springweb

README

Web of Springs

A web of point-masses connected by springs is modeled as a graph and physics calculation. Each springs ends accelerates its mass to reach the springs ideal length. The force effected in this way on a springs masses is given by a factor K specific to the spring and the distance between the current positions of the two connected masses.

Create a Web

The web of point-masses are edited by adding a dot and scrolling the mouse-wheel (or clicking an up/down triangle) in order to define its mass. The mass M at a given dot is indicated by the area of the drawn dot. When a dot is added and only at that time it may be connected to the existing dots. In this way the connected dots forms a graph already non-cyclic as created dot by dot, and the web can be passed as-is to the spring-model. When a dot is connected a line is drawn to it, representing a spring. The K factor of the spring is adjusted by the mouse-wheel (or alternatively by the up/down triangles). Clicking a second time on a dot will remove last added either dot or line.

When the web drawn is satisfactory to the observer, the model may be run by clicking the right-pointing triangle on the top left. Clicking anywhere once running will displace the last (the selected) point-mass added. Any other point-mass can be selected by the mouse-wheel (or clicking the arrow triangles). Clicking the upper left double-rectangle (swapped for the triangle to run) will go back to edit-mode so that additional dots and lines may be added, or the existing ones removed or the last objects respective K or M value modified.

http://maraca.name/springweb-create/

Game with Alphabet

A car is controlled by mouse position, affecting with a force to its front or back. To the right is ahead, and letters will appear to collect among the platforms.

http://maraca.name/springweb-game/

Documentation

Index

• Variables
• func Step(nodes []Node, duration float64)
• func StepsPrepare(nodes []Node)
• type Arm
  • func (arm *Arm) Angle() float64
  • func (arm *Arm) Prepare()
• type Node
  • func NewNode(x, y, r, m float64) Node
  • func (node *Node) NewSpring(to *Node, k, a float64)
  • func (node *Node) Prepare()
• type Spring
  • func (s *Spring) Prepare()

Variables

var ArmResist float64 = 1e-3

var SpringResist float64 = 1e-3

Functions

func Step

func Step(nodes []Node, duration float64)

func StepsPrepare

func StepsPrepare(nodes []Node)

Types

type Arm

type Arm struct {
	K, InitAngle, PrevAngle float64
	Rotations               int
	// contains filtered or unexported fields
}

func (*Arm) Angle

func (arm *Arm) Angle() float64

func (*Arm) Prepare

func (arm *Arm) Prepare()

type Node

type Node struct {
	X, Y, R, M           float64
	VelocityX, VelocityY float64
	Angle                float64
	Springs              []Spring
	// contains filtered or unexported fields
}

func NewNode

func NewNode(x, y, r, m float64) Node

func (*Node) NewSpring

func (node *Node) NewSpring(to *Node, k, a float64)

func (*Node) Prepare

func (node *Node) Prepare()

type Spring

type Spring struct {
	To             *Node
	K, Distance    float64
	FromArm, ToArm Arm
	// contains filtered or unexported fields
}

func (*Spring) Prepare

func (s *Spring) Prepare()