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By : user211653
Date : November 22 2020, 03:03 PM
hop of those help? You are looking for toLocalPoint, which does most of the work for you : http://fabricjs.com/docs/fabric.Object.html#toLocalPoint
As you can see in the source of the function, it does not take into account scaling, but it does the rotation and translation of the object. code :
``````var p = canvas.getPointer(event);
var loc = target.toLocalPoint(new fabric.Point(p.x,p.y), "left", "top");

var pos_in_target = {
x : loc.x / target.getScaleX(),
y : loc.y / target.getScaleY()
};
`````` ## Why is it a good idea to use Math.min() for x, y coordinates and math.abs()

By : Sparkes
Date : March 29 2020, 07:55 AM
To fix this issue The x,y coordinates represent the position of the rectangle on a plane; they can be negative since the rectangle can be place anywhere relative to the origin (ie. 0,0 position).
The height and width of the rectangle must be positive as negative lenghts are really not defined. ## Conversion coordinates from a bound rectangle, to the coordinates of rotated rectangle contained by it

By : Malik Ali
Date : March 29 2020, 07:55 AM
This might help you I assume we're using the convention that the rotation by alpha carries the vector (1,0) toward the vector (0,1).
Suppose the vector P from the origin of the bounding rectangle to the origin of the inner rectangle is represented in the coordinate frame of the bounding rectangle as (Px, Py). In that coordinate frame, the point S has coordinates (Sx, Sy); The vector D = S - P = (Dx, Dy) = (Sx - Px, Sy - Py). ## Get X,Y coordinates from Angle & Distance ( Incorrect values using Math.cos() & Math.sin() )

By : Guirip
Date : March 29 2020, 07:55 AM
will help you I've read all accepted answers on this topic and repeated exactly the logic used in them but my results seem to be skewed and 'random'. ,
and change too often
code :
`````` Math.cos(degrees * Math.PI / 180);
Math.sin(degrees * Math.PI / 180);
``````
`````` x = center_object_x + Math.cos(degrees * Math.PI / 180);
y = center_object_y + Math.sin(degrees * Math.PI / 180);
`````` ## Understanding math: transformation world coordinates to view coordinates

By : J. Doe
Date : March 29 2020, 07:55 AM
it fixes the issue The matrix T is applied first. It translates some world coordinate P by minus the camera coordinate (call it C), giving the relative coordinate of P (call this Q) with respect to the camera (Q = P - C), in the world axes orientation.
The matrix R is then applied to Q. It performs a rotation to obtain the coordinates of Q in the camera's axes. ## Usefull way of reverting Homogeneous coordinates back to 2d?

By : Akash Verma
Date : March 29 2020, 07:55 AM
it fixes the issue One approach making use of broadcasted elementwise divisions - 