Implement Conway's Game of Life

cfg/checks/games.mk

@@ -1,5 +1,5 @@
 # Variables for game support
 GAMES_CFLAGS = -DGAMES
-GAMES_OBJ = game_base.o game_centipede.o game_chess.o game_util.o game_snake.o
+GAMES_OBJ = game_base.o game_centipede.o game_chess.o game_life.o game_util.o game_snake.o
 CFLAGS += $(GAMES_CFLAGS)
 OBJ += $(GAMES_OBJ)

src/game_base.c

@@ -29,6 +29,7 @@
 #include "game_centipede.h"
 #include "game_base.h"
 #include "game_chess.h"
+#include "game_life.h"
 #include "game_snake.h"
 #include "line_info.h"
 #include "misc_tools.h"
@@ -77,6 +78,7 @@ struct GameList {
 static struct GameList game_list[] = {
     { "centipede", GT_Centipede  },
     { "chess",     GT_Chess      },
+    { "life",      GT_Life       },
     { "snake",     GT_Snake      },
     {  NULL,       GT_Invalid    },
 };
@@ -213,6 +215,11 @@ static int game_initialize_type(GameData *game, const uint8_t *data, size_t leng
             break;
         }
 
+        case GT_Life: {
+            ret = life_initialize(game);
+            break;
+        }
+
         default: {
             break;
         }
@@ -980,6 +987,11 @@ void game_update_score(GameData *game, long int points)
     }
 }
 
+void game_set_score(GameData *game, long int val)
+{
+    game->score = val;
+}
+
 long int game_get_score(const GameData *game)
 {
     return game->score;

src/game_base.h

@@ -56,7 +56,7 @@
 #define GAME_MESSAGE_DEFAULT_TIMEOUT 3
 
 
-/***** NETWORKING DEFINES *****/
+/***** NETWORKING CONSTANTS *****/
 
 /* Header starts after custom packet type byte. Comprised of: NetworkVersion (1b) + GameType (1b) + id (4b) */
 #define GAME_PACKET_HEADER_SIZE (1 + 1 + sizeof(uint32_t))
@@ -99,6 +99,7 @@ typedef enum GameStatus {
 typedef enum GameType {
     GT_Centipede = 0u,
     GT_Chess,
+    GT_Life,
     GT_Snake,
     GT_Invalid,
 } GameType;
@@ -297,6 +298,11 @@ void game_window_notify(const GameData *game, const char *message);
  */
 void game_update_score(GameData *game, long int points);
 
+/*
+ * Sets game score to `val`.
+ */
+void game_set_score(GameData *game, long int score);
+
 /*
  * Returns the game's current score.
  */

src/game_centipede.c

@@ -1593,6 +1593,7 @@ void cent_cb_kill(GameData *game, void *cb_data)
     game_set_cb_update_state(game, NULL, NULL);
     game_set_cb_render_window(game, NULL, NULL);
     game_set_cb_kill(game, NULL, NULL);
+    game_set_cb_on_keypress(game, NULL, NULL);
     game_set_cb_on_pause(game, NULL, NULL);
 }
 

src/game_chess.c

@@ -1411,7 +1411,7 @@ static void chess_move_curs_left(ChessState *state)
 {
     Board *board = &state->board;
 
-    size_t new_x = state->curs_x - CHESS_TILE_SIZE_X;
+    int new_x = state->curs_x - CHESS_TILE_SIZE_X;
 
     if (new_x < board->x_left_bound) {
         return;
@@ -1424,7 +1424,7 @@ static void chess_move_curs_right(ChessState *state)
 {
     Board *board = &state->board;
 
-    size_t new_x = state->curs_x + CHESS_TILE_SIZE_X;
+    int new_x = state->curs_x + CHESS_TILE_SIZE_X;
 
     if (new_x > board->x_right_bound) {
         return;
@@ -1437,7 +1437,7 @@ static void chess_move_curs_up(ChessState *state)
 {
     Board *board = &state->board;
 
-    size_t new_y = state->curs_y - CHESS_TILE_SIZE_Y;
+    int new_y = state->curs_y - CHESS_TILE_SIZE_Y;
 
     if (new_y < board->y_top_bound) {
         return;
@@ -1450,7 +1450,7 @@ static void chess_move_curs_down(ChessState *state)
 {
     Board *board = &state->board;
 
-    size_t new_y = state->curs_y + CHESS_TILE_SIZE_Y;
+    int new_y = state->curs_y + CHESS_TILE_SIZE_Y;
 
     if (new_y >= board->y_bottom_bound) {
         return;
@@ -1716,7 +1716,6 @@ void chess_cb_render_window(GameData *game, WINDOW *win, void *cb_data)
 
     move(state->curs_y, state->curs_x);
 
-
     curs_set(1);
 
     chess_draw_board(win, state);

src/game_life.c

@@ -0,0 +1,602 @@
+/*  game_life.c
+ *
+ *
+ *  Copyright (C) 2021 Toxic All Rights Reserved.
+ *
+ *  This file is part of Toxic.
+ *
+ *  Toxic is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  Toxic is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with Toxic.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "game_life.h"
+
+#define LIFE_DEFAULT_CELL_CHAR     'o'
+#define LIFE_CELL_DEFAULT_COLOUR    CYAN
+#define LIFE_DEFAULT_SPEED          25
+#define LIFE_MAX_SPEED              40
+
+/* Determines the additional size of the grid beyond the visible boundaries.
+ *
+ * This buffer allows cells to continue growing off-screen giving the illusion of an
+ * infinite grid to a certain point.
+ */
+#define LIFE_BOUNDARY_BUFFER        50
+
+
+typedef struct Cell {
+    Coords     coords;
+    bool       alive;
+    bool       marked;  // true if cell should invert alive status at end of current cycle
+    int        display_char;
+    size_t     age;
+} Cell;
+
+typedef struct LifeState {
+    TIME_MS    time_last_cycle;
+    size_t     speed;
+    size_t     generation;
+
+    Cell       **cells;
+    int        num_columns;
+    int        num_rows;
+
+    int        curs_x;
+    int        curs_y;
+
+    int        x_left_bound;
+    int        x_right_bound;
+    int        y_top_bound;
+    int        y_bottom_bound;
+
+    short      display_candy;
+} LifeState;
+
+
+static void life_increase_speed(LifeState *state)
+{
+    if (state->speed < LIFE_MAX_SPEED) {
+        ++state->speed;
+    }
+}
+
+static void life_decrease_speed(LifeState *state)
+{
+    if (state->speed > 1) {
+        --state->speed;
+    }
+}
+
+static int life_get_display_char(const LifeState *state, const Cell *cell)
+{
+    if (state->display_candy == 1) {
+        if (cell->age == 1) {
+            return '.';
+        }
+
+        return '+';
+    }
+
+    if (state->display_candy == 2) {
+        if (cell->age == 1) {
+            return '.';
+        }
+
+        if (cell->age == 2) {
+            return '-';
+        }
+
+        if (cell->age == 3) {
+            return 'o';
+        }
+
+        return 'O';
+    }
+
+    return 'o';
+}
+
+static void life_toggle_display_candy(LifeState *state)
+{
+    state->display_candy = (state->display_candy + 1) % 3;  // magic number depends on life_get_display_char()
+}
+
+static Cell *life_get_cell_at_coords(const LifeState *state, const int x, const int y)
+{
+    const int i = y - (state->y_top_bound - (LIFE_BOUNDARY_BUFFER / 2));
+    const int j = x - (state->x_left_bound - (LIFE_BOUNDARY_BUFFER / 2));
+
+    if (i >= 0 && j >= 0) {
+        return &state->cells[i][j];
+    }
+
+    return NULL;
+}
+
+static void life_draw_cells(const GameData *game, WINDOW *win, LifeState *state)
+{
+    for (int i = LIFE_BOUNDARY_BUFFER / 2; i < state->num_rows - (LIFE_BOUNDARY_BUFFER / 2); ++i) {
+        for (int j = LIFE_BOUNDARY_BUFFER / 2; j < state->num_columns + 1 - (LIFE_BOUNDARY_BUFFER / 2); ++j) {
+            Cell *cell = &state->cells[i][j];
+
+            if (cell->alive) {
+                Coords coords = cell->coords;
+                wattron(win, A_BOLD | COLOR_PAIR(LIFE_CELL_DEFAULT_COLOUR));
+                mvwaddch(win, coords.y, coords.x, cell->display_char);
+                wattroff(win, A_BOLD | COLOR_PAIR(LIFE_CELL_DEFAULT_COLOUR));
+            }
+        }
+    }
+}
+
+static void life_toggle_cell(LifeState *state)
+{
+    Cell *cell = life_get_cell_at_coords(state, state->curs_x, state->curs_y);
+
+    if (cell == NULL) {
+        return;
+    }
+
+    cell->alive ^= 1;
+}
+
+/*
+ * Returns the number of live neighbours of `idx` cell.
+ */
+static int life_get_live_neighbours(const LifeState *state, const int i, const int j)
+{
+    Cell *n[8] = {0};
+
+    if (i > 0 && j > 0) {
+        n[0] = &state->cells[i - 1][j - 1];
+    }
+
+    if (i > 0) {
+        n[1] = &state->cells[i - 1][j];
+    }
+
+    if (i > 0 && j < state->num_columns - 1) {
+        n[2] = &state->cells[i - 1][j + 1];
+    }
+
+    if (j > 0) {
+        n[3] = &state->cells[i][j - 1];
+    }
+
+    if (j < state->num_columns - 1) {
+        n[4] = &state->cells[i][j + 1];
+    }
+
+    if (i < state->num_rows - 1 && j > 0) {
+        n[5] = &state->cells[i + 1][j - 1];
+    }
+
+    if (i < state->num_rows - 1) {
+        n[6] = &state->cells[i + 1][j];
+    }
+
+    if (i < state->num_rows - 1 && j < state->num_columns - 1) {
+        n[7] = &state->cells[i + 1][j + 1];
+    }
+
+    int count = 0;
+
+    for (size_t i = 0; i < 8; ++i) {
+        if (n[i] == NULL) {
+            return 0; // If we're at a boundary kill cell
+        }
+
+        if (n[i]->alive) {
+            ++count;
+        }
+    }
+
+    return count;
+}
+
+static void life_restart(GameData *game, LifeState *state)
+{
+    for (int i = 0; i < state->num_rows; ++i) {
+        for (int j = 0; j < state->num_columns; ++j) {
+            Cell *cell = &state->cells[i][j];
+            cell->alive = false;
+            cell->marked = false;
+            cell->display_char = LIFE_DEFAULT_CELL_CHAR;
+            cell->age = 0;
+        }
+    }
+
+    game_set_score(game, 0);
+
+    state->generation = 0;
+}
+
+static void life_do_cells(LifeState *state)
+{
+
+    for (int i = 0; i < state->num_rows; ++i) {
+        for (int j = 0; j < state->num_columns; ++j) {
+            Cell *cell = &state->cells[i][j];
+
+            if (cell->marked) {
+                cell->marked = false;
+                cell->alive ^= 1;
+                cell->age = cell->alive;
+                cell->display_char = life_get_display_char(state, cell);
+            } else if (cell->alive) {
+                ++cell->age;
+                cell->display_char = life_get_display_char(state, cell);
+            }
+        }
+    }
+}
+
+static void life_cycle(GameData *game, LifeState *state)
+{
+    if (state->generation == 0) {
+        return;
+    }
+
+    TIME_MS cur_time = get_time_millis();
+
+    if (!game_do_object_state_update(game, cur_time, state->time_last_cycle, state->speed)) {
+        return;
+    }
+
+    state->time_last_cycle = get_time_millis();
+
+    ++state->generation;
+
+    size_t live_cells = 0;
+
+    for (int i = 0; i < state->num_rows; ++i) {
+        for (int j = 0; j < state->num_columns; ++j) {
+            Cell *cell = &state->cells[i][j];
+
+            int live_neighbours = life_get_live_neighbours(state, i, j);
+
+            if (cell->alive) {
+                if (!(live_neighbours == 2 || live_neighbours == 3)) {
+                    cell->marked = true;
+                } else {
+                    ++live_cells;
+                }
+            } else {
+                if (live_neighbours == 3) {
+                    cell->marked = true;
+                    ++live_cells;
+                }
+            }
+        }
+    }
+
+    if (live_cells == 0) {
+        life_restart(game, state);
+        return;
+    }
+
+    life_do_cells(state);
+
+    game_update_score(game, 1);
+}
+
+static void life_start(GameData *game, LifeState *state)
+{
+    state->generation = 1;
+}
+
+void life_cb_update_game_state(GameData *game, void *cb_data)
+{
+    if (!cb_data) {
+        return;
+    }
+
+    LifeState *state = (LifeState *)cb_data;
+
+    life_cycle(game, state);
+}
+
+void life_cb_render_window(GameData *game, WINDOW *win, void *cb_data)
+{
+    if (!cb_data) {
+        return;
+    }
+
+    LifeState *state = (LifeState *)cb_data;
+
+    move(state->curs_y, state->curs_x);
+
+    curs_set(1);
+
+    life_draw_cells(game, win, state);
+}
+
+static void life_move_curs_left(LifeState *state)
+{
+    int new_x = state->curs_x - 1;
+
+    if (new_x < state->x_left_bound) {
+        return;
+    }
+
+    state->curs_x = new_x;
+}
+
+static void life_move_curs_right(LifeState *state)
+{
+    int new_x = state->curs_x + 1;
+
+    if (new_x > state->x_right_bound) {
+        return;
+    }
+
+    state->curs_x = new_x;
+}
+
+static void life_move_curs_up(LifeState *state)
+{
+    int new_y = state->curs_y - 1;
+
+    if (new_y < state->y_top_bound) {
+        return;
+    }
+
+    state->curs_y = new_y;
+}
+
+static void life_move_curs_down(LifeState *state)
+{
+    int new_y = state->curs_y + 1;
+
+    if (new_y >= state->y_bottom_bound) {
+        return;
+    }
+
+    state->curs_y = new_y;
+}
+
+static void life_move_curs_up_left(LifeState *state)
+{
+    life_move_curs_up(state);
+    life_move_curs_left(state);
+}
+
+static void life_move_curs_up_right(LifeState *state)
+{
+    life_move_curs_up(state);
+    life_move_curs_right(state);
+}
+
+static void life_move_curs_down_right(LifeState *state)
+{
+    life_move_curs_down(state);
+    life_move_curs_right(state);
+}
+
+static void life_move_curs_down_left(LifeState *state)
+{
+    life_move_curs_down(state);
+    life_move_curs_left(state);
+}
+
+void life_cb_on_keypress(GameData *game, int key, void *cb_data)
+{
+    if (!cb_data) {
+        return;
+    }
+
+    LifeState *state = (LifeState *)cb_data;
+
+    switch (key) {
+        case KEY_LEFT: {
+            life_move_curs_left(state);
+            break;
+        }
+
+        case KEY_RIGHT: {
+            life_move_curs_right(state);
+            break;
+        }
+
+        case KEY_DOWN: {
+            life_move_curs_down(state);
+            break;
+        }
+
+        case KEY_UP: {
+            life_move_curs_up(state);
+            break;
+        }
+
+        case KEY_HOME: {
+            life_move_curs_up_left(state);
+            break;
+        }
+
+        case KEY_END: {
+            life_move_curs_down_left(state);
+            break;
+        }
+
+        case KEY_PPAGE: {
+            life_move_curs_up_right(state);
+            break;
+        }
+
+        case KEY_NPAGE: {
+            life_move_curs_down_right(state);
+            break;
+        }
+
+        case '\r': {
+            if (state->generation > 0) {
+                life_restart(game, state);
+            } else {
+                life_start(game, state);
+            }
+
+            break;
+        }
+
+        case ' ': {
+            life_toggle_cell(state);
+            break;
+        }
+
+        case '=':
+
+        /* intentional fallthrough */
+
+        case '+': {
+            life_increase_speed(state);
+            break;
+        }
+
+        case '-':
+
+        /* intentional fallthrough */
+
+        case '_': {
+            life_decrease_speed(state);
+            break;
+        }
+
+        case '\t': {
+            life_toggle_display_candy(state);
+        }
+
+        default: {
+            return;
+        }
+    }
+}
+
+static void life_free_cells(LifeState *state)
+{
+    if (state->cells == NULL) {
+        return;
+    }
+
+    for (int i = 0; i < state->num_rows; ++i) {
+        if (state->cells[i]) {
+            free(state->cells[i]);
+        }
+    }
+
+    free(state->cells);
+}
+
+void life_cb_kill(GameData *game, void *cb_data)
+{
+    if (!cb_data) {
+        return;
+    }
+
+    LifeState *state = (LifeState *)cb_data;
+
+    life_free_cells(state);
+    free(state);
+
+    game_set_cb_update_state(game, NULL, NULL);
+    game_set_cb_render_window(game, NULL, NULL);
+    game_set_cb_kill(game, NULL, NULL);
+    game_set_cb_on_keypress(game, NULL, NULL);
+}
+
+static int life_init_state(GameData *game, LifeState *state)
+{
+    const int x_left = game_x_left_bound(game) ;
+    const int x_right = game_x_right_bound(game);
+    const int y_top = game_y_top_bound(game);
+    const int y_bottom = game_y_bottom_bound(game) + 1;
+
+    state->x_left_bound = x_left;
+    state->x_right_bound = x_right;
+    state->y_top_bound = y_top;
+    state->y_bottom_bound = y_bottom;
+
+    const int x_mid = x_left + ((x_right - x_left) / 2);
+    const int y_mid = y_top + ((y_bottom - y_top) / 2);
+
+    state->curs_x = x_mid;
+    state->curs_y = y_mid;
+
+    const int num_rows = (y_bottom - y_top) + LIFE_BOUNDARY_BUFFER;
+    const int num_columns = (x_right - x_left) + LIFE_BOUNDARY_BUFFER;
+
+    if (num_rows <= 0 || num_columns <= 0) {
+        return -1;
+    }
+
+    state->num_columns = num_columns;
+    state->num_rows = num_rows;
+
+    state->cells = calloc(1, num_rows * sizeof(Cell *));
+
+    if (state->cells == NULL) {
+        return -1;
+    }
+
+    for (int i = 0; i < num_rows; ++i) {
+        state->cells[i] = calloc(1, num_columns * sizeof(Cell));
+
+        if (state->cells[i] == NULL) {
+            return -1;
+        }
+
+        for (int j = 0; j < num_columns; ++j) {
+            state->cells[i][j].coords.y = i + (state->y_top_bound - (LIFE_BOUNDARY_BUFFER / 2));
+            state->cells[i][j].coords.x = j + (state->x_left_bound - (LIFE_BOUNDARY_BUFFER / 2));
+        }
+    }
+
+    state->speed = LIFE_DEFAULT_SPEED;
+
+    life_restart(game, state);
+
+    return 0;
+}
+
+int life_initialize(GameData *game)
+{
+    if (game_set_window_shape(game, GW_ShapeRectangle) == -1) {
+        return -1;
+    }
+
+    LifeState *state = calloc(1, sizeof(LifeState));
+
+    if (state == NULL) {
+        return -1;
+    }
+
+    if (life_init_state(game, state) == -1) {
+        life_free_cells(state);
+        free(state);
+        return -1;
+    }
+
+    game_set_update_interval(game, 40);
+    game_show_score(game, true);
+
+    game_set_cb_update_state(game, life_cb_update_game_state, state);
+    game_set_cb_render_window(game, life_cb_render_window, state);
+    game_set_cb_on_keypress(game, life_cb_on_keypress, state);
+    game_set_cb_kill(game, life_cb_kill, state);
+
+    return 0;
+}

src/game_life.h

@@ -0,0 +1,31 @@
+/*  game_life.h
+ *
+ *
+ *  Copyright (C) 2021 Toxic All Rights Reserved.
+ *
+ *  This file is part of Toxic.
+ *
+ *  Toxic is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  Toxic is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with Toxic.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifndef GAME_LIFE
+#define GAME_LIFE
+
+#include "game_base.h"
+
+int life_initialize(GameData *game);
+
+#endif // GAME_LIFE
+

src/game_snake.c

@@ -801,6 +801,7 @@ void snake_cb_kill(GameData *game, void *cb_data)
     game_set_cb_update_state(game, NULL, NULL);
     game_set_cb_render_window(game, NULL, NULL);
     game_set_cb_kill(game, NULL, NULL);
+    game_set_cb_on_keypress(game, NULL, NULL);
     game_set_cb_on_pause(game, NULL, NULL);
 }