Diff: Ball/Ball.cpp

Revision:

38:a85bc227b907

Parent:

29:42651f87522b

Child:

40:a1cdb6ab08af

--- a/Ball/Ball.cpp	Mon May 06 21:44:49 2019 +0000
+++ b/Ball/Ball.cpp	Thu May 09 01:09:18 2019 +0000
@@ -8,16 +8,16 @@
 
 void Ball::init(int radius){
     _radius = radius;
-    _x = 42;
+    _x = 42;            //start ball in the centre of the screen
     _y = 24;
-    _velocity.x = 0;
-    _velocity.y = 0;
-    _ball_speed = 5;
+    _velocity.x = 0;    //initially have the velocity as 0 until the
+    _velocity.y = 0;    //accelerometer senses otherwise
+    _ball_speed = 5;    //medium sensitivity to tilt input
 }
 
 void Ball::draw(N5110 &lcd){
     int radius = get_radius();
-    lcd.drawCircle(_x, _y, radius, FILL_BLACK);
+    lcd.drawCircle(_x, _y, radius, FILL_BLACK);     //draw black circle at coord (x, y) with preset radius 
 }
 
 void Ball::read_input(FXOS8700CQ &accelerometer){
@@ -30,49 +30,49 @@
 
 void Ball::update(){
     int RADIUS = get_radius();
-    _x += _velocity.x;
+    _x += _velocity.x;          //update position based on how much tilt inputted
     _y += _velocity.y;
-    if (_x < RADIUS){ _x = RADIUS;}     //check wall collisions
-    if (_x > 84 - RADIUS){ _x = 83 - RADIUS;}
-    if (_y < RADIUS){ _y = RADIUS;}
-    if (_y > 48 - RADIUS){ _y = 47 - RADIUS;}
+    if (_x < RADIUS){ _x = RADIUS;}             //check wall collisions
+    if (_x > 84 - RADIUS){ _x = 83 - RADIUS;}   //if ball position is going to
+    if (_y < RADIUS){ _y = RADIUS;}             //exceed boundaries of the screen
+    if (_y > 48 - RADIUS){ _y = 47 - RADIUS;}   //then fix it to the edge of the screen
     printf("ball speed = %d\n", _ball_speed);
 }
 
 Vector2D Ball::get_position(){
-    Vector2D pos = {_x, _y};
+    Vector2D pos = {_x, _y};    //combine x and y into Vector2D
     return pos;
 }
 
 Vector2D Ball::get_velocity(){
-    Vector2D vel = {_velocity.x, _velocity.y};
+    Vector2D vel = {_velocity.x, _velocity.y};      //combine velocity.x and .y into a Vector2D
     return vel;
 }
 
 int Ball::get_radius(){
-    int radius = _radius;
+    int radius = _radius;       //find from private member variable
     return radius;
 }
 
 int Ball::get_ball_speed(){
-    int ball_speed = _ball_speed;
+    int ball_speed = _ball_speed;       //find from private member variable
     return ball_speed;
 }
 
 void Ball::set_ball_speed(int ball_speed){
-    _ball_speed = ball_speed;
+    _ball_speed = ball_speed;           //update private member variable with user input
 }
 
 void Ball::set_velocity(Vector2D vel){
-    _velocity.x = vel.x;
-    _velocity.y = vel.y;
+    _velocity.x = vel.x;                //must pass each part of the struct individually,
+    _velocity.y = vel.y;                //can't pass both at once
 }
 
 void Ball::set_position(Vector2D pos){
-    _x = pos.x;
+    _x = pos.x;         //as with set_velocity
     _y = pos.y;
 }
 
 void Ball::set_radius(int radius){
-    _radius = radius;
+    _radius = radius;       //don't use in code, other than initially where radius is defined using #define in main.cpp
 }
\ No newline at end of file