Question

这里我正在计算演员和触摸点之间的度数，并将此度数传递给演员作为旋转角度。我希望演员应该指向手指触摸或手指拖动方向。（考虑我通过手指触摸拉动公交车在道路上拖动）

float degrees = (float) ((Math.atan2(touchPoint.x - crocodile.position.x, -(touchPoint.y - crocodile.position.y)) * 180.0d / Math.PI));

其计算程度适当。只有在它之间有点不同程度。所以，当结果与预期的结果完全不同时，我的演员会起伏不定。

我打印的结果是：

块引用

    degree is :: 141.93233
    degree is :: 180.0
    degree is :: 180.0
    degree is :: 158.61426
    degree is :: 90.0
    degree is :: 180.0
    degree is :: 180.0
    degree is :: 90.0
    degree is :: 180.0
    degree is :: 180.0
    degree is :: 180.0
    degree is :: 141.93057
    degree is :: 180.0
    degree is :: 180.0
    degree is :: 180.0
    degree is :: 141.93306
    degree is :: 180.0
    degree is :: 180.0
    degree is :: 141.93257
    degree is :: 180.0
    degree is :: 180.0
    degree is :: 141.93134
    degree is :: 141.93257
    degree is :: 180.0
    degree is :: 180.0
    degree is :: 180.0
    degree is :: 141.93134
    degree is :: 180.0
    degree is :: 180.0
    degree is :: 141.93306
    degree is :: 180.0
    degree is :: 180.0
    degree is :: 141.93257
    degree is :: 180.0
    degree is :: 141.93134
    degree is :: 180.0
    degree is :: 180.0
    degree is :: 141.93257
    degree is :: 180.0
    degree is :: 180.0
    degree is :: 141.93257
    degree is :: 180.0
    degree is :: 141.93134
    degree is :: 180.0
    degree is :: 141.93257
    degree is :: 180.0
    degree is :: 180.0
    degree is :: 141.93008
    degree is :: 180.0
    degree is :: 180.0
    degree is :: 141.93306
    degree is :: 180.0
    degree is :: 180.0
    degree is :: 141.93257
    degree is :: 180.0
    degree is :: 180.0
    degree is :: 180.0
    degree is :: 141.93134
    degree is :: 180.0
    degree is :: 180.0
    degree is :: 180.0
    degree is :: 180.0
    degree is :: 180.0
    degree is :: 180.0
    degree is :: 180.0

现在，180和141为什么它会随着这些值而波动。考虑到我一直期望141或者不断地在上面的公式中需要改变。

Answer 1

第一个参数必须是y，第二个参数是x。

double atan2(double y, double x)

Atan2实际上是指定y / x

的反正切函数

因为通常第一个参数是y。

此外，当您交换x和y时，您可以获得适当的学位，因为在某些边界中，如x <0和y <0，它不会交换或不交换。

Look here for more explanation

Answer 2

结合问题和答案帮助我快速解决问题。只是为了澄清一点解决方案：

double degrees = Math.atan2(
    towards.getY() - pointer.getY(),
    towards.getX() - pointer.getX()
) * 180.0d / Math.PI;
pointer.setRotation((float) degrees);

另请注意，要围绕中间旋转，您需要执行以下操作：

pointer.setOrigin(Align.center);

Libgdx两点之间的度数计算

2 个答案: