Need glider to move with point!

[solo...@gmail.com]

Hello, I need help figuring out how to move the glider point based on the Point A X position..

The code I have is:

var board = JXG.JSXGraph.initBoard('box', 

{

boundingbox: [0, 1000, .3, -30], //change bounding box [left, top, right, bottom]

axis:true,

});

var p = [];

var p1 = board.create('point', [-1.0, 0.0], {fixed: true});

var p2 = board.create('point', [0.4, 0.0], {fixed: true});

var l1 = board.create('line', [p1, p2], {fixed: true, highlight: false, strokeColor: '#000000'});

var glider = board.create('glider', [0, 0, l1], {snapToGrid: true, snapSizeX: .01, snapSizeY: .01, name: 'glider'});

var p3 = board.create('point', [.1, 250.0], {snapToGrid: true, snapSizeX: .01, snapSizeY: 10, name: 'Point A'});

var l2 = board.create('line', [glider, p3]);

var perp1 = board.create('perpendicular', [l1, p3], {highlight: false});

//////////////

so what I need is that when I move Point A either to the left or right... I need the glider to move the same amount.

thank you for your help.

M

[Joe Simons]

One way to do this is by using the drag event handler.

See this example:

http://jsfiddle.net/BBAZQ/1/ 

in which the y coordinate of glider 'a' depends on glider 'b'

[Michael]

On Tue, Sep 11, 2012 at 9:54 PM, Joe Simons <mrjoe...@gmail.com> wrote:

One way to do this is by using the drag event handler.

See this example:

http://jsfiddle.net/BBAZQ/1/ 

in which the y coordinate of glider 'a' depends on glider 'b'

That's  an excellent solution if you want to be able to move the glider. If the glider should be fixed, the perpendicular point element (an orthogonal projection of a point onto a line) would be easier to use.

[solo...@gmail.com]

Thank you Joe and Michael,

Your suggestion looks good.

But before you replied, i had achieved what I needed using the code below. Thanks for the help tho.

And lots of Thanks to the JSXGraph team, for developing such a wonderful piece of software!

var board = JXG.JSXGraph.initBoard('box', 

{

boundingbox: [0, 700, .3, -20],

grid: false,

axis: false,

keepaspectratio: false,

});

var p = [];

// Line1 in the X coordinate

var p1 = board.create('point', [-1.0, 0.0], {fixed: true});

var p2 = board.create('point', [0.4, 0.0], {fixed: true});

var l1 = board.create('line', [p1, p2], {fixed: true, highlight: false, strokeColor: '#000000'});

// Point B...glider that glides on Line1

var glider = board.create('glider', [0, 0, l1], {name: 'Point B', snapToGrid: true, snapSizeX: .001});

//Point A, used to control slope of Line 2

var p4 = board.create('point', [.2, 250], {name: 'Point A'});

//Line 2, connects point A and B

var l2 = board.create('line', [glider, p4]);

//This translates Point C, depends on Point A

translateTrans = board.create('transform',[0.1,0],  {type:'translate'});

//Point C, used to move the perpendicular line

var p3 = board.create('point', [glider, translateTrans], {visible: true});

//Creates a perpendicular to Line1

var perp1 = board.create('perpendicular', [l1, p3], {highlight: false, strokeWidth: 1});

//Creates the Intersection point X

var inter = board.create('intersection',[perp1,l2,0],{face: 'x', name: '', size: 8});