG_CBB(0) | BG_SBB(30) | BG_4BPP | BG_REG_64x32;

	// Init BG 0 for text on screen entries.
	tte_init_se_default(0, BG_CBB(1)|BG_SBB(29));


	//initialise world grid
	int xx,yy, map;
	for(map = 0; map<2; map++)//the map is 64X32 effectively 2 32X32 maps to be addressed separately
	{
		for(yy=0;yy<32;yy++)
		{
			for(xx=0;xx<32;xx++)
			{
				world_grid[xx+32*map][yy] = brinMap[xx+yy*32+1024*map];
			}
		}
	}

	/*alternative version, does the same thing (faster, less readable)
	for(yy=0;yy<32;yy++)
	{
		for(xx=0;xx<64;xx++)
		{
			if(xx < 32)
			{
				world_grid[xx][yy] = brinMap[xx+yy*32];
			}
			else
			{
				world_grid[xx][yy] = brinMap[xx-32+yy*32+1024];
			}
		}
	}*/
}
////////////////////////////////////////////input//////////////////////////////////////////////

void input()
{
		key_poll();

		/*
		///////////////////////////////UP
		if ((key_is_down(KEY_UP))&&//the player is trying to go up
			(!world_grid[player_x*pill_size][(player_y-1)*pill_size])&&// check if the space is free
			(player_y>(4/pill_size)))//and is within the world limits
		{
			backgound1_y-=8*pill_size;
			player_y--;
		}

		//////////////////////////////DOWN
		if ((key_is_down(KEY_DOWN))&&//the player is trying to go down
			(!world_grid[player_x*pill_size][(player_y+1)*pill_size])&&// check if the space is free
			(player_y<((26/pill_size)-1)))//and is within the world limits
		{
			backgound1_y+=8*pill_size;
			player_y++;
		}

		//////////////////////////////RIGHT
		if ((key_is_down(KEY_RIGHT))&&//the player is trying to go right
			(!world_grid[(player_x+1)*pill_size][player_y*pill_size])&&// check if the space is free
			(player_x<((64/pill_size)-1)))//and is within the world limits
		{
			backgound1_x+=8*pill_size;
			player_x++;
			pill_animation = 0;
		}

		//////////////////////////////LEFT
		if ((key_is_down(KEY_LEFT))&&//the player is trying to go left
			(!world_grid[(player_x-1)*pill_size][player_y*pill_size])&&// check if the space is free
			(player_x>(6/pill_size)))//and is within the world limits
		{
			backgound1_x-=8*pill_size;
			player_x--;
			pill_animation = 1;
		}*/

				///////////////////////////////UP
		if ((key_is_down(KEY_UP))&&//the player is trying to go up
			(!collision(player_x,player_y-1)))
		{
			backgound1_y--;
			player_y--;
		}

		//////////////////////////////DOWN
		if ((key_is_down(KEY_DOWN))&&//the player is trying to go down
			(!collision(player_x,player_y+1)))
		{
			backgound1_y++;
			player_y++;
		}

		//////////////////////////////RIGHT
		if ((key_is_down(KEY_RIGHT))&&//the player is trying to go right
			(!collision(player_x+1,player_y)))
		{
			backgound1_x++;
			player_x++;
		}

		//////////////////////////////LEFT
		if ((key_is_down(KEY_LEFT))&&//the player is trying to go left
			(!collision(player_x-1,player_y)))
		{
			backgound1_x--;
			player_x--;
		}

		if(key_hit(KEY_SELECT))
		{
			/*
			game_state=0;
			tte_write("#{P:0,0}");
			tte_write("#{es}");

			OAM_CLEAR();//clear the sprites
			memset(&tile_mem[4][0], 0, pillTilesLen);
			memset(pal_obj_mem, 0, pillPalLen);

			REG_DISPCNT= DCNT_MODE0 | DCNT_BG0;//disable background 1
			*/
		}

}

////////////////////////////////////////////obj_update/////////////////////////////////////////

void obj_update()
{
	//int x= 96, y= 32;
	int x = (screen_width - player_width)/2;
	int y = (screen_height)/2 - player_height;

	u32 tid= 0, pb= 0;		// tile id, pal-bank

	if(pill_size == 2)
	{

		obj_set_attr(pill,
			ATTR0_SQUARE,				// Square, regular sprite
			ATTR1_SIZE_16,					// 16x16p,
			ATTR2_PALBANK(pb) | tid);		// palbank 0, tile 0
	}
	else
	{
		obj_set_attr(pill,
			ATTR0_SQUARE,				// Square, regular sprite
			ATTR1_SIZE_8,					// 8x8p,
			ATTR2_PALBANK(pb) | tid);		// palbank 0, tile 0
	}

	if (pill_animation == 1)
	{
		pill->attr1 ^= ATTR1_HFLIP;
	}


	// Hey look, it's one of them build macros!
	pill->attr2= ATTR2_BUILD(tid, pb, 0);
	obj_set_pos(pill, x, y);

	oam_copy(oam_mem, obj_buffer, 1);	// only need to update one

}

////////////////////////////////////////main/////////////////////////////////////

int main()
{

	// enable isr switchboard and VBlank interrupt
	irq_init(NULL);
	irq_add(II_VBLANK, NULL);

	int selection = 2;

	REG_DISPCNT= DCNT_MODE0 | DCNT_BG0;

	// Init BG 0 for text on screen entries.
	tte_init_se_default(0, BG_CBB(1)|BG_SBB(29));

	/////////////////////////skip the start screen///////////////////

	game_state = 1;//start the game
	pill_size = selection;
	init();
	tte_write("#{es}");//clear the screen

	/////////////////////////////////////////////////////////////////

	while(1)
	{

		switch (game_state)
		{
			case 0:///////////////////////////state 0(start screen)//////////////////////////////

				/////////////////////////skip the start screen///////////////////

				game_state = 1;//start the game
				pill_size = selection;
				init();
				tte_write("#{es}");//clear the screen

				break;
				/////////////////////////////////////////////////////////////////

				while(1)
				{

					//vid_vsync();
					VBlankIntrWait();
					key_poll();



					if (selection == 2)
					{
						tte_write("#{P:68,64}");
						tte_write(" ->Big Pill<-    ");

						tte_write("#{P:68,72}");
						tte_write("  Small Pill      ");
					}
					else
					{
						tte_write("#{P:68,64}");
						tte_write("   Big Pill        ");

						tte_write("#{P:68,72}");
						tte_write("->Small Pill<-     ");
					}

					if(key_hit(KEY_UP))
					{
						selection = 2;
					}

					if(key_hit(KEY_DOWN))
					{
						selection = 1;
					}

					if(key_hit(KEY_START))
					{
						game_state = 1;//start the game
						pill_size = selection;
						init();
						tte_write("#{es}");//clear the screen

						break;//leave infinite loop
					}


				}
			break;
			case 1://////////////////////////////state 1 game play//////////////////////////


				//game loop
				while(1)
				{
					//vid_vsync(); better to use the interrupt version
					VBlankIntrWait();

					input();

					if(game_state == 0)
					{
						break;
					}

					obj_update();

					draw();

				}


			break;
		}
	}

	return 0;
}