C3DL Collision Detection

From CDOT Wiki
Jump to: navigation, search

Name of Project

Canvas 3D - Collision Detection

Description

The ability to detect any object(s) colliding with object(s).

Blog: http://www.c3dl.org/index.php/development-news/

Project Demo Pages: http://matrix.senecac.on.ca/~pplam3/

Leader(s)

Project Contributor(s)

  • Catherine Leung
  • Andor Salga

Contribution(s)

Student Demo

  • Jan 27th (Week 3) - 10:00am
  • Feb 26th (Week 7) - 10:00am
  • Mar 31st (Week 11) - 10:00am

Releases

0.4 - Week of Jan 19

  • Created flag for models to have collision detection
    • Created set/get functions for flag
  • Created function for bounding sphere for models
    • Returns array of 2: Sphere Position (array of 3), Sphere Radius (float)
  • Enable callback to check for collision detection when updating scene

0.5 - Week of Feb 2

  • Performed initial test for collision
    • Check flags
    • Check for bounding sphere collision with out models with flags on
      • Collision - distance of two bounding sphere's position is less than the sum of the radius of both sphere
  • Perform 2nd test for collision
    • Test for triangle-triangle intersection test between objects

0.6 - Week of Feb 16

  • Create a function which returns the object’s next position: getNextPosition(timeSpan)
  • Create a function which returns the bounding volume of the object
    • think of it as a stretched bounding sphere which encloses the objects current position and it’s future position
  • Break down the updates into smaller test, so it doesn’t skip any collisions in between the updates
  • Extract the collision detection test out from the scene class, and write it as a class of its own

0.7 - Week of Mar 9

  • Improve Efficiency

0.8 - Week of Mar 23

  • Improved Efficiency
  • Added optional flag to turn on triangle-triangle testing
    • Default with only bounding-sphere test, triangle-triangle test off
  • Added function for
    • Setting how many sections/areas/quadrants to break the 3D space into (in multiples of 4)
    • Get the objects in a specific section/area/quadrant

0.9 - Week of Apr 6

  • Sectioning
  • Stepping

1.0 - Week of Apr 20

Project Updates

April 2009

Apr 24, 2009

  • Finished 2 more demo

Apr 23, 2009

Apr 12, 2009

  • Implemented "stepping"
    • Functions with changes in CollisionDetection.js:
      • objInSection
      • boundingSphereTest
      • tri_tri_test

Apr 10, 2009

Apr 5, 2009

March 2009

Mar 29, 2009

  • Added function for
    • Setting how many sections/areas/quadrants to break the 3D space into (in multiples of 4)
    • Get the objects in a specific section/area/quadrant

Mar 26, 2009

  • Added a switch for turning on/off triangle test
    • By default, only using bounding sphere test, the triangle test is off

Mar 25, 2009

  • Further narrowed down the number of triangles tested for collision
    • Only triangles from Object A with vertices inside the bounding sphere of Object B and vice versa

Mar 11, 2009

  • Improved efficiency
    • Only perform triangle checks with triangles on the front side (cuts the number of triangle test by about half)

Mar 6, 2009

  • Made demo explaining need for 'stepping'

Mar 4, 2009

  • Changed return type of CollisionDetection
    • returns an array of 2 objects
    • each item in the array holds 1) the object tested for collision 2) the list of index to the objects it collides with

February 2009

Feb 24, 2009

  • Changed the getBoundingVolumn()
    • returns same data type as getBoundingSphere()
    • [center, radius]

Feb 20, 2009

  • Create a function which returns the bounding volume of the object
    • think of it as a stretched bounding sphere which encloses the objects current position and it’s future position
  • Break down the updates into smaller test, so it doesn’t skip any collisions in between the updates

Feb 18, 2009

  • Extracted collision detection code from scene object
    • Created a new class for collision detection
  • Successful in adding collision detection into scene update callback on user side
    • Users can easily add collision detection functionality whenever they want and get the result back from it as scene is updated

Feb 13, 2009

  • Created a 2nd demo page which includes triangle-triangle test
    • Explain the difference between having it and not having it

Feb 12, 2009

  • C3DL meeting
    • extract the code for collision detection out of scene class and create a class of it's own
  • Working on breaking down the updates into smaller steps
    • There was a major lag in performance, need to further investigate on what's the main cause of slow down

Feb 8, 2009

  • created getNextPosition(timeStep) function
    • returns the position of the object after timeStep - ie. get the object's future position

Feb 4, 2009

  • Dropped Tomas Moller's algorithm
  • Reapplied the idea of using line-triangle intersection test from picking
    • Made two important change to get it working
      • performed a check on the variable t to make sure it's between 0-1 (the length of the edges of triangle A)
      • set the accuracy to 0.02 instead of 0.8

Feb 3, 2009

  • Implemented Tomas Moller's Triangle-Triangle Intersection Test algorithm
    • Did not work, might have bugs in the implementation
    • Causes extreme slowdown when objects with more faces exist (ie. sphere)

Feb 1, 2009

  • Triangle-Triangle test failed using Ray-Triangle test
    • Reading/Looking for other ways of doing Triangle-Triangle test

January 2009

Jan 31, 2009

  • Reused code from picking function for triangle-triangle intersection test
    • Using the 3 edges of Triangle A as lines and perform Line-Triangle intersection test

Jan 28, 2009

Jan 25, 2009

  • Started on Triangle-Triangle Test function

Jan 17, 2009

  • Perform initial test for bounding sphere collision

Jan 16, 2009

  • Created bounding sphere for models

Jan 15, 2009

  • Enable callback to collision detection function
  • Created flags for collision detections
    • Set/Get functions

Jan 13, 2009

  • Created wiki page
Retrieved from "https://wiki.cdot.senecapolytechnic.ca/w/index.php?title=C3DL_Collision_Detection&oldid=95286"