add arrow support to 2048

Reviewed-on: #29

src/engine/engine.c

@@ -2,6 +2,8 @@
 
 #include "internal/engine_internal.h"
 
+#include <stdlib.h>
+
 engine_internal_state_t *internal_state = NULL;
 game_state_t *game_state = NULL;
 

src/examples/2048.c

@@ -28,6 +28,14 @@ typedef struct {
     int col;
 } line_tile_t;
 
+typedef enum {
+    GAME_PLAYING,
+    GAME_WON,
+    GAME_LOST
+} game_status_t;
+
+static game_status_t game_status;
+
 typedef struct {
     uint32_t area[SIZE][SIZE];
     dir_e direction;
@@ -42,6 +50,17 @@ static size_t move_track_count;
 
 static double last_frame_time;
 
+static bool
+board_is_full(void)
+{
+    for (int r = 0; r < SIZE; ++r)
+        for (int c = 0; c < SIZE; ++c)
+            if (game.area[r][c] == 0)
+                return false;
+
+    return true;
+}
+
 /* Pixel size is calculated from the current window size while drawing. */
 static uint32_t
 colors(uint32_t number)
@@ -151,6 +170,8 @@ process_line(dir_e direction, int line, uint32_t output[SIZE])
         if (i + 1 < input_count &&
             input[i].value == input[i + 1].value) {
             uint32_t merged_value = input[i].value * 2;
+            if (merged_value >= 2048)
+                game_status = GAME_WON;
 
             output[output_count] = merged_value;
             game.score += merged_value;
@@ -194,6 +215,9 @@ process_line(dir_e direction, int line, uint32_t output[SIZE])
 static bool
 slide(dir_e direction)
 {
+    if (game_status != GAME_PLAYING || anim_is_active(&movement))
+        return false;
+
     if (anim_is_active(&movement))
         return false;
 
@@ -260,16 +284,24 @@ client_poll_event(void)
         game_state->is_running = false;
         break;
     case SDLK_W:
-        slide(UP);
+    case SDLK_UP:
+        if (game_status == GAME_PLAYING)
+           slide(UP);
         break;
     case SDLK_S:
-        slide(DOWN);
+    case SDLK_DOWN:
+        if (game_status == GAME_PLAYING)
+            slide(DOWN);
         break;
     case SDLK_A:
-        slide(LEFT);
+    case SDLK_LEFT:
+        if (game_status == GAME_PLAYING)
+            slide(LEFT);
         break;
     case SDLK_D:
-        slide(RIGHT);
+    case SDLK_RIGHT:
+        if (game_status == GAME_PLAYING)
+            slide(RIGHT);
         break;
     default:
         break;
@@ -324,7 +356,12 @@ client_update_framebuffer(void)
         dt = 0.05f;
 
     if (anim_is_active(&movement) && anim_update(&movement, dt)) {
-        new_2();
+        if (game_status == GAME_PLAYING) {
+            new_2();
+
+            if (board_is_full())
+                game_status = GAME_LOST;
+        }
     }
 
     uint32_t tile_size = game_state->width / SIZE;
@@ -332,7 +369,26 @@ client_update_framebuffer(void)
 
     clear_framebuffer(OVERDRAW, 0x000000);
 
-    /* Draw all cell backgrounds first. */
+    char score_text[32];
+    snprintf(score_text, sizeof score_text, "score: %u", game.score);
+    put_string(OVERDRAW, score_text,
+               border_width / 2, tile_size * SIZE + border_width / 2,
+               6, 1, 12, 0xFFFFFF, 0x000000);
+    
+    if (game_status != GAME_PLAYING) {
+        clear_framebuffer(BASE, 0x000000);
+        const char *message =
+            game_status == GAME_WON ? "YOU WIN!" : "YOU LOSE!";
+
+        put_string(OVERDRAW, message,
+                   0 + border_width * 2,
+                   game_state->height / 2,
+                   6, 1, 12, 0xFFFFFF, 0x000000);
+
+        return;
+    }
+
+    /* Draw all cell backgrounds. */
     for (int r = 0; r < SIZE; ++r) {
         for (int c = 0; c < SIZE; ++c) {
             uint32_t x = border_width / 2 + (uint32_t)c * tile_size;
@@ -360,17 +416,12 @@ client_update_framebuffer(void)
             }
         }
     }
-
-    char score_text[32];
-    snprintf(score_text, sizeof score_text, "score: %u", game.score);
-    put_string(OVERDRAW, score_text,
-               border_width / 2, tile_size * SIZE + border_width / 2,
-               6, 1, 12, 0xFFFFFF, 0x000000);
 }
 
 static void
 game_init(void)
 {
+    game_status = GAME_PLAYING;
     memset(&game, 0, sizeof game);
     anim_init(&movement);
     srand((unsigned)time(NULL));