Create snake game.cpp

snake_game.cpp

@@ -0,0 +1,218 @@
+#include <iostream>
+#include <conio.h>
+using namespace std;
+
+void run();
+void printMap();
+void initMap();
+void move(int dx, int dy);
+void update();
+void changeDirection(char key);
+void clearScreen();
+void generateFood();
+
+char getMapValue(int value);
+
+// Map dimensions
+const int mapwidth = 20;
+const int mapheight = 20;
+
+const int size = mapwidth * mapheight;
+
+// The tile values for the map
+int map[size];
+
+// Snake head details
+int headxpos;
+int headypos;
+int direction;
+
+// Amount of food the snake has (How long the body is)
+int food = 4;
+
+// Determine if game is running
+bool running;
+
+int main()
+{
+    run();
+    return 0;
+}
+
+// Main game function
+void run()
+{
+    // Initialize the map
+    initMap();
+    running = true;
+    while (running) {
+        // If a key is pressed
+        if (kbhit()) {
+            // Change to direction determined by key pressed
+            changeDirection(getch());
+        }
+        // Update the map
+        update();
+
+        // Clear the screen
+        clearScreen();
+
+        // Print the map
+        printMap();
+
+        // delay 0.4 seconds
+        _sleep(400);
+    }
+
+    // Game Text
+    cout << "\t\tGame Over!" << endl << "\t\tYour score is: " << food;
+
+    // Stop console from closing instantly
+    cin.ignore();
+}
+
+// Changes snake direction from input
+void changeDirection(char key) {
+    /*
+      W
+    A + D
+      S
+      1
+    4 + 2
+      3
+    */
+    switch (key) {
+    case 'w':
+        if (direction != 2) direction = 0;
+        break;
+    case 'd':
+        if (direction != 3) direction = 1;
+        break;
+    case 's':
+        if (direction != 4) direction = 2;
+        break;
+    case 'a':
+        if (direction != 5) direction = 3;
+        break;
+    }
+}
+
+// Moves snake head to new location
+void move(int dx, int dy) {
+    // determine new head position
+    int newx = headxpos + dx;
+    int newy = headypos + dy;
+
+    // Check if there is food at location
+    if (map[newx + newy * mapwidth] == -2) {
+        // Increase food value (body length)
+        food++;
+
+        // Generate new food on map
+        generateFood();
+    }
+
+    // Check location is free
+    else if (map[newx + newy * mapwidth] != 0) {
+        running = false;
+    }
+
+    // Move head to new location
+    headxpos = newx;
+    headypos = newy;
+    map[headxpos + headypos * mapwidth] = food + 1;
+
+}
+
+// Clears screen
+void clearScreen() {
+    // Clear the screen
+    system("cls");
+}
+
+// Generates new food on map
+void generateFood() {
+    int x = 0;
+    int y = 0;
+    do {
+        // Generate random x and y values within the map
+        x = rand() % (mapwidth - 2) + 1;
+        y = rand() % (mapheight - 2) + 1;
+
+        // If location is not free try again
+    } while (map[x + y * mapwidth] != 0);
+
+    // Place new food
+    map[x + y * mapwidth] = -2;
+}
+
+// Updates the map
+void update() {
+    // Move in direction indicated
+    switch (direction) {
+    case 0: move(-1, 0);
+        break;
+    case 1: move(0, 1);
+        break;
+    case 2: move(1, 0);
+        break;
+    case 3: move(0, -1);
+        break;
+    }
+
+    // Reduce snake values on map by 1
+    for (int i = 0; i < size; i++) {
+        if (map[i] > 0) map[i]--;
+    }
+}
+
+// Initializes map
+void initMap()
+{
+    // Places the initual head location in middle of map
+    headxpos = mapwidth / 2;
+    headypos = mapheight / 2;
+    map[headxpos + headypos * mapwidth] = 1;
+
+    // Places top and bottom walls 
+    for (int x = 0; x < mapwidth; ++x) {
+        map[x] = -1;
+        map[x + (mapheight - 1) * mapwidth] = -1;
+    }
+
+    // Places left and right walls
+    for (int y = 0; y < mapheight; y++) {
+        map[0 + y * mapwidth] = -1;
+        map[(mapwidth - 1) + y * mapwidth] = -1;
+    }
+
+    // Generates first food
+    generateFood();
+}
+
+// Prints the map to console
+void printMap()
+{
+    for (int x = 0; x < mapwidth; ++x) {
+        for (int y = 0; y < mapheight; ++y) {
+            // Prints the value at current x,y location
+            cout << getMapValue(map[x + y * mapwidth]);
+        }
+        // Ends the line for next x value
+        cout << endl;
+    }
+}
+
+// Returns graphical character for display from map value
+char getMapValue(int value)
+{
+    // Returns a part of snake body
+    if (value > 0) return 'o';
+
+    switch (value) {
+        // Return wall
+    case -1: return 'X';
+        // Return food
+    case -2: return 'O';
+    }
+}