Calculate angle of moving ball after collision with angled or sloped wall that is a 2D line segment

Posted by Ben Mc on Stack Overflow See other posts from Stack Overflow or by Ben Mc
Published on 2010-12-24T00:15:13Z Indexed on 2010/12/24 0:54 UTC
Read the original article Hit count: 242

Filed under:

android

|

game-physics

If you have a "ball" inside a 2D polygon, made up of say, 4 line segments that act as bounding walls, how do you calculate the angle of the ball after the collision with the irregularly sloped wall?

I know how to make the ball bounce if the wall is horizontal, vertical, or at a 45 degree angle. I also have my code setup to detect a collision with the wall.

I've read about dot products and normals, but I cannot figure out how to implement these in Java / Android. I'm completely stumped and feel like I've looked up everything 10 pages deep in Google 10 times now. I'm burned out trying to figure this out, I hope someone can help.

© Stack Overflow or respective owner

Related posts about android

Please verify my layout: bottom button keeps coming up over keyboard

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi everyone, I have a layout which does almost what I want. There's just one bug regarding the button at the bottom. I should stay at the bottom at all times. But whenever I bring up the soft-keyboard the button will be displayed above the keyboard. This is not what I want but it should become covered… >>> More
Android programming. Application stopped unexpectedly.

as seen on Stack Overflow - Search for 'Stack Overflow'
I've just created a prototype of interface for my android app and tried to run it. Unfortunately I get an error that my app has stopped unexpectedly (my reputation doesn't allow me to post images so follow my links): screenshot of error message This is layout mode of editing. Everything looks as… >>> More
Listview Row Overlap Problem

as seen on Stack Overflow - Search for 'Stack Overflow'
I just updated my app and I am getting some odd complaints from people who update it. I am only getting complaints from people with non-stock android phones (phones that manufacturers have modified...HTC phones, cliq, pulse, etc), other phones like the Droid, Nexus work fine. My app (Photo Frame Deluxe)… >>> More
Why are some of my view not aligned correctly at the bottom of my relative layout?

as seen on Stack Overflow - Search for 'Stack Overflow'
I have problems getting some of my views aligned in a relative layout that I use inside a row of my listview. Here is a screenshot from the layout builder in Eclipse, this is what I think it should look like: The next image is from the emulator. Now the TestTestTest View is at the top and covers… >>> More
Android RatingBar weirdness: Whenever I add a RatingBar to my layout, a bunch of the generated tags,

as seen on Stack Overflow - Search for 'Stack Overflow'
Whenever I use a RatingBar view in my layout, I suddenly get all kinds of compile errors. I'm using Android 2.0, but I've also tried 2.0.1, and 2.1, without joy. I also get a message: Shader 'android.graphics.BitmapShader' is not supported in Layout Editor, and an odd warning which may or maynot be… >>> More

Related posts about game-physics

Game physics / 2D Collision detection AS3

as seen on Game Development - Search for 'Game Development'
I know there are some methods you can use like hittestPoint and so on, but I want to see where my movieclip colliedes with another another movieclip. Any other methods I can use? by any chance does somebody know some a good introduction to game physics? Im asking because I coded a small engine and… >>> More
Game Physics With RK4 Implementation For A 2D Platformer

as seen on Game Development - Search for 'Game Development'
I been reading about RK4 for physics implementation in a game, so I read in some pages and all people recommend me this page: http://gafferongames.com/game-physics/fix-your-timestep/ This page shows clearly how this one works, but I can't figure out how to implement in my game, maybe I don't understand… >>> More
How does 2D Game Physics work? [closed]

as seen on Game Development - Search for 'Game Development'
Possible Duplicate: How do I build a 2D physics engine? If we take the game Angry Birds that had big success lately I were thinking how do they implement the physics in a game like that? Your are shooting of your birds and they hit something that will fall off and in turn creating a chain… >>> More
Game Physics: Implementing Normal Reaction from ground correctly

as seen on Game Development - Search for 'Game Development'
I am implementing a simple side scrolling platform game. I am using the following strategy while coding the physics: Gravity constantly acts on the character. When the character is touching the floor, a normal reaction is exerted by the floor. I face the following problem: If the character is… >>> More
Runge-Kutta (RK4) integration for game physics

as seen on Stack Overflow - Search for 'Stack Overflow'
Gaffer on Games has a great article about using RK4 integration for better game physics. The implementation is straightforward but the math behind it confuses me. I understand derivatives and integrals on a conceptual level but I haven't manipulated equations in a long time. Here's the brunt of Gaffer's… >>> More