squash

example/snek.c

@@ -0,0 +1,130 @@
+// Simple game of snake to show how to do animation and draw cells.
+
+#include "../tim.h"
+
+#define FG  0x10
+#define BG  0xdd
+#define BTN (FG << 16 | BG << 8 | FG)
+
+#define NEW   0
+#define RUN   1
+#define PAUSE 2
+#define OVER  3
+
+typedef union {
+    struct {
+        int32_t x;
+        int32_t y;
+    };
+    int64_t xy;
+} point;
+
+static struct {
+    int     state;     // game state (NEW RUN PAUSE OVER)
+    int64_t tick;      // updates every 10 ms
+    int     len;       // snake length
+    point   body[200]; // snake body
+    point   food;      // food position
+    point   look;      // active direction
+} snek;
+
+static void start(void) {
+    memset(snek.body, -1, sizeof(snek.body));
+    snek.len     = 2;
+    snek.body[0] = (point){{1, tim.h / 2}};
+    snek.food    = (point){{tim.w / 8, tim.h / 2}};
+    snek.look    = (point){{1, 0}};
+}
+
+static void game(void) {
+    // update game state about every 10 ms
+    int64_t tick = time_us() / 100000;
+    if (snek.tick != tick) {
+        snek.tick = tick;
+        // move one unit
+        memmove(snek.body + 1, snek.body, sizeof(snek.body) - sizeof(point));
+        snek.body[0].x = snek.body[1].x + snek.look.x;
+        snek.body[0].y = snek.body[1].y + snek.look.y;
+        // self crash
+        bool crash = false;
+        for (int i = 1; i < snek.len; i++) {
+            crash |= snek.body[0].xy == snek.body[i].xy;
+        }
+        // border crash
+        crash |= snek.body[0].x < 0 || snek.body[0].x >= tim.w / 2 ||
+                 snek.body[0].y < 0 || snek.body[0].y >= tim.h;
+        snek.state = crash ? OVER : snek.state;
+        // food
+        if (snek.food.xy == snek.body[0].xy) {
+            snek.len    = MIN(snek.len + 2, ARRAY_SIZE(snek.body));
+            snek.food.x = rand() % (tim.w / 2 - 2) + 1;
+            snek.food.y = rand() % (tim.h - 2) + 1;
+        }
+    }
+
+    // draw
+    if (tim.event.type == DRAW_EVENT) {
+        // food
+        draw_chr(cell(" ", 0, 0xc5), snek.food.x * 2 + 0, snek.food.y);
+        draw_chr(cell(" ", 0, 0xc5), snek.food.x * 2 + 1, snek.food.y);
+        // snek
+        struct cell s = cell(" ", 0, 0);
+        for (int i = 0; i < snek.len; i++) {
+            s.bg  = (i / 2) % 2 ? 0xe3 : 0xea;
+            int x = snek.body[i].x * 2;
+            int y = snek.body[i].y;
+            draw_chr(s, x + 0, y);
+            draw_chr(s, x + 1, y);
+        }
+    }
+
+    // user input
+    if (tim.event.type == KEY_EVENT) {
+        int key = tim.event.key;
+        if ((key == RIGHT_KEY || key == 'd') && snek.look.x != -1) {
+            snek.look = (point){{1, 0}};
+        } else if ((key == LEFT_KEY || key == 'a') && snek.look.x != 1) {
+            snek.look = (point){{-1, 0}};
+        } else if ((key == DOWN_KEY || key == 's') && snek.look.y != -1) {
+            snek.look = (point){{0, 1}};
+        } else if ((key == UP_KEY || key == 'w')  && snek.look.y != 1) {
+            snek.look = (point){{0, -1}};
+        }
+    }
+}
+
+static void menu(void) {
+    scope(A, A, 20, 13) {
+        char* lbl = snek.state == OVER ? "GAME OVER" : "SNEK - THE GAME";
+        char* btn = snek.state == PAUSE ? "Resume" : "Play";
+        label(lbl, A, 0, A, A, BTN);
+        if (button(btn, A, 2, 20, 5, BTN) || is_key_press(ENTER_KEY)) {
+            if (snek.state != PAUSE) {
+                start();
+            }
+            snek.state = RUN;
+        }
+        if (button("Exit", A, 8, 20, 5, BTN) || is_key_press(ESCAPE_KEY)) {
+            exit(0);
+        }
+    }
+}
+
+int main(void) {
+    // draw every 10 ms
+    while (tim_run(10)) {
+        struct cell bg = cell(" ", 0, BG);
+        draw_lot(bg, 0, 0, tim.w, tim.h);
+
+        if (snek.state == RUN) {
+            game();
+        } else {
+            menu();
+        }
+
+        if (is_key_press(ESCAPE_KEY)) {
+            snek.state = PAUSE;
+        }
+    }
+}
+