Javascript angle between vectors

Calculating the Angle Between Two Points Using PaperJS

To calculate the angle, you must use two vectors. One vector should be from your current point to the previous point, and the other vector should be from your current point to the next point. To find the angle in radians, you can use Vector3.angleTo directly. This function returns the angle in radians, but you can convert it to degrees by multiplying it by a constant. This approach allows you to determine angles in any direction, such as the angle to a plane. To calculate the angle to a plane, you can use the formula a = cos^-1(n.v), where a is the angle in degrees to the normal vector of the plane.

PaperJS — angle between two points

The points provided to getAngle(point), getAngleInRadians(point), and getDirectedAngle(point) are all treated as vectors.

The output is in degrees for all methods, except for getAngleInRadians().

 point1.getDirectedAngle(point2) 

The vector between your current point and the previous point should be assigned to point1 , while point2 should represent the vector between your current point and the next point.

for segment in path.segments point1 = segment.previous.point.subtract(segment.point) point2 = segment.next.point.subtract(segment.point) angle = point1.getDirectedAngle(point2) 

Javascript — How do I calculate the angle between two, The angle between 2 points is relative to where you measure from. By subtracting P2 from P1, you’re making the angle relative to your starting point. Thus, atan2 is giving you the clockwise angle relative to the X axis. Traditionally, the X axis is the starting point for rotations, so a horizontal line has an angle of 0:

How to get the y angle between 2 vectors in Three.js?

Instead of computing the angle in radians, you may utilize Vector3.angleTo for direct calculation. As with most math functions, the value returned is in radians. However, if you prefer to get the result in degrees, you can simply multiply it by 180 degrees/pi rad= 1 before printing.

// notice that v1 is pointing to the x-axis direction. const v1 = new THREE.Vector3(10,0,0); const v2 = new THREE.Vector3(3,3,0); const v3 = new THREE.Vector3(0, 50, 23); // Alngle between v1 and v2 console.log(v1.angleTo(v2)*180/Math.PI) // The operation is comutative console.log(v2.angleTo(v1)*180/Math.PI) // An example at 90 degree console.log(v1.angleTo(v3)*180/Math.PI)

By means of ans(a — 90) , it becomes feasible to determine the angles in any direction. For instance, when you require the angle to a plane, the angle a, which is measured in degrees, can be obtained by referring to the normal vector of the plane.

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Javascript — How to calculate an angle from points?, One of the issue with getting the angle between two points or any angle is the reference you use. In maths we use a trigonometric circle with the origin to the right of the circle (a point in x=radius, y=0) and count the angle counter clockwise from 0 to 2PI. In geography the origin is the North at 0 degrees and we go clockwise …

How to find angle between two vectors on canvas?

Essentially, your objective is to align the intersection point of your two vectors with the origin, where both x and y coordinates are equal to zero.

Take a look at this picture:

The values for the points A, B, and C can be expressed as the x and y coordinates.

We can make use of the Math.atan2() function to determine the arctangent of both values. It is important to keep in mind that the y value should be the first parameter for the atan2 function.

var firstAngle = Math.atan2(-6, 0); var secondAngle = Math.atan2(2, 5); 

Subtract one from the other to obtain their difference.

var angle = secondAngle - firstAngle; 

You can obtain a radian value from this, which can be transformed into degrees using the following method:

angle = angle * 180 / Math.PI; 

Initially, it is essential to standardize both the vectors.

Once that’s done you can do

The desired angle can be obtained using the dot product operator (•) and the inverse of cosine function (arcos).

Exercise caution as the returned output will solely provide the angle’s relative and raw data without indicating which vector is positioned on the left or right.

To obtain assistance for both 2D ( z=0 ) and 3D, the Dot product can be utilized.

const dot = (p1, p2) => p1.x * p2.x + p1.y * p2.y + p1.z * p2.z; 

The magnitude can be calculated using the square magnitude ( magSq ).

const magSq = () => x ** 2 + y ** 2 + z ** 2; const mag = Math.sqrt(magSq(p)); 

After calculating the Dot product, we can proceed to normalize it. Next, use the code acos() to obtain the angle.

const angle = Math.acos(dot(p1, p2) / Math.sqrt(magSq(p1) * magSq(p2))); 

An alternative to using Math.hypot() is to utilize a specialized JS function designed for mag .

const mag = (p) => Math.hypot(p.x, p.y, p.z); 
const angle = Math.acos(dot(p1, p2) / (mag(p1) * mag(p2))); 
Example:
let a = ; let b = ; // set z != 0 for 3D let dot = (p1, p2)=> p1.x * p2.x + p1.y * p2.y + p1.z * p2.z; let magSq = () => x ** 2 + y ** 2 + z ** 2; let angle1 = Math.acos(dot(a, b) / Math.sqrt(magSq(a) * magSq(b))); console.log('1. Angle:', angle1); // 1.9513027 // . or let mag = () => Math.hypot(x, y, z); let angle2 = Math.acos(dot(a, b) / (mag(a) * mag(b))) console.log('2. Angle:', angle2); // 1.9513027

Javascript — Fastest way to find the angle between two, Edit 2 To speed up if you’re using the vectors length many times, save it as e.g. v.length = so you can get it without re-calculating again. If you know every vector will need it’s angles calculated multiple times, use the first method I wrote and cache it, i.e. v.angle = .You can then you can do v2.angle — v1.angle …

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Three js get angle between 2 vectors

javascript angle from two points

// point 1 (x1, y1) or origine of vertex // point 2 (x2, y2) var dx = x2 - x1 var dy = y2 - y1 var ang = Math.atan2(dy, dx) * 180 / Math.PI;

Angle between two vectors javascript, Angle between two vectors javascript. Ask Question Asked 5 years, 8 months ago. Modified 5 years, 8 months ago. Viewed 4k times 0 1. I have a the a dotProduct function an a magnitude function. I am struggling to combine these to get the radians between of two vectors. What I have so far is: …

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Vector.js

Vector is an open source javascript library for creating interactive graphics. View the repository, run the tests, or meet the team.

Angle Between Two Vectors Open in Sandbox

Description

This interactive demonstrates the angle formed between two vectors.

Script

/** * @title Angle Between Two Vectors * @description This interactive demonstrates the angle formed between two vectors. * @tags [math] * @ignore true */ // import Interactive from 'https://unpkg.com/@interactive-svg/library/dist/Interactive.js';  import  Interactive, getScriptName > from '../../index.js'; // Initialize the interactive  let interactive = new Interactive(getScriptName()); interactive.border = true; interactive.originX = interactive.width / 2; interactive.originY = interactive.height / 2; ; // Create a circle  let circle = interactive.circle(0, 0, 100); circle.root.style.stroke = 'none'; // Create a control  let c0 = interactive.control(0, 0); let c1 = interactive.control(circle.r * Math.cos(0), circle.r * Math.sin(0)); let c2 = interactive.control(circle.r * Math.cos(-1), circle.r * Math.sin(-1)); // c1.constrainTo( circle); // c2.constrainTo( circle); // Create a path  let path = interactive.path(''); path.root.style.fill = 'rgb(236,236,236)'; path.update = function ()   let a1 = Math.atan2(c1.y - c0.y, c1.x - c0.x);  let a2 = Math.atan2(c2.y - c0.y, c2.x - c0.x);  let angle = normalize(a2 - a1);  let largeArcFlag = (angle > Math.PI) ? false : true;  let r = circle.r / 3;  let x1 = r * Math.cos(a1) + c0.x;  let y1 = r * Math.sin(a1) + c0.y;  let x2 = r * Math.cos(a2) + c0.x;  let y2 = r * Math.sin(a2) + c0.y;  path.d = `M $c0.x> $c0.y>  L $c1.x> $c1.y>  L $x1> $y1>  A $r> $r> 0 $+largeArcFlag> 0 $x2> $y2>  L $c2.x> $c2.y>  z`; >; path.update(); path.addDependency(c0); path.addDependency(c1); path.addDependency(c2); let arrow1 = interactive.path(''); arrow1.addDependency(c0); arrow1.addDependency(c1); arrow1.update = function ()   let r = 8;  let angle = Math.atan2(c1.y - c0.y, c1.x - c0.x);  this.d = `M $c1.x + r * Math.cos(angle)> $c1.y + r * Math.sin(angle)>  L $c1.x + r * Math.cos(angle - 2 * Math.PI / 3)> $c1.y + r * Math.sin(angle - 2 * Math.PI / 3)>  L $c1.x + r * Math.cos(angle + 2 * Math.PI / 3)> $c1.y + r * Math.sin(angle + 2 * Math.PI / 3)>  Z`; >; arrow1.root.style.fill = '#0366EE'; arrow1.root.style.stroke = 'none'; arrow1.update(); let arrow2 = interactive.path(''); arrow2.addDependency(c0); arrow2.addDependency(c2); arrow2.update = function ()   let r = 8;  let angle = Math.atan2(c2.y - c0.y, c2.x - c0.x);  this.d = `M $c2.x + r * Math.cos(angle)> $c2.y + r * Math.sin(angle)>  L $c2.x + r * Math.cos(angle - 2 * Math.PI / 3)> $c2.y + r * Math.sin(angle - 2 * Math.PI / 3)>  L $c2.x + r * Math.cos(angle + 2 * Math.PI / 3)> $c2.y + r * Math.sin(angle + 2 * Math.PI / 3)>  Z`; >; arrow2.root.style.fill = '#0366EE'; arrow2.root.style.stroke = 'none'; arrow2.update(); c1.addDependency(c0); c1.update = function ()   this.x += c0.dx;  this.y += c0.dy; >; c2.addDependency(c0); c2.update = function ()   this.x += c0.dx;  this.y += c0.dy; >; circle.addDependency(c0); circle.update = function ()   this.cx += c0.dx;  this.cy += c0.dy; >; // Create a checkbox to toggle between displaying radians and degrees  let degrees = interactive.checkBox(interactive.width / 6, 125, "degrees", false); /** * Normalizes the angle to be within the range [0, 2 PI]. */ function normalize(angle)   if (angle > 0)   return angle;  >  else   return 2 * Math.PI + angle;  > > // Gets the normalized angle between zero and tau. TODO: Maybe transform the // coordinate system so that the positive y-direction is up instead of down. // UPDATE: transform = 'scale(1,-1)' applied to the main svg didn't quite work // as expected: the text element was upside down, but maybe that could be // reversed? bleh.  function getAngle()   let angle;  let a1 = Math.atan2(c1.y - circle.cy, c1.x - circle.cx);  let a2 = Math.atan2(c2.y - circle.cy, c2.x - circle.cx);  angle = 2 * Math.PI - normalize(a2 - a1);  if (degrees.value)   return (angle * 180 / Math.PI).toFixed(1) + '°';  >  else   return angle.toFixed(3) + ' rad';  > > // Create text to display the current angle. TODO: add a check-box to change // between radians and degrees  let text = interactive.text(-interactive.width / 3, 125, "test"); text.update = function ()   text.contents = `angle = $getAngle()>`; >; text.addDependency(degrees); text.addDependency(c1); text.addDependency(c2); text.update(); text.root.style.dominantBaseline = 'middle'; export  interactive, c1 >; //# sourceMappingURL=angle-between-two-vectors.js.map 

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