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main.c
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main.c
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/*
* Title: Space Critters for Agon Light
* Author: James Higgs (Jum Hig)
* Created: 2023
* Last Updated: 2023-12-21
*
* Revisions:
* 2023-04-21 - Updated to use MOS 1.03
* 2023-12-21 - Updated to use MOS 1.04
*/
// VDP functions needed:
// - Query sprite collisions (from fabGL)
// TODO
// - [DONE] Custom font
// - [DONE] Paletted bitmap upload (convert 4-bit image data to 24-bit when uploading)
// - [DONE] Player explode particle effects
// - Small bird to big bird transition
// - Big bird split transition
// - Boss battle
// - Better sound (using updated 1.04 engine) - Envelopes, different waveforms
// Ideas:
// 1. Big bird splits into 2 when shot
// 2. Dead birds drop from the sky (with flames on wings), can kill you
// 3. If you clip a bird's wing, it drops down with erratic side movement
// 4. Birds have random "divebomb" behaviour
//
// Levels (affects SetupSprites() and UpdateEnemies()):
// 1. Eggs to smal birds
// 2. Eggs to small birds to big birds
// 3. Eggs to big birds, split into 2 if shot
// 4. Boss?
// Levels repeat like this (1-4 above), but:
// - number of enemies increases
// - Enemy bullet frequency increases
// - Enemy bullet speed increases
// - Enemies start shooting bullets at an angle
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <gpio.h> // For joystick
#include "mos-interface.h"
#include "vdp.h"
#include "vdp_audio.h"
#include "fantasia_font.h" // Custom font
#include "sprites/ufos.h" // for bullets
#include "sprites/playerShip16.h" // Paletted player ship data (1/8th size)
#include "sprites/explosions16.h" // 4-bit paletted version
#include "sprites/explosions100.h" // sideways explosion for big birds (now 4-bit palletised)
#include "sprites/eggs16.h" // 4-bit paletted
#include "sprites/bird_16x12.h" // now 4-bit paletted
#include "sprites/bird_32x24_shaded.h" // now 4-bit paletted
#include "sprites/fragments.h" // 8x8, 4-bit palette
#include "sprites/title16_16x16.h" // 4-bit paletted version
#define SCREEN_WIDTH 320
#define SCREEN_HEIGHT 240
#define MAX_SPRITES 32
#define FIRSTENEMYBULLETID 2 // index of the first enemy bullet in the object/sprite array
#define LASTENEMYBULLETID 11
#define FIRSTENEMYID 12 // index of the first enemy in the object array
#define MAX_ENEMIES 12
#define LASTENEMYID (FIRSTENEMYID + MAX_ENEMIES - 1) // index of the last enemy in the object array
#define EGG_STARTFRAME 0
#define SBIRD_STARTFRAME 8
#define BBIRD_STARTFRAME 15
#define EXPLOSION_STARTFRAME 23
#define EXPLOSION100_STARTFRAME 32
#define MAX_BOMBDROPCHANCE 100 // Chance of any enemy dropping a bullet every frame (n/65536)
#define FREE_LIFE_INTERVAL 5000
// Bitmaps ids
enum {
BID_PLAYER0 = 0, // 0 to 7 - Player and player bullet bitmap id's
BID_PLAYER1,
BID_PLAYER2,
BID_PLAYER3,
BID_UNUSED1,
BID_UNUSED2,
BID_UNUSED2,
BID_PLAYERBULLET,
BID_EXPLOSION0, // 8 to 15 - Explosions id's
BID_EXPLOSION1,
BID_EXPLOSION2,
BID_EXPLOSION3,
BID_EXPLOSION4,
BID_EXPLOSION5,
BID_EXPLOSION6,
BID_EXPLOSION7,
BID_EGGS0, // 16 to 23 - Eggs id's
BID_EGGS1,
BID_EGGS2,
BID_EGGS3,
BID_EGGS4,
BID_EGGS5,
BID_EGGS6,
BID_EGGS7,
BID_SBIRD0, // 24 to 31 - Small bird id's
BID_SBIRD1,
BID_SBIRD2,
BID_SBIRD3,
BID_SBIRD4,
BID_SBIRD5,
BID_SBIRD6,
BID_ENEMYBULLET,
BID_BBIRD0, // 32 to 38 - Big bird id's
BID_BBIRD1,
BID_BBIRD2,
BID_BBIRD3,
BID_BBIRD4,
BID_BBIRD5,
BID_BBIRD6,
BID_TITLE0, // 39 to 47 - Title character sprites
BID_TITLE1,
BID_TITLE2,
BID_TITLE3,
BID_TITLE4,
BID_TITLE5,
BID_TITLE6,
BID_TITLE7,
BID_TITLE8,
BID_EXPLOSION100_0, // 48 to 56 - Explosion100 id's
BID_EXPLOSION100_1,
BID_EXPLOSION100_2,
BID_EXPLOSION100_3,
BID_EXPLOSION100_4,
BID_EXPLOSION100_5,
BID_EXPLOSION100_6,
BID_EXPLOSION100_7,
BID_EXPLOSION100_8,
BID_FRAGMENT0,
BID_FRAGMENT1,
BID_FRAGMENT2,
BID_FRAGMENT3
};
// Object types (type index)
enum {
PLAYER = 0,
PLAYERBULLET,
ENEMYBULLET,
EGG,
BIRD,
BIGBIRD,
FRAGMENT // For "particle effects"
};
// Object states
enum {
ST_INACTIVE = 0,
ST_ACTIVE,
ST_EGG,
ST_HATCHING,
ST_MOVELEFT,
ST_MOVERIGHT,
ST_MOVERANDOM,
ST_SPLITTING,
ST_FRAGMENT,
ST_DYING
};
// Direction bitmask
enum {
DIRN_NONE = 0,
DIRN_LEFT = 1,
DIRN_RIGHT = 2,
DIRN_UP = 4,
DIRN_DOWN = 8
};
// Game object
typedef struct
{
UINT8 type;
UINT16 x;
UINT16 y;
UINT8 frame; // Current frame of animation
UINT8 state; // Current state of this object
UINT8 dirn; // Current direction of the object
UINT16 counter; // Internal counter for object logic
} OBJECT;
OBJECT objects[MAX_SPRITES] = {
{ PLAYER, 120, 50, 0, 0, 0, 0 },
{ PLAYERBULLET, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0 }
};
// Points for each enemy type (for scoring)
const UINT16 PointsPerType[8] = {
0, // PLAYER = 0,
0, // PLAYERBULLET,
0, // ENEMYBULLET,
50, // EGG,
50, // BIRD,
100, // BIGBIRD
0
};
// Audio channel allocation:
// 0 - Player fire
// 1.- Enemy fire
// 2 - Player explosion
// 3 - Enemy explosion
// 4.- Extra life
enum {
SFX_PLAYERFIRE = 0,
SFX_ENEMYFIRE,
SFX_PLAYEREXPLODE,
SFX_ENEMYEXPLODE,
SFX_ENEMYSPLIT,
SFX_EXTRALIFE,
SFX_COUNT
};
// Global Variables (oooh!)
UINT8* g_keyDownMap = NULL; // Pointer to MOS keyboard key down map
int bombDropChance = 40; // 40 / 65536 chance
UINT8 lives = 3;
UINT16 score = 0;
int hiscore = 0;
// Check if a key is pressed in the keydown map (new MOS 1.04 functionality)
// @param[in] mapIndex Index of the *byte* to check in the 128-bit key map
// @param[in] mask Bit mask for the key we want in the index byte
BOOL IsKeyPressed(UINT8 mapIndex, UINT8 mask)
{
if (mapIndex > 15)
return FALSE;
if (NULL == g_keyDownMap)
{
// Get global pointer to MOS keydown map
g_keyDownMap = mos_kbmap();
}
if ((g_keyDownMap[mapIndex] & mask) == mask)
return TRUE;
else
return FALSE;
}
// Get random number between 0 and 255
UINT8 rand255()
{
return (rand() & 0xFF);
}
// Upload custom font to the VDP
void UploadCustomFont()
{
// Custom "Fantasia" font starts at char 32
UINT8 i;
for (i = 0; i < 64; i++)
vdp_redefineChar(i + 32, fantasia_font + (i * 8));
}
// Upload bitmap and sprite data to the VDP
void UploadBitmaps()
{
// Player and player bullet uses bitmaps 0 to 7
//vdp_bitmapSendData(BID_PLAYER0, PLAYER_WIDTH, PLAYER_HEIGHT, playerData[0]);
//vdp_bitmapSendData(BID_PLAYER1, PLAYER_WIDTH, PLAYER_HEIGHT, playerData[1]); // player exploding 1
//vdp_bitmapSendData(BID_PLAYER2, PLAYER_WIDTH, PLAYER_HEIGHT, playerData[2]); // player exploding 2
//vdp_bitmapSendData(BID_PLAYER3, PLAYER_WIDTH, PLAYER_HEIGHT, playerData[3]); // player exploding 3
vdp_bitmapSendData16(BID_PLAYER0, PLAYER_WIDTH, PLAYER_HEIGHT, playerData[0], playerDataPalette);
vdp_bitmapSendData16(BID_PLAYER1, PLAYER_WIDTH, PLAYER_HEIGHT, playerData[1], playerDataPalette); // player exploding 1
vdp_bitmapSendData16(BID_PLAYER2, PLAYER_WIDTH, PLAYER_HEIGHT, playerData[2], playerDataPalette); // player exploding 2
vdp_bitmapSendData16(BID_PLAYER3, PLAYER_WIDTH, PLAYER_HEIGHT, playerData[3], playerDataPalette); // player exploding 3
vdp_bitmapSendData(BID_PLAYERBULLET, 16, 16, playerBulletData); // player bullet
// Explosions use bitmaps 8 to 15
//vdp_bitmapSendData(BID_EXPLOSION0, EXPLOSION_WIDTH, EXPLOSION_HEIGHT, explosionData[0]);
//vdp_bitmapSendData(BID_EXPLOSION1, EXPLOSION_WIDTH, EXPLOSION_HEIGHT, explosionData[1]);
//vdp_bitmapSendData(BID_EXPLOSION2, EXPLOSION_WIDTH, EXPLOSION_HEIGHT, explosionData[2]);
//vdp_bitmapSendData(BID_EXPLOSION3, EXPLOSION_WIDTH, EXPLOSION_HEIGHT, explosionData[3]);
//vdp_bitmapSendData(BID_EXPLOSION4, EXPLOSION_WIDTH, EXPLOSION_HEIGHT, explosionData[4]);
//vdp_bitmapSendData(BID_EXPLOSION5, EXPLOSION_WIDTH, EXPLOSION_HEIGHT, explosionData[5]);
//vdp_bitmapSendData(BID_EXPLOSION6, EXPLOSION_WIDTH, EXPLOSION_HEIGHT, explosionData[6]);
//vdp_bitmapSendData(BID_EXPLOSION7, EXPLOSION_WIDTH, EXPLOSION_HEIGHT, explosionData[7]);
vdp_bitmapSendData16(BID_EXPLOSION0, EXPLOSION_WIDTH, EXPLOSION_HEIGHT, explosionData[0], explosionPalette);
vdp_bitmapSendData16(BID_EXPLOSION1, EXPLOSION_WIDTH, EXPLOSION_HEIGHT, explosionData[1], explosionPalette);
vdp_bitmapSendData16(BID_EXPLOSION2, EXPLOSION_WIDTH, EXPLOSION_HEIGHT, explosionData[2], explosionPalette);
vdp_bitmapSendData16(BID_EXPLOSION3, EXPLOSION_WIDTH, EXPLOSION_HEIGHT, explosionData[3], explosionPalette);
vdp_bitmapSendData16(BID_EXPLOSION4, EXPLOSION_WIDTH, EXPLOSION_HEIGHT, explosionData[4], explosionPalette);
vdp_bitmapSendData16(BID_EXPLOSION5, EXPLOSION_WIDTH, EXPLOSION_HEIGHT, explosionData[5], explosionPalette);
vdp_bitmapSendData16(BID_EXPLOSION6, EXPLOSION_WIDTH, EXPLOSION_HEIGHT, explosionData[6], explosionPalette);
vdp_bitmapSendData16(BID_EXPLOSION7, EXPLOSION_WIDTH, EXPLOSION_HEIGHT, explosionData[7], explosionPalette);
// Eggs use bitmaps 16 to 22
//vdp_bitmapSendData(BID_EGGS0, EGGS_WIDTH, EGGS_HEIGHT, eggsData[0]);
//vdp_bitmapSendData(BID_EGGS1, EGGS_WIDTH, EGGS_HEIGHT, eggsData[1]);
//vdp_bitmapSendData(BID_EGGS2, EGGS_WIDTH, EGGS_HEIGHT, eggsData[2]);
//vdp_bitmapSendData(BID_EGGS3, EGGS_WIDTH, EGGS_HEIGHT, eggsData[3]);
//vdp_bitmapSendData(BID_EGGS4, EGGS_WIDTH, EGGS_HEIGHT, eggsData[4]);
//vdp_bitmapSendData(BID_EGGS5, EGGS_WIDTH, EGGS_HEIGHT, eggsData[5]);
//vdp_bitmapSendData(BID_EGGS6, EGGS_WIDTH, EGGS_HEIGHT, eggsData[6]);
vdp_bitmapSendData16(BID_EGGS0, EGGS_WIDTH, EGGS_HEIGHT, eggsData[0], eggsPalette);
vdp_bitmapSendData16(BID_EGGS1, EGGS_WIDTH, EGGS_HEIGHT, eggsData[1], eggsPalette);
vdp_bitmapSendData16(BID_EGGS2, EGGS_WIDTH, EGGS_HEIGHT, eggsData[2], eggsPalette);
vdp_bitmapSendData16(BID_EGGS3, EGGS_WIDTH, EGGS_HEIGHT, eggsData[3], eggsPalette);
vdp_bitmapSendData16(BID_EGGS4, EGGS_WIDTH, EGGS_HEIGHT, eggsData[4], eggsPalette);
vdp_bitmapSendData16(BID_EGGS5, EGGS_WIDTH, EGGS_HEIGHT, eggsData[5], eggsPalette);
vdp_bitmapSendData16(BID_EGGS6, EGGS_WIDTH, EGGS_HEIGHT, eggsData[6], eggsPalette);
vdp_bitmapSendData16(BID_EGGS7, EGGS_WIDTH, EGGS_HEIGHT, eggsData[7], eggsPalette);
// Small enemy birds use bitmaps 23 to 29
/* vdp_bitmapSendData(BID_SBIRD0, SBIRD_WIDTH, SBIRD_HEIGHT, sbirdData[0]);
vdp_bitmapSendData(BID_SBIRD1, SBIRD_WIDTH, SBIRD_HEIGHT, sbirdData[1]);
vdp_bitmapSendData(BID_SBIRD2, SBIRD_WIDTH, SBIRD_HEIGHT, sbirdData[2]);
vdp_bitmapSendData(BID_SBIRD3, SBIRD_WIDTH, SBIRD_HEIGHT, sbirdData[3]);
vdp_bitmapSendData(BID_SBIRD4, SBIRD_WIDTH, SBIRD_HEIGHT, sbirdData[4]);
vdp_bitmapSendData(BID_SBIRD5, SBIRD_WIDTH, SBIRD_HEIGHT, sbirdData[5]);
vdp_bitmapSendData(BID_SBIRD6, SBIRD_WIDTH, SBIRD_HEIGHT, sbirdData[6]); */
vdp_bitmapSendData16(BID_SBIRD0, SBIRD_WIDTH, SBIRD_HEIGHT, sbirdData[0], sbirdPalette);
vdp_bitmapSendData16(BID_SBIRD1, SBIRD_WIDTH, SBIRD_HEIGHT, sbirdData[1], sbirdPalette);
vdp_bitmapSendData16(BID_SBIRD2, SBIRD_WIDTH, SBIRD_HEIGHT, sbirdData[2], sbirdPalette);
vdp_bitmapSendData16(BID_SBIRD3, SBIRD_WIDTH, SBIRD_HEIGHT, sbirdData[3], sbirdPalette);
vdp_bitmapSendData16(BID_SBIRD4, SBIRD_WIDTH, SBIRD_HEIGHT, sbirdData[4], sbirdPalette);
vdp_bitmapSendData16(BID_SBIRD5, SBIRD_WIDTH, SBIRD_HEIGHT, sbirdData[5], sbirdPalette);
vdp_bitmapSendData16(BID_SBIRD6, SBIRD_WIDTH, SBIRD_HEIGHT, sbirdData[6], sbirdPalette);
// Enemy bullet at bitmap 30
vdp_bitmapSendData(BID_ENEMYBULLET, 16, 16, enemyBulletData);
// Big enemy birds use bitmaps 31 to 37
/* vdp_bitmapSendData(BID_BBIRD0, BBIRD_WIDTH, BBIRD_HEIGHT, bbirdData[0]);
vdp_bitmapSendData(BID_BBIRD1, BBIRD_WIDTH, BBIRD_HEIGHT, bbirdData[1]);
vdp_bitmapSendData(BID_BBIRD2, BBIRD_WIDTH, BBIRD_HEIGHT, bbirdData[2]);
vdp_bitmapSendData(BID_BBIRD3, BBIRD_WIDTH, BBIRD_HEIGHT, bbirdData[3]);
vdp_bitmapSendData(BID_BBIRD4, BBIRD_WIDTH, BBIRD_HEIGHT, bbirdData[4]);
vdp_bitmapSendData(BID_BBIRD5, BBIRD_WIDTH, BBIRD_HEIGHT, bbirdData[5]);
vdp_bitmapSendData(BID_BBIRD6, BBIRD_WIDTH, BBIRD_HEIGHT, bbirdData[6]);
*/
vdp_bitmapSendData16(BID_BBIRD0, BBIRD_WIDTH, BBIRD_HEIGHT, bbirdData[0], bbirdPalette);
vdp_bitmapSendData16(BID_BBIRD1, BBIRD_WIDTH, BBIRD_HEIGHT, bbirdData[1], bbirdPalette);
vdp_bitmapSendData16(BID_BBIRD2, BBIRD_WIDTH, BBIRD_HEIGHT, bbirdData[2], bbirdPalette);
vdp_bitmapSendData16(BID_BBIRD3, BBIRD_WIDTH, BBIRD_HEIGHT, bbirdData[3], bbirdPalette);
vdp_bitmapSendData16(BID_BBIRD4, BBIRD_WIDTH, BBIRD_HEIGHT, bbirdData[4], bbirdPalette);
vdp_bitmapSendData16(BID_BBIRD5, BBIRD_WIDTH, BBIRD_HEIGHT, bbirdData[5], bbirdPalette);
vdp_bitmapSendData16(BID_BBIRD6, BBIRD_WIDTH, BBIRD_HEIGHT, bbirdData[6], bbirdPalette);
// Title sprite characters use bitmaps 38 to 46
//vdp_bitmapSendData(BID_TITLE0, TITLE_WIDTH, TITLE_HEIGHT, titleData[0]);
//vdp_bitmapSendData(BID_TITLE1, TITLE_WIDTH, TITLE_HEIGHT, titleData[1]);
//vdp_bitmapSendData(BID_TITLE2, TITLE_WIDTH, TITLE_HEIGHT, titleData[2]);
//vdp_bitmapSendData(BID_TITLE3, TITLE_WIDTH, TITLE_HEIGHT, titleData[3]);
//vdp_bitmapSendData(BID_TITLE4, TITLE_WIDTH, TITLE_HEIGHT, titleData[4]);
//vdp_bitmapSendData(BID_TITLE5, TITLE_WIDTH, TITLE_HEIGHT, titleData[5]);
//vdp_bitmapSendData(BID_TITLE6, TITLE_WIDTH, TITLE_HEIGHT, titleData[6]);
//vdp_bitmapSendData(BID_TITLE7, TITLE_WIDTH, TITLE_HEIGHT, titleData[7]);
//vdp_bitmapSendData(BID_TITLE8, TITLE_WIDTH, TITLE_HEIGHT, titleData[8]);
vdp_bitmapSendData16(BID_TITLE0, TITLE_WIDTH, TITLE_HEIGHT, titleData[0], titlePalette);
vdp_bitmapSendData16(BID_TITLE1, TITLE_WIDTH, TITLE_HEIGHT, titleData[1], titlePalette);
vdp_bitmapSendData16(BID_TITLE2, TITLE_WIDTH, TITLE_HEIGHT, titleData[2], titlePalette);
vdp_bitmapSendData16(BID_TITLE3, TITLE_WIDTH, TITLE_HEIGHT, titleData[3], titlePalette);
vdp_bitmapSendData16(BID_TITLE4, TITLE_WIDTH, TITLE_HEIGHT, titleData[4], titlePalette);
vdp_bitmapSendData16(BID_TITLE5, TITLE_WIDTH, TITLE_HEIGHT, titleData[5], titlePalette);
vdp_bitmapSendData16(BID_TITLE6, TITLE_WIDTH, TITLE_HEIGHT, titleData[6], titlePalette);
vdp_bitmapSendData16(BID_TITLE7, TITLE_WIDTH, TITLE_HEIGHT, titleData[7], titlePalette);
vdp_bitmapSendData16(BID_TITLE8, TITLE_WIDTH, TITLE_HEIGHT, titleData[8], titlePalette);
// Explosion100 sprite uses bitmaps 38 to 46
//vdp_bitmapSendData(BID_EXPLOSION100_0, EXPLOSION100_WIDTH, EXPLOSION100_HEIGHT, explosion100Data[0]);
//vdp_bitmapSendData(BID_EXPLOSION100_1, EXPLOSION100_WIDTH, EXPLOSION100_HEIGHT, explosion100Data[1]);
//vdp_bitmapSendData(BID_EXPLOSION100_2, EXPLOSION100_WIDTH, EXPLOSION100_HEIGHT, explosion100Data[2]);
//vdp_bitmapSendData(BID_EXPLOSION100_3, EXPLOSION100_WIDTH, EXPLOSION100_HEIGHT, explosion100Data[3]);
//vdp_bitmapSendData(BID_EXPLOSION100_4, EXPLOSION100_WIDTH, EXPLOSION100_HEIGHT, explosion100Data[4]);
//vdp_bitmapSendData(BID_EXPLOSION100_5, EXPLOSION100_WIDTH, EXPLOSION100_HEIGHT, explosion100Data[5]);
//vdp_bitmapSendData(BID_EXPLOSION100_6, EXPLOSION100_WIDTH, EXPLOSION100_HEIGHT, explosion100Data[6]);
//vdp_bitmapSendData(BID_EXPLOSION100_7, EXPLOSION100_WIDTH, EXPLOSION100_HEIGHT, explosion100Data[7]);
//vdp_bitmapSendData(BID_EXPLOSION100_8, EXPLOSION100_WIDTH, EXPLOSION100_HEIGHT, explosion100Data[8]);
vdp_bitmapSendData16(BID_EXPLOSION100_0, EXPLOSION100_WIDTH, EXPLOSION100_HEIGHT, explosion100Data[0], explosion100Palette);
vdp_bitmapSendData16(BID_EXPLOSION100_1, EXPLOSION100_WIDTH, EXPLOSION100_HEIGHT, explosion100Data[1], explosion100Palette);
vdp_bitmapSendData16(BID_EXPLOSION100_2, EXPLOSION100_WIDTH, EXPLOSION100_HEIGHT, explosion100Data[2], explosion100Palette);
vdp_bitmapSendData16(BID_EXPLOSION100_3, EXPLOSION100_WIDTH, EXPLOSION100_HEIGHT, explosion100Data[3], explosion100Palette);
vdp_bitmapSendData16(BID_EXPLOSION100_4, EXPLOSION100_WIDTH, EXPLOSION100_HEIGHT, explosion100Data[4], explosion100Palette);
vdp_bitmapSendData16(BID_EXPLOSION100_5, EXPLOSION100_WIDTH, EXPLOSION100_HEIGHT, explosion100Data[5], explosion100Palette);
vdp_bitmapSendData16(BID_EXPLOSION100_6, EXPLOSION100_WIDTH, EXPLOSION100_HEIGHT, explosion100Data[6], explosion100Palette);
vdp_bitmapSendData16(BID_EXPLOSION100_7, EXPLOSION100_WIDTH, EXPLOSION100_HEIGHT, explosion100Data[7], explosion100Palette);
vdp_bitmapSendData16(BID_EXPLOSION100_8, EXPLOSION100_WIDTH, EXPLOSION100_HEIGHT, explosion100Data[8], explosion100Palette);
// Fragment 8x8 sprites
vdp_bitmapSendData16(BID_FRAGMENT0, FRAGMENT_WIDTH, FRAGMENT_HEIGHT, fragmentData[0], fragmentDataPalette);
vdp_bitmapSendData16(BID_FRAGMENT1, FRAGMENT_WIDTH, FRAGMENT_HEIGHT, fragmentData[1], fragmentDataPalette);
vdp_bitmapSendData16(BID_FRAGMENT2, FRAGMENT_WIDTH, FRAGMENT_HEIGHT, fragmentData[2], fragmentDataPalette);
vdp_bitmapSendData16(BID_FRAGMENT3, FRAGMENT_WIDTH, FRAGMENT_HEIGHT, fragmentData[3], fragmentDataPalette);
}
// Setup audio channels
void SetupAudio()
{
// Channel allocation:
// 0 - Player fire
// 1.- Enemy fire
// 2 - Player explosion
// 3 - Enemy explosion
// 4.- Extra life
UINT8 i;
// Enable extra audio channels as needed
for (i = 3; i < SFX_COUNT; i++)
audio_enableChannel(i);
// Channel 0 - Player fire
audio_setWaveform(SFX_PLAYERFIRE, WAVE_SAW);
audio_setVolumeEnvelope(SFX_PLAYERFIRE, 20, 200, 64, 50);
// Channel 1 - Enamy fire
audio_setWaveform(SFX_ENEMYFIRE, WAVE_SINE);
audio_setVolumeEnvelope(SFX_ENEMYFIRE, 10, 100, 64, 50);
// Channel 2 - Player explosion
audio_setVolumeEnvelope(SFX_PLAYEREXPLODE, 50, 2000, 64, 50);
audio_setWaveform(SFX_PLAYEREXPLODE, WAVE_NOISE);
// Channel 3 - Enemy explosion
audio_setVolumeEnvelope(SFX_ENEMYEXPLODE, 20, 200, 64, 50);
audio_setWaveform(SFX_ENEMYEXPLODE, WAVE_NOISE);
// Channel 4 - Enemy split
audio_setWaveform(SFX_ENEMYSPLIT, WAVE_TRI);
//audio_setVolumeEnvelope(SFX_ENEMYSPLIT, 10, 100, 64, 50);
// Channel 5 - Extra life
audio_setWaveform(SFX_EXTRALIFE, WAVE_SQUARE);
audio_setVolumeEnvelope(SFX_EXTRALIFE, 10, 100, 64, 50);
}
// Redraw the lives display
void UpdateLivesDisplay()
{
vdp_cursorGoto(15, 0);
printf("LIFE %u", lives);
}
// Add to score, award extra life if necessary
void AddScore(unsigned int amount)
{
unsigned int extraLifeBefore = score / FREE_LIFE_INTERVAL;
score += amount;
// If going over a 5000-point boundary, award an extra life
if ((score / FREE_LIFE_INTERVAL) > extraLifeBefore)
{
// Play extra life sound
audio_playNote(SFX_EXTRALIFE, 100, 500, 1000);
lives++;
UpdateLivesDisplay();
}
}
// Redraw the score display
void UpdateScoreDisplay()
{
vdp_cursorGoto(0, 0);
printf("SCORE %u", score);
}
void UpdateLevelDisplay(UINT8 level)
{
vdp_cursorGoto(30, 0);
printf("LEVEL %u ", level + 1);
}
// Show the title sequence
void DoTitle()
{
UINT8 i, keycode, startCount;
float r = 0.0f;
float dy;
// Set up sprites
for (i = 0; i < MAX_SPRITES; i++)
{
vdp_spriteHide(i);
}
vdp_cls();
for (i = 0; i < TITLE_FRAME_COUNT; i++)
{
objects[i].type = 0;
objects[i].x = i * 16 + 68;
objects[i].y = SCREEN_HEIGHT / 3;
vdp_spriteSelect(i);
vdp_spriteClearFramesSelected();
vdp_spriteAddFrameSelected(BID_TITLE0 + i);
vdp_spriteShowSelected();
vdp_spriteMoveToSelected(objects[i].x, objects[i].y);
}
vdp_spriteActivateTotal(9);
vdp_spriteRefresh();
vdp_cursorGoto(10, 20);
printf("BY JUM HIG 2023");
vdp_cursorGoto(8, 22);
printf("PRESS SPACE TO START");
// Wait for keypress
startCount = 255;
while (startCount > 2)
{
waitvblank();
r += 0.03;
for (i = 0; i < TITLE_FRAME_COUNT; i++)
{
dy = sin(r + ((float)i * 0.1f)) * 24.0f;
vdp_spriteMoveTo(i, objects[i].x, objects[i].y + (int)dy);
}
vdp_spriteRefresh();
//keycode = getsysvar_keyascii();
//if (32 == keycode && 255 == startCount)
if (255 == startCount && IsKeyPressed(0xC, 0x4))
startCount = SCREEN_HEIGHT;
// Scroll screen up after we have pressed start
if (startCount < 255)
{
vdp_scroll(0, 3, 2);
vdp_plotColour(rand255() & 0x0F);
vdp_plotPoint(rand() % SCREEN_WIDTH, SCREEN_HEIGHT - 1);
for (i = 0; i < TITLE_FRAME_COUNT; i++)
objects[i].y -= 2;
startCount -= 2;
}
}
}
// Helper function - get number of enemies for a specific level
UINT8 GetNumEnemiesPerLevel(UINT level)
{
UINT8 numEnemies;
numEnemies = 6 + (level / 4);
if (numEnemies > MAX_ENEMIES)
numEnemies = MAX_ENEMIES;
return numEnemies;
}
// Setup the sprites according to the level
void SetupSprites(UINT8 level)
{
UINT8 i;
UINT8 numEnemies;
for (i = 1; i < MAX_SPRITES; i++)
{
vdp_spriteHide(i);
}
// Set up player sprite
vdp_spriteSelect(0);
vdp_spriteClearFramesSelected();
vdp_spriteAddFrameSelected(BID_PLAYER0);
vdp_spriteAddFrameSelected(BID_PLAYER1);
vdp_spriteAddFrameSelected(BID_PLAYER2);
vdp_spriteAddFrameSelected(BID_PLAYER3);
vdp_spriteShowSelected();
vdp_spriteMoveToSelected(SCREEN_WIDTH / 2, SCREEN_HEIGHT - 20);
objects[PLAYER].type = PLAYER;
objects[PLAYER].x = SCREEN_WIDTH / 2;
objects[PLAYER].y = SCREEN_HEIGHT - 30; // Leave gap below so player can see enemies below
objects[PLAYER].state = ST_ACTIVE;
// Set up player bullet sprite
vdp_spriteSelect(1);
vdp_spriteClearFramesSelected();
vdp_spriteAddFrameSelected(BID_PLAYERBULLET);
vdp_spriteHideSelected();
vdp_spriteMoveToSelected(SCREEN_WIDTH / 2, SCREEN_HEIGHT); // Offscreen
objects[PLAYERBULLET].type = PLAYERBULLET;
objects[PLAYERBULLET].x = SCREEN_WIDTH / 2;
objects[PLAYERBULLET].y = SCREEN_HEIGHT;
objects[PLAYERBULLET].state = ST_INACTIVE;
// Set up enemy bullet sprites
for (i = FIRSTENEMYBULLETID; i <= LASTENEMYBULLETID; i++)
{
objects[i].type = ENEMYBULLET;
objects[i].x = 0;
objects[i].y = SCREEN_HEIGHT;
objects[i].state = ST_INACTIVE;
objects[i].frame = 0;
objects[i].counter = 0;
vdp_spriteSelect(i);
vdp_spriteClearFramesSelected();
vdp_spriteAddFrameSelected(BID_ENEMYBULLET);
vdp_spriteAddFrameSelected(BID_FRAGMENT0); // "fragment"
vdp_spriteAddFrameSelected(BID_FRAGMENT1);
vdp_spriteAddFrameSelected(BID_FRAGMENT2);
vdp_spriteAddFrameSelected(BID_FRAGMENT3);
vdp_spriteHideSelected();
vdp_spriteMoveToSelected(SCREEN_WIDTH / 2, SCREEN_HEIGHT); // Offscreen
}
// Set up enemy bird sprites
// Number of enemies increases every time you defeat level 4
numEnemies = GetNumEnemiesPerLevel(level);
// We have to set up animation frames for all possible enemy sprites, so that we
// can spawn additional enemies during gameplay
for (i = FIRSTENEMYID; i <= LASTENEMYID; i++)
{
if (i < FIRSTENEMYID + numEnemies)
{
// Active enemy for this level
objects[i].type = EGG;
objects[i].x = (rand() % (SCREEN_WIDTH - 20)) + 10;
objects[i].y = (i - FIRSTENEMYID) * 20;
objects[i].state = ST_EGG; //(rand255() > 127) ? ST_MOVELEFT : ST_MOVERIGHT;
}
else
{
// Active enemy "slot" for this level
objects[i].type = BIRD;
objects[i].x = 0;
objects[i].y = SCREEN_HEIGHT;
objects[i].state = ST_INACTIVE;
}
objects[i].frame = 0;
objects[i].counter = 0;
vdp_spriteSelect(i);
vdp_spriteClearFramesSelected();
vdp_spriteAddFrameSelected(BID_EGGS0); // Frame 0 to 7 = eggs
vdp_spriteAddFrameSelected(BID_EGGS1);
vdp_spriteAddFrameSelected(BID_EGGS2);
vdp_spriteAddFrameSelected(BID_EGGS3);
vdp_spriteAddFrameSelected(BID_EGGS4);
vdp_spriteAddFrameSelected(BID_EGGS5);
vdp_spriteAddFrameSelected(BID_EGGS6);
vdp_spriteAddFrameSelected(BID_EGGS7);
vdp_spriteAddFrameSelected(BID_SBIRD0); // frame 8 to 14 = small bird
vdp_spriteAddFrameSelected(BID_SBIRD1);
vdp_spriteAddFrameSelected(BID_SBIRD2);
vdp_spriteAddFrameSelected(BID_SBIRD3);
vdp_spriteAddFrameSelected(BID_SBIRD4);
vdp_spriteAddFrameSelected(BID_SBIRD5);
vdp_spriteAddFrameSelected(BID_SBIRD6);
vdp_spriteAddFrameSelected(BID_BBIRD0); // frame 15 to 22 = big bird
vdp_spriteAddFrameSelected(BID_BBIRD1);
vdp_spriteAddFrameSelected(BID_BBIRD2);
vdp_spriteAddFrameSelected(BID_BBIRD3);
vdp_spriteAddFrameSelected(BID_BBIRD4);
vdp_spriteAddFrameSelected(BID_BBIRD5);
vdp_spriteAddFrameSelected(BID_BBIRD6);
vdp_spriteAddFrameSelected(BID_EXPLOSION0); // frame 23 to 31 = small explosion
vdp_spriteAddFrameSelected(BID_EXPLOSION1);
vdp_spriteAddFrameSelected(BID_EXPLOSION2);
vdp_spriteAddFrameSelected(BID_EXPLOSION3);
vdp_spriteAddFrameSelected(BID_EXPLOSION4);
vdp_spriteAddFrameSelected(BID_EXPLOSION5);
vdp_spriteAddFrameSelected(BID_EXPLOSION6);
vdp_spriteAddFrameSelected(BID_EXPLOSION7);
vdp_spriteAddFrameSelected(BID_EXPLOSION7); // doubled to make 9 frames
vdp_spriteAddFrameSelected(BID_EXPLOSION100_0); // frame 32 to 40 = explosion100 (sideways explosion)
vdp_spriteAddFrameSelected(BID_EXPLOSION100_1);
vdp_spriteAddFrameSelected(BID_EXPLOSION100_2);
vdp_spriteAddFrameSelected(BID_EXPLOSION100_3);
vdp_spriteAddFrameSelected(BID_EXPLOSION100_4);
vdp_spriteAddFrameSelected(BID_EXPLOSION100_5);
vdp_spriteAddFrameSelected(BID_EXPLOSION100_6);
vdp_spriteAddFrameSelected(BID_EXPLOSION100_7);
vdp_spriteAddFrameSelected(BID_EXPLOSION100_8);
vdp_spriteSetFrameSelected(objects[i].frame);
if (i < FIRSTENEMYID + numEnemies)
vdp_spriteShowSelected(); // Only show the inital number of enemies starting this level
}
}
// Change an object's direction
UINT8 GetRandomDirection()
{
UINT8 LR;
UINT8 UD;
// Choose random left/right
LR = rand255() & 0x03;
if (3 == LR)
LR = 0;
// Choose random up/down
UD = rand255() & 0x0C;
if (0x0C == UD)
UD = 0;
return (UD | LR);
}
// Kill the player
void KillPLayer()
{
UINT8 i;
// Kill the player
audio_playNote(SFX_PLAYEREXPLODE, 120, 70, 10);
objects[PLAYER].state = ST_DYING; // Start dying animation
objects[PLAYER].counter = 0;
// Spawn some fragments
for (i = FIRSTENEMYBULLETID; i <= LASTENEMYBULLETID; i++)
{
objects[i].type = FRAGMENT;
objects[i].state = ST_FRAGMENT;
objects[i].x = objects[PLAYER].x;
objects[i].y = objects[PLAYER].y;
objects[i].frame = 1; // Bullet frames 1 to 4 are fragment bitmaps
objects[i].counter = 0;
objects[i].dirn = rand() & 0xFF; // random direction
vdp_spriteMoveTo(i, objects[i].x, objects[i].y);
vdp_spriteShow(i);
}
}
// Drop a new enemy bullet
void DropEnemyBullet(OBJECT *pParentObject)
{
UINT8 n;
OBJECT *pBulletObject;
if (!pParentObject)
return;
// Don't allow enemies to fire from too low
if (pParentObject->y > (SCREEN_HEIGHT - 60))
return;
// Find first inactive enemy bullet object/sprite
for (n = FIRSTENEMYBULLETID; n <= LASTENEMYBULLETID; n++)
{
pBulletObject = &objects[n];
if (ST_INACTIVE == pBulletObject->state)
{
// Set up new enemy bullet
audio_playNote(SFX_ENEMYFIRE, 75, 1024, 10);
pBulletObject->type = ENEMYBULLET;
pBulletObject->state = ST_ACTIVE;
pBulletObject->frame = 0;
pBulletObject->x = (BIGBIRD == pParentObject->type) ? pParentObject->x + 8 : pParentObject->x;
pBulletObject->y = pParentObject->y + 16;
vdp_spriteMoveTo(n, pBulletObject->x, pBulletObject->y);
vdp_spriteShow(n);
break; // don't fire multiple bullets!
}
}
}
// Update enemy bullet
void UpdateEnemyBullet(UINT8 n, UINT8 level)
{
UINT8 d = 0;
UINT16 f2;
UINT16 f4;
OBJECT *pObject = &objects[n];
if (ST_ACTIVE == pObject->state)
{
pObject->counter++;
// Hit player?
// Note: Enemy bullet hitpoint = 8, 3, and enemy bullet sprite width = player sprite width
if (pObject->y > objects[PLAYER].y && pObject->y < (objects[PLAYER].y + 16))
{
if (abs(pObject->x - objects[PLAYER].x) < 9)
{
// Kill the player
KillPLayer();
pObject->y = SCREEN_HEIGHT; // kill this bullet below
}
}
if (level < 4)
pObject->y += 1;
else
pObject->y += 2;
if (pObject->y >= SCREEN_HEIGHT)
{
pObject->counter = 0;
pObject->frame = 0;
pObject->state = ST_INACTIVE;
vdp_spriteHide(n);
}
}
else if (ST_FRAGMENT == pObject->state) // A particle effects fragment
{
pObject->counter++;
if (pObject->counter < 126)
{
if (pObject->counter & 1) // update fragment slower
{
if (0 == pObject->dirn)
pObject->dirn = rand() & 0xFF; // Fix random case where fragment does not move
pObject->x += (pObject->dirn & 0x07) - 4;
pObject->y -= ((pObject->dirn & 0x70) >> 5);
pObject->frame = 1 + (pObject->counter >> 5);
}
}
else
{
pObject->counter = 0;
pObject->frame = 0;
pObject->state = ST_INACTIVE;
vdp_spriteHide(n);
}
}
// Update sprite on screen
if (pObject->state != ST_INACTIVE)
{
vdp_spriteMoveTo(n, pObject->x, pObject->y);
vdp_spriteSetFrame(n, pObject->frame);
}
}
// Update enemy according to it's current behaviour
void UpdateEnemy(UINT8 n, UINT8 level)
{
UINT8 d = 0;
UINT8 i;
UINT16 f2;
UINT16 f4;
OBJECT *pObject = &objects[n];
OBJECT *pEnemyObject = NULL;
pObject->counter++;
f2 = (pObject->counter >> 1) & 1; // every 2nd frame
f4 = (pObject->counter >> 2) & 1; // every 4th frame
switch (pObject->state)
{
case ST_EGG :
if (256 == pObject->counter)
{
// First 2 levels of every round, egg hatches to small bird
if (level & 0x2)
pObject->type = BIGBIRD;
else
pObject->type = BIRD;
pObject->state = ST_MOVERANDOM;
pObject->dirn = GetRandomDirection();
pObject->frame = SBIRD_STARTFRAME;
pObject->counter = rand255(); //0;
}
else
{
// Update egg animation frame
pObject->frame = EGG_STARTFRAME + ((UINT8)pObject->counter >> 5);
}
break;
// case ST_MOVERIGHT :
// pObject->x++;
// if (pObject->x == 319)
// pObject->state = ST_MOVELEFT;
//
// pObject->frame = 7 + ((UINT8)(pObject->counter / 8) % 7);\
// break;
// case ST_MOVELEFT :
// pObject->x--;
// if (pObject->x == 0)
// pObject->state = ST_MOVERIGHT;
//
// pObject->frame = 7 + ((UINT8)(pObject->counter / 8) % 7);
// break;
case ST_MOVERANDOM :
// Move counter frames in the current object "direction"
// Dirn is 4-bit bitmask for left/right/up/down bits
d = pObject->dirn;
if (d & DIRN_LEFT)
{
pObject->x--;
if (pObject->x < 10)
pObject->dirn = (d & 0x0C) | DIRN_RIGHT; // Bounce off left edge of screen
}
else if (d & DIRN_RIGHT)
{
pObject->x++;
if (pObject->x > (SCREEN_WIDTH - 32))
pObject->dirn = (d & 0x0C) | DIRN_LEFT; // Bounce off right edge of screen
}
// Only process y movement every 2nd frame (half-speed y movement)
if (f4)
{
if (d & DIRN_UP)
{
pObject->y--;
if (pObject->y < 5)
{
pObject->dirn = DIRN_DOWN; //(d & 0x03) | DIRN_DOWN; // Bounce bird off top of screen
}
}
else if (d & DIRN_DOWN)
{
pObject->y++;
// If bird goes off bottom of screen, then put back at top
// and set it's direction to downwards
if (pObject->y > SCREEN_HEIGHT)
{
pObject->y = 0;
pObject->dirn = DIRN_DOWN;
if (pObject->x < 40)
pObject->dirn |= DIRN_RIGHT;
else if (pObject->x > SCREEN_WIDTH - 40)
pObject->dirn |= DIRN_LEFT;
pObject->counter = 0;
}
}
}
if (BIGBIRD == pObject->type)
pObject->frame = BBIRD_STARTFRAME + ((UINT8)(pObject->counter / 8) % 7);
else
pObject->frame = SBIRD_STARTFRAME + ((UINT8)(pObject->counter / 8) % 7);
// Time to choose a new direction?
if ((pObject->counter % 64) == 0)
{
pObject->dirn = GetRandomDirection(); // up/down/left/right bitmask
}
// Time to fire a bullet / drop a bomb?
if (BIRD == pObject->type && rand() < bombDropChance)
DropEnemyBullet(pObject);
else if (BIGBIRD == pObject->type && rand() < (bombDropChance * 2)) // Big birds drop twice as many bombs
DropEnemyBullet(pObject);
// Small bird grows to big bird? (level 2/4 only)
if (BIRD == pObject->type && 0x400 == pObject->counter && (level & 0x3) == 1)
{
pObject->type = BIGBIRD;
pObject->counter = rand255();
}
// Big bird splits into 2 small birds? (level 3/4 only)
if (BIGBIRD == pObject->type && 0x400 == pObject->counter && (level & 0x3) == 2)
{
// First see if we can spawn another bird
for (i = FIRSTENEMYID; i <= LASTENEMYID; i++)
{
if (i == n)
continue;
pEnemyObject = &objects[i];