Solved

Line intersects rectangle?

Posted on 2009-04-03
6
268 Views
Last Modified: 2012-05-06
Hi,

How can I test if a line (defined by two x,y endpoints) intersects a rectangle?

I have a bunch of rectangles draw on a screen, and want to know if a user's mouse intersects any of them when they move the mouse. I only get mouse move messages every so often, so if the user moves the mouse fast enough, most of the mouse location points are missed. So I'm looking to figure out which rectangles could have been intersected between two mouse points.

Thanks
0
Comment
Question by:DJ_AM_Juicebox
  • 3
  • 3
6 Comments
 
LVL 84

Accepted Solution

by:
ozo earned 250 total points
ID: 24065536
0
 
LVL 31

Assisted Solution

by:GwynforWeb
GwynforWeb earned 250 total points
ID: 24065595
0
 
LVL 84

Expert Comment

by:ozo
ID: 24065652
http://www.siggraph.org/education/materials/HyperGraph/scanline/clipping/cliplb.htm
says that Liang-Barsky is a 36% speed improvement over  Cohen -Sutherland for 2D lines
0
Courses: Start Training Online With Pros, Today

Brush up on the basics or master the advanced techniques required to earn essential industry certifications, with Courses. Enroll in a course and start learning today. Training topics range from Android App Dev to the Xen Virtualization Platform.

 
LVL 31

Expert Comment

by:GwynforWeb
ID: 24065826
...the questioner is not clipping,  just detecting incidence with the rectangular.
0
 
LVL 84

Expert Comment

by:ozo
ID: 24066020
that's what line clipping algorithms do
0
 
LVL 31

Expert Comment

by:GwynforWeb
ID: 24066221
...line clipping gives the clipped line segment. That is different than just detecting if the line crosses the rectangle.
0

Featured Post

Live: Real-Time Solutions, Start Here

Receive instant 1:1 support from technology experts, using our real-time conversation and whiteboard interface. Your first 5 minutes are always free.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
Two list de-cypher 6 95
Compound interest rate 3 60
Dice Roll Probabilities 3 97
China bladeless fan : comment on quality & blowing strength & noise level 4 78
Foreword (May 2015) This web page has appeared at Google.  It's definitely worth considering! https://www.google.com/about/careers/students/guide-to-technical-development.html How to Know You are Making a Difference at EE In August, 2013, one …
Lithium-ion batteries area cornerstone of today's portable electronic devices, and even though they are relied upon heavily, their chemistry and origin are not of common knowledge. This article is about a device on which every smartphone, laptop, an…
This is a video describing the growing solar energy use in Utah. This is a topic that greatly interests me and so I decided to produce a video about it.
Although Jacob Bernoulli (1654-1705) has been credited as the creator of "Binomial Distribution Table", Gottfried Leibniz (1646-1716) did his dissertation on the subject in 1666; Leibniz you may recall is the co-inventor of "Calculus" and beat Isaac…

813 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

19 Experts available now in Live!

Get 1:1 Help Now