p5.js atan2() Function

The atan2() function in p5.js is used to calculate the angle from a specified point of origin measured from the positive x-axis. The values are returned in the range of PI to -PI as floating points. It is commonly used for orienting geometry to the position of the cursor. Syntax:
`atan2(y, x)`
Parameters: This function accepts two parameters as mentioned above and described below.
• y: It is a number that specifies the y-coordinate of the point.
• x: It is a number that specifies the x-coordinate of the point.
Return Value: It returns a number that denotes the arc tangent of the given point. Below examples illustrate the atan2() function in p5.js: Example 1:
 `function` `setup() { ``  ``createCanvas(500, 200); ``  ``textSize(18); `` ` `  ``text(``"Move the slider to observe the effects"``         ``+ ``" of the atan2() function"``, 20, 30); `` ` `  ``sliderXPos = createSlider(-200, 200, 0, 1); ``  ``sliderXPos.position(20, 50); `` ` `  ``sliderYPos = createSlider(-200, 200, 0, 1); ``  ``sliderYPos.position(20, 80); ``} `` ` `function` `draw() { ``  ``clear(); ``  ``text(``"Move the slider to observe the effects"``         ``+ ``" of the atan2() function"``, 20, 30); `` ` `  ``sliderXVal = sliderXPos.value(); ``  ``sliderYVal = sliderYPos.value(); `` ` `  ``atan2Val = atan2(sliderXVal, sliderYVal); `` ` `  ``text(``"The X position value is: "` `+ sliderXVal, 20, 140); ``  ``text(``"The Y position value is: "` `+ sliderYVal, 20, 160); ``  ``text(``"The atan2 value is: "` `+ atan2Val, 20, 180); ``} `

Output: Example 2:
 `function` `setup() { ``  ``createCanvas(500, 400); ``  ``textSize(18); ``  ` `  ``text(``"Move the mouse to see the rectangle"``        ``+ ``" align to it."``, 20, 30); ``} ``  ` `function` `draw() { ``  ``clear(); ``  ``text(``"Move the mouse to see the rectangle"``        ``+ ``" align with the mouse."``, 20, 30); ``  ` `  ``// Move the rectangle to the ``  ``// middle of the screen ``  ``translate(width / 2, height / 2); ``  ` `  ``// Use the atan2() function to find ``  ``// the value according to the mouse ``  ``// coordinates ``  ``let adjustedValue = atan2(mouseY - height / 2, ``                            ``mouseX - width / 2); ``  ``rotate(adjustedValue); ``  ` `  ``// Draw a rectangle ``  ``rect(0, 0, 50, 25); ``  ` `  ``text(adjustedValue.toFixed(4), 100, 20); ``} `

Output: Online editor: https://editor.p5js.org/ Environment Setup: https://www.geeksforgeeks.org/p5-js-soundfile-object-installation-and-methods/ Reference: https://p5js.org/reference/#/p5/atan2

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