mirror of
https://github.com/sehugg/8bitworkshop.git
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665 lines
17 KiB
C
665 lines
17 KiB
C
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/*
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Demonstration game.
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For more information, see "Making Arcade Games in C".
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*/
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#include <stdlib.h>
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#include <string.h>
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#include <cv.h>
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#include <cvu.h>
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#include "common.h"
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//#link "common.c"
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#include "stars.h"
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//#link "stars.c"
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// for SMS
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//#link "fonts.s"
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#define NSPRITES 16
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#define NMISSILES 8
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#define YOFFSCREEN 239
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static byte pattern_table[8*2] = {
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/*{w:16,h:8,brev:1,remap:[-4,0,1,2]}*/
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0xCC, 0xF2, 0xD0, 0xFC, 0xF3, 0xE8, 0xC4, 0x03,
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0x0C, 0x13, 0x02, 0x0F, 0x33, 0x05, 0x08, 0x30,
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};
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static byte sprite_table[][16*2] = {
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/*{w:16,h:16,brev:1,remap:[4,0,1,2,3,5,6,7,8,9],count:15}*/
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{
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0x01, 0x03, 0x02, 0x01, 0x01, 0x01, 0x01, 0x01,
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0x03, 0x86, 0xCD, 0xBE, 0x9F, 0xB1, 0xC0, 0x80,
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0x80, 0xC0, 0x40, 0x80, 0x80, 0x80, 0x80, 0x80,
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0xC0, 0x61, 0xB3, 0x7D, 0xF9, 0x8D, 0x03, 0x01,
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},{
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0x00, 0x00, 0x01, 0x03, 0x05, 0x01, 0x01, 0x00,
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0x00, 0x00, 0x02, 0x00, 0x01, 0x00, 0x00, 0x00,
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0x00, 0x80, 0xC0, 0xE0, 0xD0, 0xC0, 0xC0, 0x80,
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0xA0, 0x80, 0x40, 0x00, 0x00, 0x00, 0x40, 0x00,
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},{
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0x00, 0x00, 0x02, 0x03, 0x01, 0x01, 0x01, 0x01,
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0x03, 0x07, 0x07, 0x03, 0x03, 0x01, 0x00, 0x00,
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0x00, 0x00, 0x40, 0xC0, 0x80, 0x80, 0x80, 0x80,
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0xC0, 0xE0, 0xE0, 0xC0, 0xC0, 0x80, 0x00, 0x00,
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},{
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0x00, 0x00, 0x00, 0x04, 0x08, 0x11, 0x04, 0x05,
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0x15, 0x24, 0x02, 0x00, 0x08, 0x30, 0x00, 0x00,
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0x00, 0x00, 0x00, 0x08, 0xC4, 0x22, 0x08, 0xE8,
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0xEA, 0xC9, 0x10, 0x00, 0xC4, 0x03, 0x00, 0x00,
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},{
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0x00, 0x00, 0x08, 0x30, 0x01, 0x00, 0x08, 0x0A,
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0x00, 0x09, 0x04, 0x00, 0x10, 0x00, 0x40, 0x00,
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0x00, 0x00, 0x04, 0xC3, 0x20, 0x00, 0x04, 0x14,
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0x00, 0x24, 0x08, 0x00, 0x04, 0xC0, 0x01, 0x00,
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},{
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0x04, 0x10, 0x00, 0x22, 0x00, 0x00, 0x44, 0x02,
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0x00, 0x40, 0x02, 0x24, 0x00, 0x00, 0x48, 0x01,
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0x08, 0x42, 0x00, 0x11, 0x00, 0x80, 0x91, 0x20,
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0x00, 0x00, 0x21, 0x90, 0x82, 0x00, 0x08, 0x21,
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},{ // enemy ship rotations
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0x00, 0x00, 0x00, 0x00, 0x00, 0x0C, 0x13, 0x02,
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0x0F, 0x33, 0x05, 0x08, 0x30, 0x00, 0x00, 0x00,
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0x00, 0x00, 0x00, 0x00, 0x00, 0xCC, 0xF2, 0xD0,
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0xFC, 0xF3, 0xE8, 0xC4, 0x03, 0x00, 0x00, 0x00,
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},{
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0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01, 0x1F,
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0x12, 0x13, 0x03, 0x02, 0x04, 0x18, 0x00, 0x00,
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0x00, 0x00, 0x70, 0x42, 0x4C, 0xF0, 0xBF, 0xF0,
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0xF8, 0xF8, 0xF8, 0xF0, 0x80, 0x80, 0x80, 0x00,
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},{
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0x00, 0x02, 0x04, 0x04, 0x03, 0x02, 0x07, 0x07,
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0x02, 0x03, 0x04, 0x04, 0x02, 0x00, 0x00, 0x00,
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0x48, 0x48, 0x90, 0xA0, 0xC0, 0xE0, 0xF0, 0xF0,
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0xE0, 0xC0, 0xA0, 0x90, 0x48, 0x48, 0x00, 0x00,
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},{
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0x02, 0x12, 0x0A, 0x0A, 0x27, 0x27, 0x3D, 0x07,
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0x07, 0x01, 0x01, 0x01, 0x01, 0x00, 0x00, 0x00,
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0x00, 0x00, 0x00, 0xE0, 0xF0, 0xF0, 0xF0, 0xFE,
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0x60, 0xF0, 0x08, 0x04, 0xC4, 0x00, 0x00, 0x00,
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},{
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0x00, 0x00, 0x00, 0xC0, 0x23, 0x17, 0xCF, 0x3F,
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0x0B, 0x4F, 0x33, 0x00, 0x00, 0x00, 0x00, 0x00,
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0x00, 0x00, 0x00, 0x0C, 0x10, 0xA0, 0xCC, 0xF0,
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0x40, 0xC8, 0x30, 0x00, 0x00, 0x00, 0x00, 0x00,
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},{
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0x00, 0x01, 0x01, 0x01, 0x0F, 0x1F, 0x1F, 0x1F,
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0x0F, 0xFD, 0x0F, 0x32, 0x42, 0x0E, 0x00, 0x00,
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0x00, 0x00, 0x18, 0x20, 0x40, 0xC0, 0xC8, 0x48,
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0xF8, 0x80, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00,
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},{
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0x00, 0x00, 0x12, 0x12, 0x09, 0x05, 0x03, 0x07,
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0x0F, 0x0F, 0x07, 0x03, 0x05, 0x09, 0x12, 0x12,
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0x00, 0x00, 0x00, 0x40, 0x20, 0x20, 0xC0, 0x40,
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0xE0, 0xE0, 0x40, 0xC0, 0x20, 0x20, 0x40, 0x00,
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},{
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0x00, 0x00, 0x00, 0x23, 0x20, 0x10, 0x0F, 0x06,
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0x7F, 0x0F, 0x0F, 0x0F, 0x07, 0x00, 0x00, 0x00,
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0x00, 0x00, 0x00, 0x80, 0x80, 0x80, 0x80, 0xE0,
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0xE0, 0xBC, 0xE4, 0xE4, 0x50, 0x50, 0x48, 0x40,
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},{
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0x00, 0x00, 0x00, 0x00, 0x00, 0x0C, 0x13, 0x02,
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0x0F, 0x33, 0x05, 0x08, 0x30, 0x00, 0x00, 0x00,
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0x00, 0x00, 0x00, 0x00, 0x00, 0xCC, 0xF2, 0xD0,
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0xFC, 0xF3, 0xE8, 0xC4, 0x03, 0x00, 0x00, 0x00,
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}
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};
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#define SPRI_SHIP (4*0)
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#define SPRI_MISSILE (4*1)
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#define SPRI_BOMB (4*2)
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#define SPRI_EXPLODE (4*3)
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#define SPRI_ENEMY (4*6)
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#define COLOR_FORMATION CV_COLOR_LIGHT_GREEN
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#define COLOR_ATTACKER CV_COLOR_LIGHT_RED
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#define COLOR_PLAYER CV_COLOR_LIGHT_YELLOW
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#define COLOR_MISSILE CV_COLOR_WHITE
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#define COLOR_SCORE CV_COLOR_LIGHT_BLUE
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#define COLOR_EXPLOSION CV_COLOR_RED
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// GAME CODE
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typedef struct {
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byte shape;
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} FormationEnemy;
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// should be power of 2 length
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typedef struct {
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byte findex;
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byte shape;
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word x;
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word y;
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byte dir;
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byte returning;
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} AttackingEnemy;
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typedef struct {
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signed char dx;
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byte xpos;
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signed char dy;
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byte ypos;
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} Missile;
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#define ENEMIES_PER_ROW 8
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#define ENEMY_ROWS 4
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#define MAX_IN_FORMATION (ENEMIES_PER_ROW*ENEMY_ROWS)
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#define MAX_ATTACKERS 6
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FormationEnemy formation[MAX_IN_FORMATION];
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AttackingEnemy attackers[MAX_ATTACKERS];
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Missile missiles[NMISSILES];
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struct cvu_sprite vsprites[NSPRITES];
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byte formation_offset_x;
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signed char formation_direction;
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byte current_row;
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byte player_x;
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const byte player_y = 168;
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byte player_exploding;
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byte enemy_exploding;
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byte enemies_left;
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word player_score;
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word framecount;
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void copy_sprites() {
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byte i;
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word ofs;
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cvu_memtovmemcpy(SPRITES, vsprites, sizeof(vsprites));
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// copy all "shadow missiles" to video memory
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ofs = SPRITES + NSPRITES*4;
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for (i=0; i<NMISSILES; i++) {
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// sprite struct: {y, x, name, tag}
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cv_set_write_vram_address(ofs);
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cv_voutb(missiles[i].ypos);
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cv_voutb(missiles[i].xpos);
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ofs += 4;
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}
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}
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void add_score(word bcd) {
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player_score = bcd_add(player_score, bcd);
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draw_bcd_word(0, 0, player_score);
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putcharxy(4, 0, CHAR('0'));
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}
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void clrobjs() {
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byte i;
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word ofs;
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memset(vsprites, 0, sizeof(vsprites));
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for (i=0; i<NSPRITES; i++) {
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vsprites[i].y = YOFFSCREEN;
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}
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ofs = SPRITES + NSPRITES*4;
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for (i=0; i<NMISSILES; i++) {
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// sprite struct: {y, x, name, tag}
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cvu_voutb(i == 7 ? 4 : 8, ofs+2);
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cvu_voutb(CV_COLOR_WHITE, ofs+3);
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ofs += 4;
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missiles[i].ypos = YOFFSCREEN;
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}
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}
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void setup_formation() {
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byte i;
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memset(formation, 0, sizeof(formation));
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memset(attackers, 0, sizeof(attackers));
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for (i=0; i<MAX_IN_FORMATION; i++) {
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byte flagship = i < ENEMIES_PER_ROW;
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formation[i].shape = flagship ? 0x43 : 0x43;
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}
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enemies_left = MAX_IN_FORMATION;
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}
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#define BLANK 0
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void draw_row(byte row) {
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byte i,j;
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byte x = formation_offset_x / 8;
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byte xd = (formation_offset_x & 7) * 3;
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byte y = 3 + row * 2;
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cv_set_write_vram_address(IMAGE + y*32);
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for (i=0; i<x; i++)
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cv_graphics_port = starfield_get_tile_xy(i,y);
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for (i=0; i<ENEMIES_PER_ROW; i++) {
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byte shape = formation[i + row*ENEMIES_PER_ROW].shape;
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if (shape) {
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shape += xd;
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for (j=0; j<3; j++) {
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cv_graphics_port = shape++;
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x++;
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}
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} else {
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for (j=0; j<3; j++) {
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cv_graphics_port = starfield_get_tile_xy(x,y);
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x++;
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}
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}
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}
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for (; x<COLS; x++)
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cv_graphics_port = starfield_get_tile_xy(x,y);
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}
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void draw_next_row() {
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draw_row(current_row);
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if (++current_row == ENEMY_ROWS) {
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current_row = 0;
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formation_offset_x += formation_direction;
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if (formation_offset_x == 71) {
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formation_direction = -1;
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}
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else if (formation_offset_x == 0) {
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formation_direction = 1;
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}
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}
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}
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const byte DIR_TO_CODE[32] = {
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16, 16,
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20, 20, 20, 20,
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24, 24, 24, 24,
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28, 28, 28, 28,
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0, 0, 0, 0,
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4, 4, 4, 4,
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8, 8, 8, 8,
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12, 12, 12, 12,
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16, 16,
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};
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const byte SINTBL[32] = {
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0, 25, 49, 71, 90, 106, 117, 125,
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127, 125, 117, 106, 90, 71, 49, 25,
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0, -25, -49, -71, -90, -106, -117, -125,
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-127, -125, -117, -106, -90, -71, -49, -25,
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};
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signed char isin(byte dir) {
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return SINTBL[dir & 31];
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}
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signed char icos(byte dir) {
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return isin(dir+8);
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}
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#define FORMATION_X0 0
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#define FORMATION_Y0 19
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#define FORMATION_XSPACE 24
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#define FORMATION_YSPACE 16
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byte get_attacker_x(byte formation_index) {
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byte column = (formation_index % ENEMIES_PER_ROW);
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return FORMATION_XSPACE*column + FORMATION_X0 + formation_offset_x;
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}
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byte get_attacker_y(byte formation_index) {
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byte row = formation_index / ENEMIES_PER_ROW;
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return FORMATION_YSPACE*row + FORMATION_Y0;
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}
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void draw_attacker(byte i) {
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AttackingEnemy* a = &attackers[i];
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if (a->findex) {
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vsprites[i].name = SPRI_ENEMY + DIR_TO_CODE[a->dir & 31]; // TODO: code + a->shape + 14;
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vsprites[i].x = a->x >> 8;
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vsprites[i].y = a->y >> 8;
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vsprites[i].tag = COLOR_ATTACKER;
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} else {
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vsprites[i].y = YOFFSCREEN;
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}
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}
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void draw_attackers() {
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byte i;
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for (i=0; i<MAX_ATTACKERS; i++) {
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draw_attacker(i);
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}
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}
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void return_attacker(AttackingEnemy* a) {
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byte fi = a->findex-1;
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byte destx = get_attacker_x(fi);
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byte desty = get_attacker_y(fi);
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byte ydist = desty - (a->y >> 8);
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// are we close to our formation slot?
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if (ydist == 0) {
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// convert back to formation enemy
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formation[fi].shape = a->shape;
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a->findex = 0;
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} else {
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a->dir = (ydist + 16) & 31;
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a->x = destx << 8;
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a->y += 128;
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}
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}
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void fly_attacker(AttackingEnemy* a) {
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a->x += isin(a->dir) * 2;
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a->y += icos(a->dir) * 2;
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if ((a->y >> 8) == 0) {
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a->returning = 1;
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}
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}
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void move_attackers() {
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byte i;
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for (i=0; i<MAX_ATTACKERS; i++) {
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AttackingEnemy* a = &attackers[i];
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if (a->findex) {
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if (a->returning)
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return_attacker(a);
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else
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fly_attacker(a);
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}
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}
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}
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void think_attackers() {
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byte i;
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for (i=0; i<MAX_ATTACKERS; i++) {
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AttackingEnemy* a = &attackers[i];
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if (a->findex) {
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// rotate?
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byte x = a->x >> 8;
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byte y = a->y >> 8;
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// don't shoot missiles after player exploded
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if (y < 112 || player_exploding) {
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if (x < 128) {
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a->dir++;
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} else {
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a->dir--;
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}
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} else {
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// lower half of screen
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// shoot a missile?
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if (missiles[i].ypos == YOFFSCREEN) {
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missiles[i].ypos = y+16;
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missiles[i].xpos = x;
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missiles[i].dy = 2;
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}
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}
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}
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}
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}
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void formation_to_attacker(byte formation_index) {
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byte i;
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// out of bounds? return
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if (formation_index >= MAX_IN_FORMATION)
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return;
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// nobody in formation? return
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if (!formation[formation_index].shape)
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return;
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// find an empty attacker slot
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for (i=0; i<MAX_ATTACKERS; i++) {
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AttackingEnemy* a = &attackers[i];
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if (a->findex == 0) {
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a->x = get_attacker_x(formation_index) << 8;
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a->y = get_attacker_y(formation_index) << 8;
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a->shape = formation[formation_index].shape;
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a->findex = formation_index+1;
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a->dir = 0;
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a->returning = 0;
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formation[formation_index].shape = 0;
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break;
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}
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}
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}
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void draw_player() {
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vsprites[7].x = player_x;
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vsprites[7].y = player_y;
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vsprites[7].name = SPRI_SHIP;
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vsprites[7].tag = COLOR_PLAYER;
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}
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void move_player() {
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struct cv_controller_state state;
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cv_get_controller_state(&state, 0);
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// move left/right?
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if ((state.joystick & CV_LEFT) && player_x > 16) player_x--;
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if ((state.joystick & CV_RIGHT) && player_x < 224) player_x++;
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// shoot missile?
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if ((state.joystick & CV_FIRE_0) && missiles[7].ypos == YOFFSCREEN) {
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missiles[7].ypos = player_y-8; // must be multiple of missile speed
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missiles[7].xpos = player_x; // player X position
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missiles[7].dy = -4; // player missile speed
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}
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|
vsprites[7].x = player_x;
|
|
}
|
|
|
|
void move_missiles() {
|
|
byte i;
|
|
for (i=0; i<8; i++) {
|
|
if (missiles[i].ypos != YOFFSCREEN) {
|
|
// hit the bottom or top?
|
|
if ((byte)(missiles[i].ypos += missiles[i].dy) > YOFFSCREEN) {
|
|
missiles[i].ypos = YOFFSCREEN;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
void blowup_at(byte x, byte y) {
|
|
vsprites[6].tag = COLOR_EXPLOSION;
|
|
vsprites[6].name = SPRI_EXPLODE; // TODO
|
|
vsprites[6].x = x;
|
|
vsprites[6].y = y;
|
|
enemy_exploding = 1;
|
|
}
|
|
|
|
void animate_enemy_explosion() {
|
|
if (enemy_exploding) {
|
|
// animate next frame
|
|
if (enemy_exploding >= 8) {
|
|
enemy_exploding = 0; // hide explosion after 4 frames
|
|
vsprites[6].y = YOFFSCREEN;
|
|
} else {
|
|
vsprites[6].name = SPRI_EXPLODE + (enemy_exploding += 4); // TODO
|
|
}
|
|
}
|
|
}
|
|
|
|
void animate_player_explosion() {
|
|
byte z = player_exploding;
|
|
if (z <= 3) {
|
|
if (z == 3) {
|
|
vsprites[7].y = YOFFSCREEN;
|
|
} else {
|
|
vsprites[7].name = SPRI_EXPLODE + z*4;
|
|
}
|
|
}
|
|
}
|
|
|
|
void hide_player_missile() {
|
|
missiles[7].ypos = YOFFSCREEN;
|
|
}
|
|
|
|
void does_player_shoot_formation() {
|
|
byte mx = missiles[7].xpos + 8;
|
|
byte my = missiles[7].ypos;
|
|
signed char row = (my - FORMATION_Y0) / FORMATION_YSPACE;
|
|
if (row >= 0 && row < ENEMY_ROWS) {
|
|
// ok if unsigned (in fact, must be due to range)
|
|
byte xoffset = mx - FORMATION_X0 - formation_offset_x;
|
|
byte column = xoffset / FORMATION_XSPACE;
|
|
byte localx = xoffset - column * FORMATION_XSPACE;
|
|
if (column < ENEMIES_PER_ROW && localx < 16) {
|
|
char index = column + row * ENEMIES_PER_ROW;
|
|
if (formation[index].shape) {
|
|
formation[index].shape = 0;
|
|
enemies_left--;
|
|
blowup_at(get_attacker_x(index), get_attacker_y(index));
|
|
hide_player_missile();
|
|
add_score(2);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
void does_player_shoot_attacker() {
|
|
byte mx = missiles[7].xpos + 8;
|
|
byte my = missiles[7].ypos;
|
|
byte i;
|
|
for (i=0; i<MAX_ATTACKERS; i++) {
|
|
AttackingEnemy* a = &attackers[i];
|
|
if (a->findex && in_rect(mx, my, a->x >> 8, a->y >> 8, 16, 16)) {
|
|
blowup_at(a->x >> 8, a->y >> 8);
|
|
a->findex = 0;
|
|
enemies_left--;
|
|
hide_player_missile();
|
|
add_score(5);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
void does_missile_hit_player() {
|
|
byte i;
|
|
if (player_exploding)
|
|
return;
|
|
for (i=0; i<MAX_ATTACKERS; i++) {
|
|
if (missiles[i].dy &&
|
|
in_rect(missiles[i].xpos + 8, missiles[i].ypos + 16,
|
|
player_x, player_y, 16, 16)) {
|
|
player_exploding = 1;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
void new_attack_wave() {
|
|
byte i = rand();
|
|
byte j;
|
|
// find a random slot that has an enemy
|
|
for (j=0; j<MAX_IN_FORMATION; j++) {
|
|
i = (i+1) & (MAX_IN_FORMATION-1);
|
|
// anyone there?
|
|
if (formation[i].shape) {
|
|
formation_to_attacker(i);
|
|
formation_to_attacker(i+1);
|
|
formation_to_attacker(i+ENEMIES_PER_ROW);
|
|
formation_to_attacker(i+ENEMIES_PER_ROW+1);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
void new_player_ship() {
|
|
player_exploding = 0;
|
|
player_x = 128;
|
|
draw_player();
|
|
}
|
|
|
|
void set_sounds() {
|
|
byte i;
|
|
// missile fire sound
|
|
if (missiles[7].ypos != YOFFSCREEN) {
|
|
cv_set_frequency(CV_SOUNDCHANNEL_0, 2000-missiles[7].ypos*4);
|
|
cv_set_attenuation(CV_SOUNDCHANNEL_0, 18);
|
|
} else {
|
|
cv_set_attenuation(CV_SOUNDCHANNEL_0, 32);
|
|
}
|
|
// enemy explosion sound
|
|
if (enemy_exploding) {
|
|
cv_set_frequency(CV_SOUNDCHANNEL_1, 500+enemy_exploding*64);
|
|
cv_set_attenuation(CV_SOUNDCHANNEL_1, 14);
|
|
} else {
|
|
cv_set_attenuation(CV_SOUNDCHANNEL_1, 32);
|
|
}
|
|
cv_set_attenuation(CV_SOUNDCHANNEL_2, 32);
|
|
// player explosion
|
|
if (player_exploding && player_exploding < 15) {
|
|
cv_set_frequency(CV_SOUNDCHANNEL_2, player_exploding*256);
|
|
cv_set_attenuation(CV_SOUNDCHANNEL_NOISE, 4+player_exploding);
|
|
cv_set_noise(true, 3);
|
|
} else {
|
|
// set diving sounds for spaceships
|
|
cv_set_attenuation(CV_SOUNDCHANNEL_NOISE, 32);
|
|
for (i=0; i<3; i++) {
|
|
byte y = attackers[i].y >> 8;
|
|
if (y >= 0x80) {
|
|
cv_set_frequency(CV_SOUNDCHANNEL_2, 4000+y*8);
|
|
cv_set_attenuation(CV_SOUNDCHANNEL_2, 28);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
void wait_for_frame() {
|
|
while (((vint_counter ^ framecount) & 3) == 0);
|
|
}
|
|
|
|
void play_round() {
|
|
byte end_timer = 255;
|
|
player_score = 0;
|
|
add_score(0);
|
|
//putstringxy(0, 0, "PLAYER 1");
|
|
setup_formation();
|
|
clrobjs();
|
|
formation_direction = 1;
|
|
vint_counter = 0;
|
|
framecount = 0;
|
|
new_player_ship();
|
|
while (end_timer) {
|
|
if (player_exploding) {
|
|
if ((framecount & 7) == 1) {
|
|
animate_player_explosion();
|
|
if (++player_exploding > 32 && enemies_left) {
|
|
new_player_ship();
|
|
}
|
|
}
|
|
} else {
|
|
if ((framecount & 0x7f) == 0 || enemies_left < 8) {
|
|
new_attack_wave();
|
|
}
|
|
move_player();
|
|
does_missile_hit_player();
|
|
}
|
|
if ((framecount & 3) == 0) animate_enemy_explosion();
|
|
move_attackers();
|
|
move_missiles();
|
|
does_player_shoot_formation();
|
|
does_player_shoot_attacker();
|
|
draw_next_row();
|
|
draw_attackers();
|
|
if ((framecount & 0xf) == 0) think_attackers();
|
|
set_sounds();
|
|
framecount++;
|
|
if (!enemies_left) end_timer--;
|
|
wait_for_frame();
|
|
copy_sprites();
|
|
starfield_update();
|
|
}
|
|
}
|
|
|
|
/*
|
|
PATTERN TABLE:
|
|
0-95 6x8 font, starting at ' '
|
|
67-82 shifted enemy sprites
|
|
*/
|
|
|
|
void setup_graphics() {
|
|
byte i;
|
|
copy_default_character_set();
|
|
cvu_memtovmemcpy(SPRITE_PATTERNS, sprite_table, sizeof(sprite_table));
|
|
cvu_vmemset(COLOR, COLOR_SCORE<<4, 8); // set color for chars 0-63
|
|
cvu_vmemset(COLOR+8, COLOR_FORMATION<<4, 32-8); // set chars 63-255
|
|
for (i=0; i<8; i++)
|
|
set_shifted_pattern(pattern_table, PATTERN+67*8+i*3*8, i);
|
|
}
|
|
|
|
void main() {
|
|
vdp_setup();
|
|
setup_graphics();
|
|
clrscr();
|
|
starfield_setup();
|
|
cv_set_vint_handler(&vint_handler);
|
|
cv_set_screen_active(true);
|
|
play_round();
|
|
main();
|
|
}
|