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/*The solution to draggable elements was inspired by w3schools solution on creating a [Draggable HTML Element](https://www.w3schools.com/howto/howto_js_draggable.asp).*/
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dragElement(document.getElementById('plant1'));
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dragElement(document.getElementById('plant2'));
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dragElement(document.getElementById('plant3'));
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dragElement(document.getElementById('plant4'));
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dragElement(document.getElementById('plant5'));
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dragElement(document.getElementById('plant6'));
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dragElement(document.getElementById('plant7'));
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dragElement(document.getElementById('plant8'));
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dragElement(document.getElementById('plant9'));
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dragElement(document.getElementById('plant10'));
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dragElement(document.getElementById('plant11'));
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dragElement(document.getElementById('plant12'));
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dragElement(document.getElementById('plant13'));
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dragElement(document.getElementById('plant14'));
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/*"A closure is the combination of a function bundled together (enclosed)
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with references to its surrounding state (the lexical environment).
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In other words, a closure gives you access to an outer function’s scope
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from an inner function." Create a closure so that you can track the dragged element*/
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function dragElement(terrariumElement) {
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//set 4 positions for positioning on the screen
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let pos1 = 0,
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pos2 = 0,
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pos3 = 0,
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pos4 = 0;
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terrariumElement.onpointerdown = pointerDrag;
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function pointerDrag(e) {
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e.preventDefault();
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console.log(e);
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// get the initial mouse cursor position for pos3 and pos4
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pos3 = e.clientX;
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pos4 = e.clientY;
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// when the mouse moves, start the drag
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document.onpointermove = elementDrag;
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// when the mouse is lifted, stop the drag
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document.onpointerup = stopElementDrag;
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}
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function elementDrag(e) {
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// calculate the new cursor position
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// pos1 = where the Xmouse WAS - where it IS
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pos1 = pos3 - e.clientX;
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// pos2 = where the Ymouse WAS - where it IS
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pos2 = pos4 - e.clientY;
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//reset pos3 to current location of Xmouse
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pos3 = e.clientX;
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//reset pos4 to current location of Ymouse
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pos4 = e.clientY;
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console.log(pos1, pos2, pos3, pos4);
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// set the element's new position:
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terrariumElement.style.top = terrariumElement.offsetTop - pos2 + 'px';
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terrariumElement.style.left = terrariumElement.offsetLeft - pos1 + 'px';
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}
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function stopElementDrag() {
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// stop calculating when mouse is released
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document.onpointerup = null;
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document.onpointermove = null;
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}
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}
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