Please tell me the code for determining the collision between a rectangle and a circle.

No language is specified, so only algorithms are indicated.

If you omit the detailed explanation in the figure below and conclude, it can be considered a collision when the center P1 of the circle enters the solid line drawn outside the rectangle (red).The light blue line corresponds to the distance r from the outer edge of the rectangle.Therefore, the corners are parallel to the rectangle, and the corners are 1/4 of the circle with radius r.

Also, please refer to the diagram below to determine if it has entered this light blue solid line.The algorithm shown here is one example, and there are other ways to build it.Also, the decision algorithm shown here is far from fast.An improvement could be to detect contact early.

There is no additional explanation for 1.Simply calculate and determine the coordinates of the four corners of the yellow area.

2 is divided into two areas, but the yellow area and the overlapping area are assumed to be orange and can be determined as one rectangle.The rest is the same as 1 and there is nothing to explain.

For 3, you can determine from one of the four angles of the red rectangle that is within the distance r.It's just a simple distance calculation, so I'll skip the detailed explanation.

That's all.