测试两个矩形是否相交的快速方法是什么?
What's a fast way to test if 2 rectangles are intersecting?
网上一搜就找到了这个单行代码(WOOT！)，但我不明白如何用Javascript编写它，它似乎是用一种古老的C++形式编写的.
A search on the internet came up with this one-liner (WOOT!), but I don't understand how to write it in Javascript, it seems to be written in an ancient form of C++.
struct
{
LONG left;
LONG top;
LONG right;
LONG bottom;
} RECT;
bool IntersectRect(const RECT * r1, const RECT * r2)
{
return ! ( r2->left > r1->right
|| r2->right < r1->left
|| r2->top > r1->bottom
|| r2->bottom < r1->top
);
}
这就是将代码转换为 JavaScript 的方式.请注意，正如评论所建议的那样，您的代码和文章中的代码有错别字.具体 r2->right left 应该是 r2->right <;r1->left 和 r2->bottom top 应该是 r2->bottom r1->top 使函数起作用.
This is how that code can be translated to JavaScript. Note that there is a typo in your code, and in that of the article, as the comments have suggested. Specifically r2->right left should be r2->right < r1->left and r2->bottom top should be r2->bottom < r1->top for the function to work.
function intersectRect(r1, r2) {
return !(r2.left > r1.right ||
r2.right < r1.left ||
r2.top > r1.bottom ||
r2.bottom < r1.top);
}
测试用例:
var rectA = {
left: 10,
top: 10,
right: 30,
bottom: 30
};
var rectB = {
left: 20,
top: 20,
right: 50,
bottom: 50
};
var rectC = {
left: 70,
top: 70,
right: 90,
bottom: 90
};
intersectRect(rectA, rectB); // returns true
intersectRect(rectA, rectC); // returns false
这篇关于快速矩形到矩形交集的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持跟版网！