CompassRose

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Note  The canvas.draw was merged into FGDATA in 03/2020. You can test, improve and play around with it by downloading the CanvasDrawDev add-on.

Introduction

Please have a look at Canvas draw library first.

CompassRose

draw()

draw(cgroup, radius, style=nil);

Draws a compass rose with given radius on an existing canvas group element given as cgroup. Marks and text labels are drawn as defined in style. A default style will be used if style is not given.

Style

The style class for CompassRose, derived from canvas.draw.marksStyle.

new()

return a new style hash

var myStyle = canvas.CompassRose.Style.new();

setMarkCount(value)

value number of marks on compass rose, default: 36

setLabelCount(value)

value number of text labels on compass rose to generate from course degrees, default: 12

setLabelDivisor(value)

value divide course degrees by this value to create text label, default: 10

setFontSize(value)

value fontsize for labels

Note  This should be changed to scale with the radius parameter of the draw function.

Examples

Compass rose HSI style and ND style
Compass example with eight marks.
    # compass test
    var style_HSI = canvas.CompassRose.Style.new();
    style_HSI.setMarkLength(0.1)
        .setMarkOffset(-1)
        .setSubdivisions(1)
        .setSubdivisionLength(0.5);

    var style_NAV = canvas.CompassRose.Style.new();
    style_NAV.set("circle_width", 2)
        .setMarkOffset(1);
    
    var style_3 = canvas.CompassRose.Style.new();
    style_3.setMarkCount(8)
        .setLabelCount(8)
        .setLabelDivisor(1)
        .set("nesw", 0); # No label N,E,S,W instead of 0, 90, 180, 270 degree
        
    var compass1 = myRoot.createChild("group", "compass1");
    var compass2 = myRoot.createChild("group", "compass2");
    var compass3 = myRoot.createChild("group", "compass3");
    canvas.CompassRose.draw(compass1, 100, style_HSI).setTranslation(150, 250);
    canvas.CompassRose.draw(compass2, 140, style_NAV).setTranslation(150, 250);
    canvas.CompassRose.draw(compass3, 210, style_3).setTranslation(...);