处理板上形状的选择
我有一块板作为画布，上面画了几个形状，其中一些是三角形、圆形、矩形，但所有形状都包含在它们自己的边界分隔矩形内。
“圆将位于矩形内”
我将两个圆 A、B 放在板上，其中 A 在 B 上方并且有一些区域发生碰撞。 如果我单击与容器框相对应的 A 区域，但不是实际的 A 圆形区域，我不会选择 A 圆形，但这会阻止我选择 B，因为我的 A 容器重叠并位于 B 之上。
在事件基础框架中，我猜子事件将传递给父事件而不是兄弟事件。
所以我的选择是检查所有形状容器，这些容器在 x 点有一些区域，按 z 索引排序。 然后对于每个容器检查其内部的形状是否发生碰撞。
看起来效率不是很高，但是还有其他方法吗？
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I have a board as a canvas with several shapes drawn on it, some of them are triangles, circles, rectangles but all are contained inside their own bound delimited rectangle.
"The circle will be inside a rectangle"
I put two circles A, B on the board where A is over B and has some area colliding.
If I click on A area corresponding to the container box but not the actual A circle shape area I wont select the A circle, however that would stop me from selecting B since my A container overlaps and is over B one.
In an event base framework, the child event will go to the parent not siblings I guess.
So my choice was to do a check for all shape container which have some area at point x ordered by z index. Then for each container check if the shape inside it collide.
It does not seem super efficient but is there any other ways?
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您正在处理它以及它可以处理的事情 - 窗口系统通常遵循 Z 顺序（层）。
无论如何，从长远来看，这会更好，特别是如果您希望能够通过在项目周围绘制选择框来选择多个项目。
有一些算法可以通过将矩形转换为 x 轴和 y 轴上的二维表示来查找矩形是否重叠。 您可以执行相同的操作，然后比较您的点以查看您的点重叠的对象：
检测两个矩形相交的算法？
只需将您的点选择（或矩形选择，如果您绘制边界框来选择多个项目）视为另一个矩形，以与其他矩形重叠进行比较。
-亚当
You're handling it about as well as it can be handled - windowing systems generally obey Z order (layers).
This will be better in the long run anyway, especially if you want to be able to select multiple items by drawing a selection box around them.
There are algorithms for finding if rectangles overlap by converting them into 2d representations on both the x and y axis. You can do the same thing, and then compare your point to see which objects your point overlaps:
Algorithm to detect intersection of two rectangles?
Just treat your point selection (or rectangle selection if you draw a bounding box to select multiple items) as another rectangle to be compared as overlapping to the others.
-Adam
如果您确实需要速度，可以使用一些技巧。 例如：
如果您只是追求简单的实现，一个快速技巧就是记录 X 和 X 值。 Y，重新绘制屏幕，并注意哪个对象绘制了该像素。
——马库斯Q
There are tricks you can play if you really need speed. For example:
If it's just simple implementation you're after, one quick trick is to record the X & Y, repaint the screen, and note which object paints that pixel.
-- MarkusQ