Geometric constructions with JessieScript

From JSXGraph Wiki
Jump to: navigation, search

Easy JSXGraph constructions with geometric elements can be created by a mathematical syntax by using the function

board.construct(...);

Possible elements:

Construction Description
A(1,1) Point with name 'A' at position (1,1)
ZY(0.5|1) Point with name 'ZY' at position (0.5,1)
]AB[ straight line through points A and B
[AB[ ray through points A and B, stopping at A
]AB] ray through points A and B, stopping at B
[AB] segment through points A and B
g=[AB] segment through points A and B, named by 'g'
k(A,1) circle with midpoint A and radius 1
k(A,B) circle with midpoint A through point B on the circle line
k(A,[BC]) circle with midpoint A and radius defined by the length of the (not necessarily existing) segement [BC]
k_1=k(A,1) circle with midpoint A and radius 1, named by 'k_1'

The different elements have to be separated by semicolon.

The function returns an object with all the created elements so that afterwards properties can be set. The access works by

Element Description
constr.points[i] take i-th point of the construction 'constr'
constr.lines[i] take i-th line (or rays or segement) of the construction 'constr'
constr.circles[i] take i-th circle of the construction 'constr'
constr.A take element with name 'A' of the construction 'constr'

Example

The JavaScript code

var board, cons1, cons2;
board = JXG.JSXGraph.initBoard('box', {grid:true, boundingbox: [-1, 6, 11, -3], axis:true});
        
cons1 = board.construct("A(1,1);B(2,2.5);C(1,3);G(5,3);H(6,4);[GH];k(G,1);AB(5,-1);X(6,-1);Y(7,-2);k(Y,X);k(A,[BC]);k(B,[AC]);");
cons2 = board.construct("J(7,4);[GJ[;K(8,4);]GK[;L(2.4|5);f=[AC];k1=k(C,0.5);C_1(4|4);l_2=[BC]");
        
cons1.points[0].setProperty({face:'diamond',size:7,strokeColor:'#8B2252',fillColor:'#8B2252'});
cons1.circles[1].setProperty({strokeColor:'#BA55D3'});
cons2.J.setProperty({face:'triangleUp',size:8,strokeColor:'black',fillColor:'#EE82EE'});
cons2.lines[1].setProperty({strokeColor:'#32CD32',shadow:true});
        
cons1.X.strokeColor('black');
cons1.X.fillColor('#FFB90F');
cons1.X.shadow(true);
cons1.Y.visible(false);
cons2.l_2.strokeWidth(4);
cons1.X.face('>');
cons1.X.size(8);
cons1.X.labelColor('#FFB90F');
cons2.k1.dash(2);