intersection of two triangles

2014 4 3
2 个回答
回答已采纳
更新时间：2020 8 21
3 次查看（30 天）

1 个投票

Hi,
I have 2 triangles and I would like to know if they are inside each others or they intersect. Like the picture How I can do that ? I read about polyxpoly but to be honest I don't understand how to use it in this scenario.

请先登录，再回答此问题。

 采纳的回答

Marta Salas
Marta Salas 2014-4-3

3 个投票

% this define the vertexes (x,y) of first triangle
trian1x =[ 0 0.5 1 0];
trian1y =[ 0 1 0 0];
% this define the vertexes (x,y) of second triangle
trian2x =[ 0 0.25 0.5 0];
trian2y =[ 0 0.5 0 0];
% (xi,yi) are the intersection points
[xi,yi] = polyxpoly(trian1x,trian1y,trian2x,trian2y,'unique');
figure,
plot(trian1x,trian1y,'b')
hold on
plot(trian2x,trian2y,'r')
hold on
plot(xi,yi,'*g')

5 个评论
显示 3更早的评论 隐藏 3更早的评论

Sososasa
Sososasa 2014-4-3
编辑：Sososasa 2014-4-3
Hi Marta,
This gives me the intersection points even when one triangle is lie inside the other. And I only need to get the intersection points if one of them is not contained inside the other.
If I get the intersection point in both situations, then I can not decide if one of them is actually inside the other or not.
Marta Salas
Marta Salas 2014-4-3
编辑：Marta Salas 2014-4-3
You can decide whether it's inside or not checking if the intersection points correspond to the triangle vertexes.
Sososasa
Sososasa 2014-4-4
Yap I did that thanks a lot :)
Ines
Ines 2016-4-19
Hi If I have the vertexes of two triangles, how can I check if they intersect or not? I need a function that just gives me true if they intersect and false if not. Thanks
Yash Jangir
Yash Jangir 2020-8-21
what if there are no intersection points but the triangle is completely inside the other triangle?

请先登录，再进行评论。

更多回答（1 个）

Rushabh Khattri
Rushabh Khattri 2017-8-22

0 个投票

I am getting this error :- Undefined function 'polyxpoly' for input arguments of type 'double'.

2 个评论
显示 无 隐藏 无

Jan
Jan 2017-8-22
The first point to start is asking an internet search engine for this term: "Matlab polyxpoly". You will find out, that this command belongs to the Mapping Toolbox: https://www.mathworks.com/help/map/ref/polyxpoly.html. It seems like you do not have a license for this toolbox and then you need a different solution. Please open a new thread then.
John D'Errico
John D'Errico 2017-8-22
This is not an answer. It is only a new question, but resurrecting a zombie question, that is only partially related.

请先登录，再进行评论。

类别

在 帮助中心 和 File Exchange 中查找有关 Triangulation Representation 的更多信息

产品

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by