l********r
发帖数: 140 | 1 其实好像是基本的平面几何问题啦，谁知道答案？
There is a rectangle (rectangle A) on a 2D space, with known width and
height.
Let's assume its upper left corner is (0, 0).
There is a point (point P) inside this rectangle, at (x,y).
Now, let's rotate rectangle A by k degree (k between 0 and 360), using point
P as center for rotation. For the resulting rectangle, let's get its
bounding rectangle as C.
Assume the bounding rectangle C's upper left point is our new (0, 0), what
are the new location of point A? | g*********e
发帖数: 14401 | | b******u
发帖数: 81 | 3 The new location of point P ( not A) is (x,y) | C***U
发帖数: 2406 | 4 你这个咋的出来的？？？
【在 b******u 的大作中提到】
: The new location of point P ( not A) is (x,y)
| C***U
发帖数: 2406 | 5 参看下图
用下sin应该就算出来了
point
【在 l********r 的大作中提到】
: 其实好像是基本的平面几何问题啦，谁知道答案？
: There is a rectangle (rectangle A) on a 2D space, with known width and
: height.
: Let's assume its upper left corner is (0, 0).
: There is a point (point P) inside this rectangle, at (x,y).
: Now, let's rotate rectangle A by k degree (k between 0 and 360), using point
: P as center for rotation. For the resulting rectangle, let's get its
: bounding rectangle as C.
: Assume the bounding rectangle C's upper left point is our new (0, 0), what
: are the new location of point A?
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