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Dependencies:   mbed

Ball/Ball.cpp@12:b3ec47d606a5, 2019-05-09 (annotated)

Committer:
kocemax
Date:
Thu May 09 11:41:58 2019 +0000
Revision:
12:b3ec47d606a5
Parent:
10:da5743dfb137
Child:
13:3585d2ea4ff4
Had to fix more of the comments, to improve the documentation.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
kocemax 2:006a2ddfabb6 1 #include "Ball.h"
kocemax 8:9b77eea95088 2 #include "Paddle.h"
kocemax 8:9b77eea95088 3 #include <math.h>
kocemax 2:006a2ddfabb6 4
kocemax 8:9b77eea95088 5 /** Constructor */
kocemax 2:006a2ddfabb6 6 Ball::Ball()
kocemax 2:006a2ddfabb6 7 {
kocemax 12:b3ec47d606a5 8 reset(); // initial parameters of ball
kocemax 2:006a2ddfabb6 9 }
kocemax 2:006a2ddfabb6 10
kocemax 8:9b77eea95088 11 /** Destructor - nothing happens here */
kocemax 2:006a2ddfabb6 12 Ball::~Ball()
kocemax 2:006a2ddfabb6 13 {
kocemax 2:006a2ddfabb6 14 }
kocemax 2:006a2ddfabb6 15
kocemax 8:9b77eea95088 16 /** Ball screen edge detection and movement */
kocemax 7:cd3cafda3dd4 17 void Ball::move()
kocemax 7:cd3cafda3dd4 18 {
kocemax 6:39bda45efeed 19 GameObject::move();
kocemax 10:da5743dfb137 20
kocemax 12:b3ec47d606a5 21 // Right edge
kocemax 7:cd3cafda3dd4 22 if (pos.x > WIDTH-1) {
kocemax 8:9b77eea95088 23 velocity.x = -velocity.x;
kocemax 8:9b77eea95088 24 pos.x = WIDTH-1;
kocemax 10:da5743dfb137 25 }
kocemax 12:b3ec47d606a5 26 // Left edge
kocemax 10:da5743dfb137 27 else if(pos.x < 1) {
kocemax 8:9b77eea95088 28 velocity.x = -velocity.x;
kocemax 8:9b77eea95088 29 pos.x = 1;
kocemax 2:006a2ddfabb6 30 }
kocemax 12:b3ec47d606a5 31 // Top edge
kocemax 7:cd3cafda3dd4 32 if (pos.y < 1) {
kocemax 8:9b77eea95088 33 velocity.y = -velocity.y;
kocemax 8:9b77eea95088 34 pos.y = 1;
kocemax 10:da5743dfb137 35 }
kocemax 12:b3ec47d606a5 36 // Bottom edge
kocemax 10:da5743dfb137 37 else if (pos.y > HEIGHT-1) {
kocemax 8:9b77eea95088 38 velocity.y = -velocity.y;
kocemax 8:9b77eea95088 39 pos.y = HEIGHT-1;
kocemax 2:006a2ddfabb6 40 }
kocemax 3:fe856d0890ee 41 }
kocemax 3:fe856d0890ee 42
kocemax 8:9b77eea95088 43
kocemax 8:9b77eea95088 44 #define PI 3.14159265
kocemax 8:9b77eea95088 45 float Deg2Rad = PI / 180;
kocemax 8:9b77eea95088 46 float Rad2Deg = 180 / PI;
kocemax 8:9b77eea95088 47
kocemax 12:b3ec47d606a5 48 // NOTE: This is how our coordinate system is setup.
kocemax 12:b3ec47d606a5 49 // angles go clock-wise, right is zero, up is -pi/2, down is pi/2
kocemax 12:b3ec47d606a5 50 // printf("angle of down: %.02f\n", atan2(1.f, 0));
kocemax 12:b3ec47d606a5 51 // printf("angle of right: %.02f\n", atan2(0.f, 1));
kocemax 12:b3ec47d606a5 52 // printf("angle of up: %.02f\n", atan2(-1.f, 0));
kocemax 8:9b77eea95088 53
kocemax 12:b3ec47d606a5 54 // Standard rotation of a vector by given degrees */
kocemax 12:b3ec47d606a5 55 // Example of this function to play around with: https://repl.it/repls/HopefulTrimWordprocessing */
kocemax 8:9b77eea95088 56 void Rotate(Vector2D& v, float degrees)
kocemax 8:9b77eea95088 57 {
kocemax 12:b3ec47d606a5 58 float s = (float)sin(degrees * Deg2Rad); // stores sin value betweem -1 and 1
kocemax 12:b3ec47d606a5 59 float c = (float)cos(degrees * Deg2Rad); // stores cos value betweem -1 and 1
kocemax 8:9b77eea95088 60
kocemax 12:b3ec47d606a5 61 float tx = v.x; // 2D Vector (tx, ty) for the velocity
kocemax 8:9b77eea95088 62 float ty = v.y;
kocemax 8:9b77eea95088 63
kocemax 12:b3ec47d606a5 64 // Rotation: Multiply vector by rotation matrix
kocemax 8:9b77eea95088 65 v.x = (c * tx) - (s * ty);
kocemax 8:9b77eea95088 66 v.y = (s * tx) + (c * ty);
kocemax 8:9b77eea95088 67 }
kocemax 8:9b77eea95088 68
kocemax 8:9b77eea95088 69 /** Sets upper and lower boundary for angle
kocemax 8:9b77eea95088 70 * @return clamped angle between sane boundaries
kocemax 8:9b77eea95088 71 */
kocemax 8:9b77eea95088 72 float clamp(float x, float minn, float maxx)
kocemax 3:fe856d0890ee 73 {
kocemax 8:9b77eea95088 74 return min(max(x, minn), maxx);
kocemax 8:9b77eea95088 75 }
kocemax 8:9b77eea95088 76
kocemax 8:9b77eea95088 77
kocemax 8:9b77eea95088 78
kocemax 8:9b77eea95088 79 /** Collision detection between ball and paddle */
kocemax 8:9b77eea95088 80 void Ball::hitPad(Paddle &paddle)
kocemax 8:9b77eea95088 81 {
kocemax 8:9b77eea95088 82 const Vector2D& posPad = paddle.getPos();
kocemax 9:f720f5d87420 83 if (pos.y >= posPad.y - 1 && (pos.x >= posPad.x && pos.x <= posPad.x + paddle.getW())) {
kocemax 12:b3ec47d606a5 84 // We hit the pad
kocemax 8:9b77eea95088 85
kocemax 12:b3ec47d606a5 86 // First: rotate about paddle's surface normal (flip upward)
kocemax 8:9b77eea95088 87 velocity.y = -velocity.y;
kocemax 8:9b77eea95088 88
kocemax 12:b3ec47d606a5 89 // Change angle based on distance to center
kocemax 12:b3ec47d606a5 90 float distanceSensitivity = 120; // Add at most this many degrees
kocemax 12:b3ec47d606a5 91 float maxDx = paddle.getW()/2; // Maximum distance from centre
kocemax 12:b3ec47d606a5 92 float cx = posPad.x + paddle.getW()/2.0f; // Maximum distance from current paddle centre
kocemax 12:b3ec47d606a5 93 float dx = pos.x - cx; // Positive dx means right of center, 0 means at center
kocemax 8:9b77eea95088 94
kocemax 12:b3ec47d606a5 95 float dangle = dx/maxDx * distanceSensitivity; // Delta angle, meaning change in angle
kocemax 12:b3ec47d606a5 96 float currentAngle = atan2(velocity.y, velocity.x)*Rad2Deg; // Angle of our original outgoing velocity vector
kocemax 12:b3ec47d606a5 97 float newAngle = currentAngle + dangle; // The current angle + the change in the angle
kocemax 8:9b77eea95088 98
kocemax 8:9b77eea95088 99 //printf("angle: %.02f %.02f, %.02f\n", dx, currentAngle, newAngle);
kocemax 8:9b77eea95088 100
kocemax 8:9b77eea95088 101
kocemax 12:b3ec47d606a5 102 // Always clamp angle in sane boundaries
kocemax 12:b3ec47d606a5 103 newAngle = clamp(newAngle, -160, -20); // Clamp to the range of an upward facing cone (NOTE: -90 degrees is up)
kocemax 8:9b77eea95088 104
kocemax 12:b3ec47d606a5 105 // Rotate the outgoing vector by the clamped dangle
kocemax 8:9b77eea95088 106 dangle = newAngle - currentAngle;
kocemax 8:9b77eea95088 107 Rotate(velocity, dangle);
kocemax 8:9b77eea95088 108
kocemax 2:006a2ddfabb6 109 }
kocemax 2:006a2ddfabb6 110
kocemax 6:39bda45efeed 111 }
kocemax 6:39bda45efeed 112
kocemax 8:9b77eea95088 113 /** Randomizes the initial x-direction of the ball */
kocemax 6:39bda45efeed 114 int Ball::randomize()
kocemax 4:0e01cbb95434 115 {
kocemax 12:b3ec47d606a5 116 AnalogIn noisy(PTB0); // Disconnected pin so will have random noise
kocemax 12:b3ec47d606a5 117 srand(1000000*noisy.read()); // Read the random noise and seed
kocemax 12:b3ec47d606a5 118 int direction = rand() % 2; // Randomise initial direction
kocemax 12:b3ec47d606a5 119 int movement; // Int to store the x-direction
kocemax 7:cd3cafda3dd4 120 if (direction == 0) {
kocemax 6:39bda45efeed 121 movement = -1;
kocemax 7:cd3cafda3dd4 122 } else if (direction == 1) {
kocemax 6:39bda45efeed 123 movement = 1;
kocemax 6:39bda45efeed 124 }
kocemax 7:cd3cafda3dd4 125 return movement;
kocemax 6:39bda45efeed 126 }
kocemax 6:39bda45efeed 127
kocemax 8:9b77eea95088 128 /** Resets ball's initial parameters when game is over / lost */
kocemax 7:cd3cafda3dd4 129 void Ball::reset()
kocemax 6:39bda45efeed 130 {
kocemax 12:b3ec47d606a5 131 pos.x = WIDTH/2; // initial position of ball on x-axis
kocemax 12:b3ec47d606a5 132 pos.y = HEIGHT - GAP - 2; // initial position of ball on y-axis
kocemax 12:b3ec47d606a5 133 velocity.x = randomize(); // initial x-velocity of ball
kocemax 12:b3ec47d606a5 134 velocity.y = -1; // initial y-velocity of ball
kocemax 12:b3ec47d606a5 135 w = 1; // width of the ball
kocemax 12:b3ec47d606a5 136 h = 1; // height of the ball
kocemax 2:006a2ddfabb6 137 }