3 * (C) 2018 by Andreas Eversberg <jolly@eversberg.eu>
6 * This program is free software: you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation, either version 3 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
25 #include <sys/types.h>
26 #include "../libsdl/sdl.h"
27 #include "../libsdl/opengl.h"
28 #include "../libcpu/m68k.h"
29 #include "../libcpu/execute.h"
30 #include "../libvideo/video.h"
31 #include "../libsound/sound.h"
32 #include "../libjoystick/joystick.h"
33 #include "../libkeyboard/keyboard.h"
34 #include "../libdisk/disk.h"
35 #include "mercenary.h"
37 static int config_amiga_speed = 1;
38 static const char *config_gamesave_dir = ".mercenary";
39 static int config_video_filter = 0;
40 static int config_audio_filter = 1;
42 #define CPU_SPEED 7093790.0;
44 #define SOUND_SAMPLERATE 48000
46 * - must be used for sound rendering chunk
49 /* numbe of buffer chunks to dejitter:
50 * - SDL render interval
51 * - sound rendering interval
52 * - sound card interval
53 * 4 should be minimum, if video rate is >=50 Hz
55 #define SOUND_CHUNKS 4
57 /* test sound to check if buffer does not overflow / underrun */
58 //#define DEBUG_SOUND_BUFFERING
60 #define IOSIZE 0x1000 /* bytes in io space */
61 #define MEMORY_SIZE 0x80000
62 static uint8_t *memory = NULL;
63 static uint8_t *image = NULL;
64 #define SCREEN_WIDTH (320*3)
65 #define SCREEN_HEIGHT (200*3)
66 #define IMAGE_WIDTH 320
67 #define IMAGE_HEIGHT 200
68 #define BENSON_AT_LINE 136
69 #define IMAGE_DIWSTART 0x2c
70 static uint16_t *chipreg = NULL;
71 static float *sound_buffer = NULL; /* sound buffer memory */
72 static int sound_buffer_size; /* buffer sample size */
73 static int sound_buffer_writep; /* write pointer at buffer */
74 static int sound_buffer_readp; /* read pointer at buffer */
76 static const char *home_dir;
80 int parse_args(int argc, char *argv[])
85 if (!strcmp(argv[i], "-h") || !strcmp(argv[i], "--help")) {
86 printf("Usage: %s\n", argv[0]);
87 printf(" -s --amiga-speed original | full\n");
88 printf(" Set speed of rendering to original Amiga or full speed.\n");
89 printf(" -v --video-filter on | off\n");
90 printf(" Set video filter.\n");
91 printf(" -a --audio-filter on | off\n");
92 printf(" Set audio filter.\n");
95 if (!strcmp(argv[i], "-s") || !strcmp(argv[i], "--amiga-speed")) {
99 printf("Missing parameter, use '--help'!\n");
102 if (!strcmp(argv[i], "original"))
103 config_amiga_speed = 1;
105 if (!strcmp(argv[i], "full"))
106 config_amiga_speed = 0;
109 printf("Illegal parameter, use '--help'!\n");
113 if (!strcmp(argv[i], "-v") || !strcmp(argv[i], "--video-filter")) {
116 goto missing_parameter;
117 if (!strcmp(argv[i], "on"))
118 config_video_filter = 1;
120 if (!strcmp(argv[i], "off"))
121 config_video_filter = 0;
123 goto illegal_parameter;
125 if (!strcmp(argv[i], "-a") || !strcmp(argv[i], "--audio-filter")) {
128 goto missing_parameter;
129 if (!strcmp(argv[i], "on"))
130 config_audio_filter = 1;
132 if (!strcmp(argv[i], "off"))
133 config_audio_filter = 0;
135 goto illegal_parameter;
137 printf("Illegal option '%s', use '--help'!\n", argv[i]);
146 static void main_loop(void)
148 int had_first_irq = 0;
149 static uint32_t current_time, last_time = 0, diff;
153 double render_delay = 0.0;
154 uint32_t palette_address;
155 uint16_t palette[16];
157 last_time = SDL_GetTicks();
159 /* render result on window */
161 /* STEP 1: let the CPU render/process the game */
162 /* don't render if we still delay */
164 /* execute until the rendered image is ready */
165 cycle_count = execute_cpu(0, mercenary_stop_at);
167 palette_address = mercenary_palette();
168 for (i = 0; i < 16; i++)
169 palette[i] = m68k_read_memory_16(palette_address + i*2);
170 /* for amiga speed: set delay by the number of cycles */
171 if (config_amiga_speed)
172 render_delay = (double)cycle_count / CPU_SPEED;
175 /* STEP 2: render image in memory via OpenGL */
177 /* render game view without benson
178 * because benson is not updated before VBL IRQ, we don't want old image from double buffer
180 emul_video(image, memory, palette, IMAGE_WIDTH, IMAGE_HEIGHT, IMAGE_DIWSTART, chipreg, 0, BENSON_AT_LINE);
185 render_opengl(image, config_video_filter);
188 /* STEP 3: execute interrupt at rate of 50Hz, render sound */
189 current_time = SDL_GetTicks();
190 diff = current_time - last_time;
191 /* in case of timer glitch, execute IRQ only by maximum number of SOUND_CHUNKS */
192 if (diff > 1000 * SOUND_CHUNKS / IRQ_RATE) {
193 diff = 1000 * SOUND_CHUNKS / IRQ_RATE;
194 last_time = current_time - 1000 * SOUND_CHUNKS / IRQ_RATE;
196 while (diff > 1000 / IRQ_RATE) {
197 execute_cpu(3, NULL);
198 execute_cpu(4, NULL);
200 /* render benson without game view
201 * because we only got benson refreshed during VBL IRQ
203 emul_video(image, memory, palette, IMAGE_WIDTH, IMAGE_HEIGHT, IMAGE_DIWSTART, chipreg, BENSON_AT_LINE, IMAGE_HEIGHT);
204 /* render sound to sound buffer
205 * buffer pointer read and write is atomic, so no locking required!
207 space = (sound_buffer_readp - sound_buffer_writep - 1 + sound_buffer_size) % sound_buffer_size;
208 if (space < SOUND_SAMPLERATE / IRQ_RATE) {
209 #ifdef DEBUG_SOUND_BUFFERING
210 fprintf(stderr, "sound buffer overflow\n");
214 length = SOUND_SAMPLERATE / IRQ_RATE;
215 #ifdef DEBUG_SOUND_BUFFERING
216 printf("can write %d, write %d\n", space, length);
219 for (s = 0; s < length; s++) {
220 sound_buffer[(sound_buffer_writep + s) % sound_buffer_size]
221 = sin(2 * M_PI * 999 * cnt / SOUND_SAMPLERATE)
222 * sin(2 * M_PI * 21 * cnt / SOUND_SAMPLERATE)
223 * sin(2 * M_PI * 0.5 * cnt / SOUND_SAMPLERATE);
227 render_sound(memory, sound_buffer, sound_buffer_size, sound_buffer_writep, length, config_audio_filter);
229 sound_buffer_writep = (sound_buffer_writep + length) % sound_buffer_size;
230 diff -= 1000 / IRQ_RATE;
231 last_time += 1000 / IRQ_RATE;
233 /* count down render delay */
235 render_delay -= 1.0 / (double)IRQ_RATE;
236 if (render_delay < 0.0)
243 int main(int argc, char *argv[])
248 home_dir = getenv("HOME");
252 rc = parse_args(argc, argv);
257 image = calloc(IMAGE_WIDTH * IMAGE_HEIGHT, 3);
259 fprintf(stderr, "Failed to allocate image buffer\n");
263 if ((SOUND_SAMPLERATE % IRQ_RATE)) {
264 fprintf(stderr, "Sample rate must be a multiple of IRQ rate, please fix!\n");
267 if ((1000 % IRQ_RATE)) {
268 fprintf(stderr, "1000 (Ticks per second) rate must be a multiple of IRQ rate, please fix!\n");
272 /* calculate SDL chunk size for audio
273 * it must be a power of two, but not more than the chunk size for each IRQ!
275 for (sdl_sound_chunk = 2; sdl_sound_chunk <= (SOUND_SAMPLERATE / IRQ_RATE); sdl_sound_chunk <<= 1)
277 sdl_sound_chunk >>= 1;
278 // printf("samples per IRQ = %d, samples per SDL audio = %d\n", SOUND_SAMPLERATE / IRQ_RATE, sdl_sound_chunk); exit(0);
280 /* allocate sound buffers */
281 sound_buffer_size = SOUND_SAMPLERATE / IRQ_RATE * SOUND_CHUNKS;
282 sound_buffer = calloc(sound_buffer_size, sizeof(*sound_buffer));
284 fprintf(stderr, "Failed to allocate image buffer\n");
288 /* allocate memory */
289 memory = calloc(MEMORY_SIZE, 1);
291 fprintf(stderr, "Failed to allocate cpu's memory\n");
294 chipreg = calloc(IOSIZE, 1);
296 fprintf(stderr, "Failed to allocate chip register\n");
301 execute_init(MEMORY_SIZE, memory, chipreg);
306 /* patch some stuff */
309 /* init SDL and OpenGL */
310 rc = init_sdl(argv[0], SCREEN_WIDTH, SCREEN_HEIGHT, SOUND_SAMPLERATE, sdl_sound_chunk);
313 rc = init_opengl(IMAGE_WIDTH, IMAGE_HEIGHT);
316 resize_opengl(SCREEN_WIDTH, SCREEN_HEIGHT);
318 /* init audio filter */
319 sound_init_filter(SOUND_SAMPLERATE);
324 printf("**********************************\n");
325 printf("* Welcome to Mercenary Reloaded! *\n");
326 printf("**********************************\n\n");
327 printf("Press CTRL + cursor keys to select inventory or pickup/drop item.\n");
328 printf("Press CTRL + f to toggle full screen.\n");
329 printf("Press CTRL + s to toggle rendering speed.\n");
330 printf("Press CTRL + v to toggle video filter.\n");
331 printf("Press CTRL + a to toggle audio filter.\n");
332 printf("Press CTRL + c to exit game.\n\n");
333 printf("Use '--help' as command line option for configuration settings.\n\n");
354 void audio_sdl(float *data, int length)
358 /* read sound from sound buffer
359 * buffer pointer read and write is atomic, so no locking required!
361 fill = (sound_buffer_writep - sound_buffer_readp + sound_buffer_size) % sound_buffer_size;
363 #ifdef DEBUG_SOUND_BUFFERING
364 fprintf(stderr, "sound buffer underrun\n");
366 /* correct read pointer as if the buffer would have 'length' of samples stored inside */
367 sound_buffer_readp = (sound_buffer_readp + fill - length + sound_buffer_size) % sound_buffer_size;
369 for (s = 0; s < length; s++)
370 *data++ = sound_buffer[(sound_buffer_readp + s) % sound_buffer_size];
371 #ifdef DEBUG_SOUND_BUFFERING
372 printf("fill %d = %.4f\n", length, sound_buffer[sound_buffer_readp]);
374 sound_buffer_readp =(sound_buffer_readp + length) % sound_buffer_size;
377 static int shift = 0, ctrl = 0;
379 void keyboard_sdl(int down, SDL_Keycode sym)
388 config_video_filter ^= 1;
389 printf("video filter: %s\n", (config_video_filter) ? "on" : "off");
394 config_audio_filter ^= 1;
395 printf("audio filter: %s\n", (config_audio_filter) ? "on" : "off");
400 config_amiga_speed ^= 1;
401 printf("amiga speed: %s\n", (config_amiga_speed) ? "original" : "full");
412 set_key("LSH", down);
416 set_key("RSH", down);
422 set_joystick(-1, -1, -1, -1, -1);
426 set_joystick(down, -1, -1, -1, -1);
431 set_joystick(-1, -1, -1, -1, -1);
435 set_joystick(-1, down, -1, -1, -1);
440 set_joystick(-1, -1, -1, -1, -1);
444 set_joystick(-1, -1, down, -1, -1);
449 set_joystick(-1, -1, -1, -1, -1);
453 set_joystick(-1, -1, -1, down, -1);
456 set_joystick(-1, -1, -1, -1, down);
459 case SDLK_a: set_key("A", down); break;
460 case SDLK_b: set_key("B", down); break;
461 case SDLK_c: set_key("C", down); break;
462 case SDLK_d: set_key("D", down); break;
463 case SDLK_e: set_key("E", down); break;
464 case SDLK_f: set_key("F", down); break;
465 case SDLK_g: set_key("G", down); break;
466 case SDLK_h: set_key("H", down); break;
467 case SDLK_i: set_key("I", down); break;
468 case SDLK_j: set_key("J", down); break;
469 case SDLK_k: set_key("K", down); break;
470 case SDLK_l: set_key("L", down); break;
471 case SDLK_m: set_key("M", down); break;
472 case SDLK_n: set_key("N", down); break;
473 case SDLK_o: set_key("O", down); break;
474 case SDLK_p: set_key("P", down); break;
475 case SDLK_q: set_key("Q", down); break;
476 case SDLK_r: set_key("R", down); break;
477 case SDLK_s: set_key("S", down); break;
478 case SDLK_t: set_key("T", down); break;
479 case SDLK_u: set_key("U", down); break;
480 case SDLK_v: set_key("V", down); break;
481 case SDLK_w: set_key("W", down); break;
482 case SDLK_x: set_key("X", down); break;
483 case SDLK_y: set_key("Y", down); break;
484 case SDLK_z: set_key("Z", down); break;
486 case SDLK_0: set_key("0", down); break;
487 case SDLK_1: set_key("1", down); break;
488 case SDLK_2: set_key("2", down); break;
489 case SDLK_3: set_key("3", down); break;
490 case SDLK_4: set_key("4", down); break;
491 case SDLK_5: set_key("5", down); break;
492 case SDLK_6: set_key("6", down); break;
493 case SDLK_7: set_key("7", down); break;
494 case SDLK_8: set_key("8", down); break;
495 case SDLK_9: set_key("9", down); break;
497 case SDLK_KP_0: set_key("NP0", down); break;
498 case SDLK_KP_1: set_key("NP1", down); break;
499 case SDLK_KP_2: set_key("NP2", down); break;
500 case SDLK_KP_3: set_key("NP3", down); break;
501 case SDLK_KP_4: set_key("NP4", down); break;
502 case SDLK_KP_5: set_key("NP5", down); break;
503 case SDLK_KP_6: set_key("NP6", down); break;
504 case SDLK_KP_7: set_key("NP7", down); break;
505 case SDLK_KP_8: set_key("NP8", down); break;
506 case SDLK_KP_9: set_key("NP9", down); break;
507 case SDLK_KP_DIVIDE: set_key("NPDIV", down); break;
508 case SDLK_KP_MULTIPLY: set_key("NPMUL", down); break;
509 case SDLK_KP_MINUS: set_key("NPSUB", down); break;
510 case SDLK_KP_PLUS: set_key("NPADD", down); break;
511 case SDLK_KP_PERIOD: set_key("NPDEL", down); break;
512 // NPLPAREN and NPRPAREN are not emulated
514 case SDLK_F1: set_key("F1", down); break;
515 case SDLK_F2: set_key("F2", down); break;
516 case SDLK_F3: set_key("F3", down); break;
517 case SDLK_F4: set_key("F4", down); break;
518 case SDLK_F5: set_key("F5", down); break;
519 case SDLK_F6: set_key("F6", down); break;
520 case SDLK_F7: set_key("F7", down); break;
521 case SDLK_F8: set_key("F8", down); break;
522 case SDLK_F9: set_key("F9", down); break;
523 case SDLK_F10: set_key("F10", down); break;
525 case SDLK_SPACE: set_key("SPC", down); break;
526 case SDLK_BACKSPACE: set_key("BS", down); break;
527 case SDLK_TAB: set_key("TAB", down); break;
528 case SDLK_KP_ENTER: set_key("ENT", down); break;
529 case SDLK_RETURN: set_key("RET", down); break;
530 case SDLK_ESCAPE: set_key("ESC", down); break;
531 case SDLK_DELETE: set_key("DEL", down); break;
532 case SDLK_INSERT: set_key("HELP", down); break;
537 uint16_t emulate_io_read(uint32_t address)
539 uint16_t value = 0xffff;
541 /* joystick and fire button */
542 if (address == 0xbfe000 || address == 0xdff00c)
543 value &= emulate_joystick_read(address);
545 if (address == 0xbfec00 || address == 0xbfed00 || address == 0xbfee00)
546 value &= emulate_keyboard_read(address);
548 if (address == 0xbfd100 || address == 0xbfe000 || address == 0xdff01a || address == 0xdff01e)
549 value &= emulate_disk_read(address);
554 void emulate_io_write(uint32_t address, uint16_t value)
556 /* dmacon and sound registers */
557 if (address == 0xdff096 || (address >= 0xdff0a0 && address <= 0xdff0df))
558 emulate_sound_write(address, value, SOUND_SAMPLERATE);
559 if (address == 0xbfd100 || (address >= 0xdff020 && address <= 0xdff024))
560 emulate_disk_write(address, value);
563 /* two tracks with 0x1820 words of length */
564 static uint8_t game_save[2][0x1820 << 1];
565 static int last_track = 0;
567 /* game reads track with saved game */
568 void disk_read(int track, int __attribute__((unused)) side, uint32_t data, uint16_t length)
570 if (length > sizeof(game_save[0])) {
571 fprintf(stderr, "loading game state failed, because length exceeds game save data size, please fix!\n");
575 /* if even track is selected, load game */
578 int gamesave_num = (track - 2) >> 1;
582 memset(game_save, 0, sizeof(game_save)); /* clear so make the game fail, if we fail */
583 sprintf(filename, "%s/%s/%d.gamesave", home_dir, config_gamesave_dir, gamesave_num);
584 fp = fopen(filename, "r");
587 fprintf(stderr, "failed to load game from '%s'\n", filename);
590 got = fread(game_save, sizeof(game_save[0]), 2, fp);
598 memcpy(memory + data, game_save[track & 1], length /* sizeof(game_save[0])*/);
601 /* game writes track with saved game */
602 void disk_write(int track, int __attribute__((unused)) side, uint32_t data, uint16_t length)
604 /* skip sync info that is provided by game and only relevant for a real disk track */
608 if (length != sizeof(game_save[0])) {
609 fprintf(stderr, "saving game state failed, because length of data does not match, please fix!\n");
613 /* don't save if last track is the same, because disk is written on both sides with the same data */
614 if (track == last_track) {
615 if (memcmp(memory + data, game_save[track & 1], length)) {
616 fprintf(stderr, "saving game data on other side of the disk is different, please fix!\n");
623 memcpy(game_save[track & 1], memory + data, length);
625 /* if done with saving */
628 int gamesave_num = (track - 2) >> 1;
632 sprintf(filename, "%s/%s", home_dir, config_gamesave_dir);
633 mkdir(filename, 0777);
634 sprintf(filename + strlen(filename), "/%d.gamesave", gamesave_num);
635 fp = fopen(filename, "w");
638 fprintf(stderr, "failed to save game to '%s'\n", filename);
641 printf("Game state saved to '%s'\n", filename);
642 wrote = fwrite(game_save, sizeof(game_save[0]), 2, fp);