path: root/reverse-engineering/dosbox_snif/dos_lemm_sim.c

#include "dos_lemm_sim.h"
#include "utils.h" /* imin() */

uint8_t is_solid(uint16_t x, uint16_t y);

// Code segment 0x0208, offsets in comments
void move_lemmings(struct game_data *g) {
	uint8_t *g_raw = (uint8_t *) g;
	struct _lemm_data *lemm;
	uint8_t *lemm_raw;
	uint16_t y_test=0x55AA; //=21930 remarkable value if we hit a bug
	int i;

	//182F
	if ( g->paused ) {
		g_raw[0x4d] = FALSE;
		return;
	}
	//1839
	//TODO vga_set_read_mode1_compare_plan3_to_color_8();

	//183C
	g_raw[0x4d] = TRUE;

	//1841
	lemm=&(g->lemmings[0]);
	lemm_raw = (uint8_t *) lemm; // Instrumentation
	// Replaced (instrumentation)
	//g->lemm_count_to_process = g->lemm_spawned_count;
	g->lemm_count_to_process = imin(g->lemm_spawned_count, (sizeof(g->lemmings) / sizeof(struct _lemm_data)));

	//184A
	while ( g->lemm_count_to_process != 0 ) {
		//XXX push es
		//1852
		if ( lemm->is_gone ) {
			goto next_lemming;
		}
		//185B
		if ( lemm->expl_countdown != 0 ) {
			//TODO if ( commit_suicide() != FALSE ) goto next_lemming;
		}
		//186A
		if ( lemm->flags1.bits.walk_pause_for_shruggling ) {
			goto lbl_anim_but_no_move;
		}
		//1877
		if ( lemm->state.raw == 0x0 )		goto lbl_walking;
		if ( lemm->state.bits.s_exploding_spe )	goto lbl_exploding_spe;
		if ( lemm->state.bits.s_exploding )	goto lbl_exploding;
		if ( lemm->state.bits.s_falling )	goto lbl_falling;
		if ( lemm->state.bits.s_floating )	goto lbl_floating;
		if ( lemm->state.bits.s_splatting )	goto lbl_splatting;
		if ( lemm->state.bits.s_ascending )	goto lbl_ascending;
		if ( lemm->state.bits.s_digging )	goto lbl_digging;
		if ( lemm->state.bits.s_climbing )	goto lbl_climbing;
		if ( lemm->state.bits.s_climb_ending )	goto lbl_climb_ending;
		if ( lemm->state.bits.s_building )	goto lbl_building;
		if ( lemm->state.bits.s_blocking )	goto lbl_blocking;
		if ( lemm->state.bits.s_bashing )	goto lbl_bashing;
		if ( lemm->state.bits.s_mining )	goto lbl_mining;
		if ( lemm->state.bits.s_drawning )	goto lbl_drawning;
		if ( lemm->state.bits.s_ending )	goto lbl_ending;
		if ( lemm->state.bits.s_dying )		goto lbl_dying;

check_this_and_go_next_lemming: //18FE
	//TODO process_if_in_special_zone();
next_lemming:	//1901
		//XXX pop es
		lemm++;
		g->lemm_count_to_process--;
		//1909
		if ( g->lemm_count_to_process != 0 ) continue;
		//190E
		if ( g->nuke_all_in_progress ) {
			goto nuke_one_by_one;
		}
	} //1913 end while

	g_raw[0x4d] = FALSE;
	//191A
	return; // General case end point

nuke_one_by_one:	//191B
	if ( g->nuke_i == g->lemm_spawned_count ) {
		//1952
		g->nuke_all_in_progress = 0;
		g_raw[0x4d] = FALSE;
		return;
	}
	//1924
	lemm=&(g->lemmings[g->nuke_i]);
	//1930
	if ( lemm->expl_countdown == 0 ) {
		//1936
		if ( lemm->is_gone ) {
			//193C
			g->nuke_i++;
			goto nuke_one_by_one;
		}
		//1942
		if ( ( lemm->state.raw & (s_exploding | s_splatting | s_exploding_spe) ) == 0 ) {
			lemm->expl_countdown = 79;
		}
	}
	//194D
	g->nuke_i++;
	return;

lbl_walking:	//195D
	lemm->spr_frame = (lemm->spr_frame + 1) % 8;
	lemm->x_effective += lemm->direction;
	//196D
	if ( lemm->x_effective<16 || lemm->x_effective>=LEVEL_WIDTH ) {
		//1A5B
		lemm->direction = - lemm->direction;
		goto check_this_and_go_next_lemming;
	}
	//197E
	//TODO vga_mem_read_prepare_registers();
	y_test = lemm->y_effective;
	lemm->y_effective--;//XXX rustine

	if ( ! is_solid(lemm->x_effective, y_test) ) {
		//19FF
		for (i=0;i<3;i++) {
			if ( ! is_solid(lemm->x_effective, y_test) ) {
				goto walker_adjust_y_or_U_turn;
			}
			y_test--;
		}
		//1A26
		for (i=0;i<3;i++) {
			if ( ! is_solid(lemm->x_effective, y_test) ) {
				//1A82
				//walker_become_ascender
				lemm->state.bits.s_ascending=1;
				lemm->spr_frame = 8;
				y_test = lemm->y_effective - 2;
				goto walker_adjust_y_or_U_turn;
			}
			y_test--;
		}
		//1A55
		//XXX Seems opposite cond in disassembly
		if ( lemm->flags1.bits.cap_climber ) {
			//1A92
			//walker_become_climber
			lemm_raw[0x28]=0;
			lemm_raw[0xa]=0;
			lemm_raw[0xb]=0;
			lemm_raw[0xc]=0;
			lemm_raw[0xd]=0;
			lemm->state.bits.s_climbing = 1;
			lemm_raw[0x10]=0x48;
			lemm_raw[0x11]=0x00;
			lemm_raw[0x12]=0x30;
			lemm_raw[0x13]=0x00;
			lemm->x_spr_offset=-8;
			lemm->y_spr_offset=-12;
			lemm_raw[0x14]=g_raw[0x2d];
			lemm_raw[0x15]=g_raw[0x2e];
			lemm->draw_trick1 = TRUE;
			lemm->draw_hint = 8;
		} else {
			//1A5B
			lemm->direction = - lemm->direction;
		}
		goto check_this_and_go_next_lemming;
	}
	//198B
	for (i=0; i<3; i++) {
		lemm->y_effective++;
		if ( is_solid(lemm->x_effective, lemm->y_effective) ) {
			goto walker_check_fall_out_of_screen;
		}
	}
//walker_become_faller:	//19AF
	lemm->y_effective++;
	lemm->state.bits.s_falling=1;
	lemm_raw[0xa]=0;
	lemm->spr_data_ptr = 0xa42;
	lemm_raw[0x10]=0x5a;
	lemm_raw[0x11]=0x00;
	lemm_raw[0x12]=0x3c;
	lemm_raw[0x13]=0x00;
	lemm->spr_frame = 0;
	lemm->falldist = 3;
	lemm->x_spr_offset = -8;
	lemm->y_spr_offset = -10;
	lemm->draw_hint = hint_falling;
	//19DE
	lemm->ptr2 = g_raw[0x2b];
	lemm->draw_trick1 = FALSE;
	lemm->flags1.bits.walk_pause_for_shruggling = 0;
walker_check_fall_out_of_screen:	//19EC
	y_test = lemm->y_effective;
	if ( y_test >= 180 /* LEVEL_HEIGHT + 20 */ ) {
		lemm->is_gone=TRUE;
		goto next_lemming;
	}
	//19F5
	goto check_this_and_go_next_lemming;


walker_adjust_y_or_U_turn:	//1A61
	lemm->y_effective = y_test;
	if ( y_test + lemm->y_spr_offset <= 10 ) {
		//1A6F
		lemm->y_effective = 9 - lemm->y_spr_offset;
		lemm->direction = -lemm->direction;
		lemm->state.bits.s_ascending=0;
	}
	//1A7F
	goto check_this_and_go_next_lemming;

lbl_falling:
	//1AC9
	lemm->spr_frame = (lemm->spr_frame + 1) % 4;
	if ( lemm->falldist >= 16 && lemm->cap_floater ) {
		//1ADF
		lemm->state.raw = s_floating;
		lemm_raw[0xa]=0;
		lemm_raw[0xc]=0x0b;
		lemm_raw[0xd]=0xaa;
		lemm_raw[0x10]=0x80;
		lemm_raw[0x11]=0x00;
		lemm_raw[0x12]=0x60;
		lemm_raw[0x13]=0x00;
		lemm->spr_frame = 0;
		lemm->floattime_dble = 0;
		lemm->y_spr_offset = -16;
		lemm->draw_hint = hint_special1;
		//1B0A
		lemm->ptr2 = g_raw[0x37];
		lemm->draw_trick1 = TRUE;
		lemm->flags1.bits.walk_pause_for_shruggling = 0;
		goto check_this_and_go_next_lemming;
	}
	//1B1B
	//TODO vga_mem_read_prepare_registers();
	//TODO
	goto check_this_and_go_next_lemming;
lbl_splatting:
	//TODO
	goto next_lemming;
lbl_drawning:
	//TODO
	goto next_lemming;
lbl_ending:
	//TODO
	goto next_lemming;
lbl_dying:
	//TODO
	goto next_lemming;
lbl_exploding_spe:
	//TODO
	goto next_lemming;
lbl_ascending:
	//TODO
	goto walker_adjust_y_or_U_turn;
lbl_digging:
	//TODO
	goto check_this_and_go_next_lemming;
lbl_climbing:
	//TODO
	goto walker_adjust_y_or_U_turn;
lbl_climb_ending:
	//TODO
	goto next_lemming;
lbl_building:
	//TODO
	goto check_this_and_go_next_lemming;
lbl_blocking:
	//TODO
	goto next_lemming;
lbl_bashing:
	//TODO
	goto check_this_and_go_next_lemming;
lbl_floating:
	//TODO
	goto check_this_and_go_next_lemming;
lbl_mining:
	//TODO
	goto check_this_and_go_next_lemming;
lbl_exploding:
	//TODO
	goto next_lemming;
lbl_anim_but_no_move:
	//TODO
	goto check_this_and_go_next_lemming;

} // 26F5 end move_lemmings()




uint8_t is_solid(uint16_t x, uint16_t y) {
	//FIXME : memdump the video memory once at start
	return TRUE;
}

void spawn_lemming(struct game_data *g) {
	// 0208:299A
	//TODO ecrit à l'intuitive, cf disassembly
	g->next_spawn_ticks = ( g->next_spawn_ticks - 1) % g->spawn_rate_ticks;
	return;
}

void draw_lemmings(struct game_data *g) {
	// 0208:2F23
	//TODO très incomplet
	((uint8_t *) g)[0x4d] = FALSE;
}

void fixups_before(struct game_data *g) {
	((uint8_t *) g)[0x4f]++;
}

void fixups_after(struct game_data *g) {
	((uint8_t *) g)[0x53] += 0x10;
	if ( ((uint8_t *) g)[0x53] == 0xD0 ) {
		((uint8_t *) g)[0x53] = 0;
	}
	//0F4F
	if ( ! g->paused ) {
		((uint8_t *) g)[0x82]--;
		if ( ((uint8_t *) g)[0x82] == 0 ) {
			((uint8_t *) g)[0x82] = ((uint8_t *) g)[0x83];
		}
	}
}

void main_loop_ingame(struct game_data *g) {
	//TODO
	fixups_before(g);

	move_lemmings(g);
	draw_lemmings(g);
	spawn_lemming(g);

	fixups_after(g);
}