Layer Definitions

• query: ModMS query expression
• style: Map styling parameters (min, max, step, fill, colormap, etc.)

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Access Layer Definitions

curl -u crystal:CLandSky http://crystal.arabiaweather.com/layers

• Username: crystal
• Password: CLandSky

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Layer Structure

{
  "name": "GFS 200HPA WIND",
  "query": "speed(GFS.ISO200HPA.UGRD, GFS.ISO200HPA.VGRD) | dir(GFS.ISO200HPA.UGRD, GFS.ISO200HPA.VGRD)",
  "style": {
    "min": 0,
    "max": 100,
    "step": 1,
    "fill": "gradient",
    "contour": false,
    "vector": "vector",
    "colormap": "shakerwind",
    "numgrid": false,
    "linewidth": 2
  }
}

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Layer Components

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Query Field

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Style Field

• min: Minimum value for color scale
• max: Maximum value for color scale
• step: Step size for color bands
• fill: Fill style (gradient, band, none)
• contour: Enable contour lines (true/false)
• vector: Vector overlay style (none, vector, barb, direction)
• colormap: Color scheme name
• numgrid: Show grid point values (true/false)
• linewidth: Contour line width

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Related Documentation

• Map Drawing Guide - How to generate map images from ModMS
• Crystal Overview - Crystal service documentation