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POAndroid Math does not work
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copied!<pre><code>private void gotoPos() { spaceX = x2 - x; spaceY = y2 - y; if (Math.abs(spaceX) >= Math.abs(spaceY)) { xSpeed = Math.round(spaceX * (3/Math.abs(spaceX))); ySpeed = Math.round(spaceY * (3/Math.abs(spaceX))); } </code></pre> <p>With this code I want to move an object to the position x2 and y2. x and y is the current position of the object. spaceX is the space that is between the object and the x position it should go to. The same for spaceY. </p> <p>But I don't want the object to move more than 3 Pixels per draw.</p> <p>Example: object position: x = 35, y = 22</p> <p>Point it should go to: x2 = 79, y2 = 46</p> <p>space between them: spaceX = 79-35 = 44, spaceY = 46-22 = 24</p> <p>spaceX is bigger then spaceY so:</p> <p>xSpeed = 44 * (3/44) = 3, ySpeed = 24 * (3/44) = 1.63 = 2</p> <p>But it does not work like this. When I start the app the object does not go to x2 and y2. If I change xSpeed = spaceX; ySpeed = spaceY;</p> <p>The object moves to the position but I do not want it to go there instantly</p> <p>Complete Code:</p> <pre><code>public class Sprite { private boolean walking = true; private int actionWalk = 0; private Random rnd; private int checkIfAction; private int nextAction = 0; static final private int BMP_COLUMNS = 4; static final private int BMP_ROWS = 4; private int[] DIRECTION_TO_SPRITE_SHEET = { 1, 0, 3, 2 }; public int x=-1; private int y=-1; public int xSpeed; private int ySpeed; private int width; private int height; private int bottomSpace; private Bitmap bmp; private GameView theGameView; private int currentFrame=0; private int x2, y2; private boolean isTouched; private int spaceX, spaceY; </code></pre> <p>D</p> <pre><code>public Sprite(GameView theGameView, Bitmap bmp) { this.theGameView = theGameView; this.bmp = bmp; this.width = bmp.getWidth() / BMP_COLUMNS; this.height = bmp.getHeight() / BMP_ROWS; rnd = new Random(); xSpeed = 0; ySpeed = 0; } public void shareTouch(float xTouch, float yTouch) { x2 = (int) xTouch; y2 = (int) yTouch; isTouched = true; } private void gotoPos() { spaceX = x2 - x; spaceY = y2 - y; if (Math.abs(spaceX) >= Math.abs(spaceY)) { xSpeed = Math.round(spaceX * (3/Math.abs(spaceX))); ySpeed = Math.round(spaceY * (3/Math.abs(spaceX))); } else { xSpeed = spaceX; ySpeed = spaceY; } } </code></pre> <p>D</p> <pre><code>private void bounceOff() { bottomSpace = theGameView.getHeight() - y; if (x > theGameView.getWidth() - (width * theGameView.getDensity()) - xSpeed - bottomSpace / 2 || x + xSpeed < bottomSpace / 2) { xSpeed = -xSpeed; } x = x + xSpeed; if (y > theGameView.getHeight() - (height * theGameView.getDensity()) - ySpeed || y + ySpeed < theGameView.getHeight() / 2) { ySpeed = -ySpeed; } y = y + ySpeed; currentFrame = ++currentFrame % BMP_COLUMNS; } </code></pre> <p>d</p> <pre><code>public void onDraw(Canvas canvas) { if (x == -1) { x = (theGameView.getWidth() / 2); y = (theGameView.getHeight() / 2 + theGameView.getHeight() / 4); } if (isTouched == true) { gotoPos(); } /* if (nextAction == 100) { action(); nextAction = 0; } nextAction += 1;*/ bounceOff(); int sourceX, sourceY; if (walking == true) { sourceX = currentFrame * width; } else { sourceX = 0; } sourceY = getAnimationRow() * height; Rect source = new Rect(sourceX, sourceY, sourceX + width, sourceY + height); Rect destine = new Rect(x, y, (int) (x + (width * theGameView.getDensity())), (int) (y + (height * theGameView.getDensity()))); canvas.drawBitmap(bmp, source, destine, null); } </code></pre> <p>d</p> <pre><code>private int getAnimationRow() { double directionDouble = (Math.atan2(xSpeed, ySpeed) / (Math.PI / 2) + 2); int spriteDir = (int) Math.round(directionDouble) % BMP_ROWS; return DIRECTION_TO_SPRITE_SHEET[spriteDir]; } </code></pre> <p>}</p>

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