Java-Gaming.org Hi !
 Featured games (90) games approved by the League of Dukes Games in Showcase (778) Games in Android Showcase (231) games submitted by our members Games in WIP (856) games currently in development
 News: Read the Java Gaming Resources, or peek at the official Java tutorials
Pages: [1]
 ignore  |  Print
 [SOLVED] Using distance formula for collision detection?  (Read 3337 times) 0 Members and 1 Guest are viewing this topic.
wreed12345

JGO Knight

Medals: 28
Projects: 3
Exp: 5 years

https://github.com/wreed12345

 « Posted 2012-11-27 23:38:09 »

WOuld it be effective to use the distance formula to test for collision detection between two moving images (characters)? or is there some other more efficient method. I figured this wouldnt be too hard to implement

Agro
 « Reply #1 - Posted 2012-11-27 23:42:13 »

Assuming your image is a square, no. You could use the AABB method I guess but if its 2 squares you can do it like this:

 1  2  3  4  5  6  7  8 `public boolean collides(Rect a, Rect b) {    if(a.x < b.x + b.width) return true;    if(a.y < b.y + b.height) return true;    if(a.x + a.width > b.x) return true;    if(a.y + a.height > b.y) return true;    return false;}`

However, if your characters are circles, then yes. You can use the distance formula and check if the distance returned is less than the radius of both circles added together. Then there is a collision.

wreed12345

JGO Knight

Medals: 28
Projects: 3
Exp: 5 years

https://github.com/wreed12345

 « Reply #2 - Posted 2012-11-28 00:05:01 »

Well the game i had in mind was a circle colliding with a square image. What do you think would be best for that?

Agro
 « Reply #3 - Posted 2012-11-28 00:06:15 »

Yeah, use AABB: http://www.java-gaming.org/topics/basic-collision-detection/27326/view.html

He explains it in the best possible way ^_^

wreed12345

JGO Knight

Medals: 28
Projects: 3
Exp: 5 years

https://github.com/wreed12345

 « Reply #4 - Posted 2012-11-28 00:12:51 »

thanks for the help!

theagentd
 « Reply #5 - Posted 2012-11-28 14:15:01 »

Assuming your image is a square, no. You could use the AABB method I guess but if its 2 squares you can do it like this:

 1  2  3  4  5  6  7  8 `public boolean collides(Rect a, Rect b) {    if(a.x < b.x + b.width) return true;    if(a.y < b.y + b.height) return true;    if(a.x + a.width > b.x) return true;    if(a.y + a.height > b.y) return true;    return false;}`

However, if your characters are circles, then yes. You can use the distance formula and check if the distance returned is less than the radius of both circles added together. Then there is a collision.
A circle to circle test isn't expensive either...

 1  2  3  4  5 `public boolean collides(Circle a, Circle b) {    float dx = a.x - b.x, dy = a.y - b.y;    float dist = a.radius + b.radius;    return dx*dx + dy*dy < dist*dist;}`

Myomyomyo.
Pages: [1]
 ignore  |  Print

 hadezbladez (360 views) 2018-11-16 13:46:03 hadezbladez (194 views) 2018-11-16 13:41:33 hadezbladez (363 views) 2018-11-16 13:35:35 hadezbladez (91 views) 2018-11-16 13:32:03 EgonOlsen (2193 views) 2018-06-10 19:43:48 EgonOlsen (2228 views) 2018-06-10 19:43:44 EgonOlsen (1385 views) 2018-06-10 19:43:20 DesertCoockie (2023 views) 2018-05-13 18:23:11 nelsongames (1677 views) 2018-04-24 18:15:36 nelsongames (2313 views) 2018-04-24 18:14:32
 LiquidNitrogen 14x KaiHH 14x Spasi 13x orange451 13x 65K 10x bullen 9x NuclearPixels 9x polinc 7x Zemlaynin 7x VaTTeRGeR 6x gouessej 5x CJC 3x cygnus 3x philfrei 3x SHC 2x princec 2x
 Deployment and Packagingby mudlee2018-08-22 18:09:50Java Gaming Resourcesby gouessej2018-08-22 08:19:41Deployment and Packagingby gouessej2018-08-22 08:04:08Deployment and Packagingby gouessej2018-08-22 08:03:45Deployment and Packagingby philfrei2018-08-20 02:33:38Deployment and Packagingby philfrei2018-08-20 02:29:55Deployment and Packagingby philfrei2018-08-19 23:56:20Deployment and Packagingby philfrei2018-08-19 23:54:46
 java-gaming.org is not responsible for the content posted by its members, including references to external websites, and other references that may or may not have a relation with our primarily gaming and game production oriented community. inquiries and complaints can be sent via email to the info‑account of the company managing the website of java‑gaming.org