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POcalculate moving object inside box
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copied!<p>I have an object that has: start location: (X0,Y0) and speed: (Vx, Vy)</p> <p>it is trapped inside a box: boxWidth, boxHeight</p> <p>when the object hits the border of the box it will flip direction.</p> <p>ie: object has speed: (1,3) now it hits the top of the box now it's speed will be: (1,-3) now lets say it hitted the right of the box and it's speed will be: (-1, -3)</p> <p>I already made a sekeleton for the point class.</p> <p>I would need a function that I will give it an "n" time and t will return me the current object location after that time:</p> <p>my class:</p> <pre><code>class Point { protected $x0; protected $y0; protected $vx; protected $vy; protected $currentX; protected $currentY; protected $blockWide; protected $blockHeight; public function __construct($x0, $y0, $vx, $vy, $blockHeight, $blockWide) { $this->x0 = $x0; $this->y0 = $y0; $this->vx = $vx; $this->vy = $vy; $this->blockHeight = $blockHeight; $this->blockWide = $blockWide; $this->currentX = $x0; $this->currentY = $y0; } public function getLoc($time) { $this->currentX = $this->getLocX($time); $this->currentY = $this->getLocY($time); } protected function getLocX($time) { $direction = 1; $flips = 0; $distance = $this->vx * $time; if ( $this->blockWide - $this->x0) return 1; } protected function getLocY($time) { return 0; } public function printAsPoint() { echo '(',$this->currentX,',',$this->currentY,')'; } } </code></pre> <p>I simply dont have an idea on how to calculate it with the starting location, speed, and speed flips that will happen each time the point will reach the borders.</p> <p>some code from your posts:</p> <pre><code>protected function getLocX($time) { $corPos = $this->x0 + $time * $this->vx; $modulo = $corPos%(2*$this->blockWide); if($modulo > $this->blockWide) $corPos = 2*$this->blockWide - $modulo; if($modulo < $this->blockWide) $corPos = $modulo; if($modulo == $this->blockWide) $corPos = $modulo; return $corPos; } </code></pre>

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