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c#xnamonogamerectanglesvector-graphics

Convert 2 vector2 points to a rectangle in xna/monogame


I have some code which will detect the start and end point of a click-and-drag action, and will save it to 2 vector2 points. I then use this code to convert:

public Rectangle toRect(Vector2 a, Vector2 b)
{
    return new Rectangle((int)a.X, (int)a.Y, (int)(b.X - a.X), (int)(b.Y - a.Y));
}

The code above does not work and googling, so far has come up inconclusive. Could anyone please provide me with some code or a formula to properly convert this?
Note: a vector2 has an x and a y, and a rectangle has an x, a y, a width, and a height.

Any help is appreciated! Thanks


Solution

  • I think you need to have additional logic in there to decide which vector to use as the top left and which to use as the bottom right.

    Try this:

        public Rectangle toRect(Vector2 a, Vector2 b)
        {
            //we need to figure out the top left and bottom right coordinates
            //we need to account for the fact that a and b could be any two opposite points of a rectangle, not always coming into this method as topleft and bottomright already.
            int smallestX = (int)Math.Min(a.X, b.X); //Smallest X
            int smallestY = (int)Math.Min(a.Y, b.Y); //Smallest Y
            int largestX = (int)Math.Max(a.X, b.X);  //Largest X
            int largestY = (int)Math.Max(a.Y, b.Y);  //Largest Y
    
            //calc the width and height
            int width = largestX - smallestX;
            int height = largestY - smallestY;
    
            //assuming Y is small at the top of screen
            return new Rectangle(smallestX, smallestY, width, height);
        }