Diff: GameObjects/Snake/Snake.cpp

Revision:

87:871d9fecb593

Parent:

83:329da564799a

--- a/GameObjects/Snake/Snake.cpp	Tue May 07 00:02:11 2019 +0000
+++ b/GameObjects/Snake/Snake.cpp	Wed May 08 16:39:24 2019 +0000
@@ -56,12 +56,12 @@
 
 void Snake::set_pos(Vector2D p)
 {
-    _x[0] = p.x;  //Spawns player sprite near the middle of the screen.
-    _y[0] = p.y;
+    _x[0] = p.x;  //Spawns first of the snake sprite near the middle of the screen.
+    _y[0] = p.y;  //Spawns first of thesnake sprite near the bottom of the screen.
 
-    for(int i=0; i<=8; i++)  {
-        _x[i+1] = _x[i];
-        _y[i+1] = _y[i] - 3;
+    for(int i=1; i<=9; i++)  {
+        _x[i] = _x[i-1];      //Makes them all get spawned at the same x position initially. (copies the previous snake bead)
+        _y[i] = _y[i-1] - 3;  //Makes them all get spawned 3 sprites appart in the y axis initially. (copies the previous snake bead)
     }
 }
 
@@ -69,60 +69,62 @@
 {
     Vector2D snakepos; //Stores the snake position.
 
-    for(int i = (snakeIndex + 1); i<=10; i++)  {
-        if(_length == i)  {
-            snakepos.x = _x[i - (snakeIndex + 1)];
-            snakepos.y = _y[i - (snakeIndex + 1)];
+    for(int i = snakeIndex; i<=9; i++)  {
+        if(_length == (i+1))  {
+            snakepos.x = _x[i - snakeIndex]; //Gets the index from SnakevsBlock.cpp which is basically 0 for the top beed, and 9 for the 10th beed
+            snakepos.y = _y[i - snakeIndex]; //and saves it in x[?] and y[?] which is 0 for the bottom beed and higher indexes for higher beeds.
             return snakepos;
         }
     }
     if(_length >= 10)  {
-        snakepos.x = _x[9 - snakeIndex];
-        snakepos.y = _y[9 - snakeIndex];
+        snakepos.x = _x[9 - snakeIndex]; //we know that at length = 10+ the snake doesn't look any longer, so subtracting the index from 9 will imply
+        snakepos.y = _y[9 - snakeIndex]; //the top beed is _x[9], _y[9] and the last beed (index 9) is _x[0], _y[0]
         return snakepos;
     }
-    snakepos.x = NULL;
-    snakepos.y = NULL;
+    snakepos.x = -100; //to make sure these coordinates do not interfere with any collisions as this is a default value if conditions do not satisfy,
+    snakepos.y = -100; //(NULL is in range of collisions in this game and is therefore not used.
     return snakepos;
     //printf("snakepos from player = %f %f \n", snakepos.x, snakepos.y);
 }
 
-void Snake::update(Direction d, int* b)
+void Snake::update(Direction d, int* immobile_bead_n)
 {
-    Snake::chainSnakeTogether(b);
+    _d = d; //Saves the direction of movement in a private struct _d from the SnakevsBlock.cpp.
+    
+    Snake::chainSnakeTogether(immobile_bead_n); //chains the snake beads together in hysteresis.
 
-    Snake::mooveSnake(d, b);
+    Snake::moveSnake(immobile_bead_n); //makes the top bead in the snake move according to the user input direction.
 
-    Snake::_setSnakeLimits();
+    Snake::_setSnakeLimits(); //makes the snake movement limited to the nokia screen and ensure spawn position is where we expected.
 }
 
-void Snake::chainSnakeTogether(int* b)
+void Snake::chainSnakeTogether(int* immobile_bead_n)
 {
     //this makes all of the snake beeds chained together by making the lower ones drag towards where the top one was in the previous loop
-    //the b[i] makes sure that the snake beed doesn't move if that beed is deactivated by colliding with a barrier. b[i] also signifies the specific beed number by i.
+    //the immobile_bead_n[i] makes sure that the snake beed doesn't move if that beed is deactivated by colliding with a barrier. immobile_bead_n[i] also signifies the specific beed number by i.
     for(int i=1; i<=9; i++)  {
         if((_length > i)&&(_x[i-1] != _x[i]))  {
-            if ((_x[i-1] > _x[i])&&(b[i] == 1)&&(b[i-1] == 1))  {
+            if ((_x[i-1] > _x[i])&&(immobile_bead_n[i] == 1)&&(immobile_bead_n[i-1] == 1))  {
                 _x[i-1]-=_speed;
             }
-            if ((_x[i-1] < _x[i])&&(b[i] == 1)&&(b[i-1] == 1))  {
+            if ((_x[i-1] < _x[i])&&(immobile_bead_n[i] == 1)&&(immobile_bead_n[i-1] == 1))  {
                 _x[i-1]+=_speed;
             }
         }
     }
 }
 
-void Snake::mooveSnake(Direction d, int* b)
+void Snake::moveSnake(int* immobile_bead_n)
 {
     //this makes the controls of W/E directions only exclusive to the top beed in the snake
     for(int i=0; i<=9; i++)  {
-        if((_length == i+1)&&(b[i] == 1))  {
+        if((_length == i+1)&&(immobile_bead_n[i] == 1))  {
 
-            if (d == E) {
+            if (_d == E) {
                 _x[i]+= _speed;
             }
 
-            if (d == W) {
+            if (_d == W) {
                 _x[i]-= _speed;
             }