Ball.cpp

00001 #include "Ball.h"
00002 #include "Racket.h"
00003 
00004 /**
00005  * @brief
00006  * @note
00007  * @param
00008  * @retval
00009  */
00010 Ball::Ball(int s /*= 8*/, float v /*= 8*/, uint16_t clr /*= TFT_WHITE*/ ) :
00011     size(s),
00012     velocity(v),
00013     color(clr),
00014     xPos(320 / 2),
00015     yPos(240 / 2),
00016     xPosOld(320 / 2),
00017     yPosOld(240 / 2),
00018     xDir(-1),
00019     yDir(1)
00020 { }
00021 
00022 /**
00023  * @brief
00024  * @note
00025  * @param
00026  * @retval
00027  */
00028 void Ball::home()
00029 {
00030     xPos = 320 / 2;
00031     yPos = 240 / 2;
00032     xPosOld = xPos;
00033     yPosOld = yPos;
00034     xDir = -1;
00035     yDir = 1;
00036 }
00037 
00038 /**
00039  * @brief
00040  * @note
00041  * @param
00042  * @retval
00043  */
00044 bool Ball::move(Racket* rkt)
00045 {
00046     xPosOld = xPos;
00047     yPosOld = yPos;
00048     xPos += xDir * velocity;
00049     yPos += yDir * velocity;
00050 
00051     // hit by racket?
00052     if
00053     (
00054         rkt->xPos - rkt->width / 2 < xPos + size / 2 &&
00055         xPos + size / 2 < rkt->xPos &&
00056         rkt->yPos - rkt->height / 2 < yPos + size / 2 &&
00057         yPos - size / 2 < rkt->yPos + rkt->height / 2
00058     ) {
00059         xPos = rkt->xPos - rkt->width / 2 - size / 2;
00060         xDir = -fabs(xDir); // force it to be negative
00061     }
00062 
00063     // missed racket?
00064     if (xPos > 320) {
00065         xPos = 320 / 2;
00066         yPos = 240 / 2;
00067         xDir = -1;
00068         yDir = 1;
00069         return true;
00070     }
00071 
00072     // hit left wall?
00073     if (xPos - size / 2 < 0) {
00074         xPos = size / 2;
00075         xDir = fabs(xDir);  // force it to be positive
00076     }
00077 
00078     // hit bottom wall?
00079     if (yPos + size / 2 > 240) {
00080         yPos = 240 - size / 2;
00081         yDir = -fabs(yDir); // force it to be negative
00082     }
00083 
00084     // hit top wall?
00085     if (yPos - size / 2 < 0) {
00086         yPos = size / 2;
00087         yDir = fabs(yDir);  // force it to be positive
00088     }
00089 
00090     // make sure that length of dir stays at 1
00091     vec2_norm(xDir, yDir);
00092 
00093     return false;
00094 }
00095 
00096 /**
00097  * @brief
00098  * @note
00099  * @param
00100  * @retval
00101  */
00102 void Ball::paint()
00103 {
00104     tft_boxfill(xPosOld - size / 2, yPosOld - size / 2, xPosOld + size / 2, yPosOld + size / 2, TFT_BLACK); // hide ball at old position
00105     tft_boxfill(xPos - size / 2, yPos - size / 2, xPos + size / 2, yPos + size / 2, TFT_WHITE); // draw ball at new position
00106 }
00107 
00108 /**
00109  * @brief
00110  * @note
00111  * @param
00112  * @retval
00113  */
00114 void Ball::vec2_norm(float& x, float& y)
00115 {
00116     // sets vector's length to 1 (which means that x + y = 1)
00117     float   length = sqrt((x * x) + (y * y));
00118     if (length != 0.0f) {
00119         length = 1.0f / length;
00120         x *= length;
00121         y *= length;
00122     }
00123 }