js-2dmath

Fast 2d geometry math: Vector2, Rectangle, Circle, Matrix2x3 (2D transformation), Circle, BoundingBox, Line2, Segment2, Intersections, Distances, Transitions (animation/tween), Noise, Random numbers.

So the objective is "Be fast"

Help needed / TODO LIST

• API completeness
• Testing
• Use falafel/esprima to create an asm.js build
• More Numerical integrators
• AI: Path-finding, Steer, Backtracking
• IK: FABRIK
• Minkowski distance, euclidean, Manhattan
• Beizer math
• Serialization / De-serialization
• did I miss anything useful?

Performance

Performance is based on good practices.

• Avoid new
• Use arrays instead of objects, this is huge performance boost!
• Avoid creating unnecessary variables (reuse intermediate variables) only create & clone methods should create new variables.
• Cache every function call to a single variable. example: Vec2.add => vec2_add, even Math.*
• If access a multi-dimensional array in a loop, cache the array access. for(i...) carr=arr[i]; carr[X]
• Do not use forEach, map, every etc. or other looping method that require apply/call usage, both are costly.

See some performance test that prove it.

funlinify It's a library that do function inline expansion for javascript. It's in early stage but it works perfectly for our usage here.

Obviously I ignore myself in some parts of this library. Feel free to issue me :)

Grunt

npm install -g grunt
npm install -g grunt-cli

grunt dist

Create distribution packages using browserify and documentation.

• debug: debug/js-2dmath-browser-debug.js

  • argumentify Assert on invalid arguments to properly debug your app.

• dist: dist/js-2dmath-browser.js

  • funlinify inline function

• dist.min: js-2dmath-browser.min.js

  • funlinify inline function
  • uglify

grunt watch

Watch every change and rebuild the distribution code.

What can you do with js-2dmath?

See some examples.

• Angles
• Beizer
• Circle
• Intersections
• line2
• Matrix23
• Segment2
• Transitions
• Triangle
• Vec2 collisions
• Vec2

API

The documentation is autogenerated with falafel see dist.js for more fun! :)

• Vec2
• Line2
• Segment2
• Rectangle
• AABB2
• Circle
• Matrix22
• Matrix23
• Polygon
• Beizer
• Triangle
• Intersection
• Distance
• Transitions
• Xorshift
• Noise
• Collision.SAT
• Collision.GJK
• Collision.Resolve
• Collision.Manifold

FAQ

How do i know a variable type?

You can't, there is no instanceof or anything like that, everything are numbers/arrays.

I choose to keep track of all types using meaningful naming or enclose the variable in an object like

var movable = {
    body: Polygon.create(/*...*/), // could be a circle, change the type...
    type: "polygon"
}