Diff: main.cpp

Revision:

0:3acbb255fa58

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Wed Jul 13 16:06:37 2016 +0100
@@ -0,0 +1,202 @@
+/*
+The MIT License (MIT)
+
+Copyright (c) 2016 British Broadcasting Corporation.
+This software is provided by Lancaster University by arrangement with the BBC.
+
+Permission is hereby granted, free of charge, to any person obtaining a
+copy of this software and associated documentation files (the "Software"),
+to deal in the Software without restriction, including without limitation
+the rights to use, copy, modify, merge, publish, distribute, sublicense,
+and/or sell copies of the Software, and to permit persons to whom the
+Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
+*/
+
+#include "MicroBit.h"
+
+#define SNAKE_EMPTY 0
+#define SNAKE_UP    1
+#define SNAKE_LEFT  2
+#define SNAKE_RIGHT 3
+#define SNAKE_DOWN  4
+
+#define SNAKE_FRAME_DELAY   350
+#define GROWTH_SPEED        3
+
+struct Point
+{
+    int     x;
+    int     y;
+};
+
+MicroBit        uBit;
+Point           head;                 // Location of the head of our snake.
+Point           tail;                 // Location of the tail of our snake.
+Point           food;                 // Location of food.
+MicroBitImage   map(5,5);  
+
+void place_food()
+{
+    int r = uBit.random(24);
+    int x = 0; int y = 0;
+    
+    while (r > 0)
+    {
+        x = (x+1) % 5;
+        if (x == 0)
+            y = (y+1) % 5;
+            
+        if(map.getPixelValue(x,y) == SNAKE_EMPTY)
+            r--;
+    }
+    
+    food.x = x;
+    food.y = y;
+}
+
+void snake()
+{   
+    Point newHead;              // Calculated placement of new head position based on user input.    
+    int hdirection;             // Head's direction of travel
+    int tdirection;             // Tail's direction of travel
+    int snakeLength;            // number of segments in the snake.
+    int growing;                // boolean state indicating if we've just eaten some food.
+    int score;
+    
+    // Start in the middle of the screen.
+    tail.x = tail.y = 2;    
+    head.x = head.y = 2;
+    snakeLength = 1;
+    growing = 0;
+    score = 0;
+    map.clear();
+        
+    uBit.display.image.setPixelValue(head.x, head.y, 255);
+        
+    // Add some random food.    
+    place_food();
+        
+    while (1)
+    {    
+        // Flash the food is necessary;       
+        uBit.display.image.setPixelValue(food.x, food.y, uBit.systemTime() % 1000 < 500 ? 0 : 255);
+          
+        int dx = uBit.accelerometer.getX();
+        int dy = uBit.accelerometer.getY();
+        
+        newHead.x = head.x;
+        newHead.y = head.y;
+        
+        if (abs(dx) > abs(dy))
+        {
+            if(dx < 0)
+            {
+                hdirection = SNAKE_LEFT;
+                newHead.x = newHead.x == 0 ? 4 : newHead.x-1;
+            }
+            else
+            {
+                hdirection = SNAKE_RIGHT;
+                newHead.x = newHead.x == 4 ? 0 : newHead.x+1;
+            }            
+        }
+        else    
+        {
+            if(dy < 0)
+            {
+                hdirection = SNAKE_UP;
+                newHead.y = newHead.y == 0 ? 4 : newHead.y-1;
+            }
+            else
+            {
+                hdirection = SNAKE_DOWN;
+                newHead.y = newHead.y == 4 ? 0 : newHead.y+1;
+            }
+        }           
+        
+        int status = map.getPixelValue(newHead.x, newHead.y);
+        if (status == SNAKE_UP || status == SNAKE_DOWN || status == SNAKE_LEFT || status == SNAKE_RIGHT)
+        {
+            uBit.display.scroll("GAME OVER! SCORE: ");
+            uBit.display.scroll(score);
+            
+            return;            
+        }
+                                          
+        // move the head.       
+        map.setPixelValue(head.x, head.y, hdirection);
+        uBit.display.image.setPixelValue(newHead.x, newHead.y, 255);
+
+        if (growing == GROWTH_SPEED)
+        {
+            growing = 0;
+            snakeLength++;
+        }
+        else
+        {        
+            // move the tail.
+            tdirection = map.getPixelValue(tail.x,tail.y);     
+            map.setPixelValue(tail.x, tail.y, SNAKE_EMPTY);         
+            uBit.display.image.setPixelValue(tail.x, tail.y, 0);
+    
+            // Move our record of the tail's location.        
+            if (snakeLength == 1)
+            {
+                tail.x = newHead.x;
+                tail.y = newHead.y;
+            }
+            else
+            {
+                if (tdirection == SNAKE_UP)
+                    tail.y = tail.y == 0 ? 4 : tail.y-1;
+                
+                if (tdirection == SNAKE_DOWN)
+                    tail.y = tail.y == 4 ? 0 : tail.y+1;
+            
+                if (tdirection == SNAKE_LEFT)
+                    tail.x = tail.x == 0 ? 4 : tail.x-1;
+                
+                if (tdirection == SNAKE_RIGHT)
+                    tail.x = tail.x == 4 ? 0 : tail.x+1;
+            }
+        }
+
+        // Update our record of the head location and away we go!
+        head.x = newHead.x;
+        head.y = newHead.y;
+      
+        // if we've eaten some food, replace the food and grow ourselves!
+        if (head.x == food.x && head.y == food.y)
+        {
+            growing++;
+            score++;
+            place_food();
+        }
+      
+        uBit.sleep(SNAKE_FRAME_DELAY);   
+    }   
+}
+
+int main()
+{
+    // Initialise the micro:bit runtime.
+    uBit.init();
+
+    // Insert your code here!
+    uBit.display.scroll("SNAKE v1.0");
+
+    while(1)
+        snake();
+}
+