Spatial DECM

Spatial-D.E.C.M

(V2)

Layers

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CartoDB Dark Matter Ready for spatial uploads.

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Base map

Map Tools

LAT —

LNG —

Attribute Table

No editable layer selected.

Peaks & Hills

Elevation Source

Area of Interest

Uses the current visible map area for local DEM analysis.

Radius (meters)

Summit Detection

Search radius (px) Minimum relief (m)

Smoothing (px) Peak cutoff (m)

Relief is measured against nearby lower terrain. Results above the peak cutoff are labelled Peak; the rest are labelled Hill.

Minimum elevation (m) Max results

Running…

Viewshed / Diffraction Loss Modelling

Max Radius (0 = unlimited)

m

Observer Height

m

Target Height

m

Apply earth curvature correction

Observer Source

Multiple Knife-Edge Diffraction

Computes received signal strength from terrain diffraction using the Epstein-Peterson method. Output is a red opacity raster named KED Diffraction Loss.

Frequency (MHz)

MHz

Tx Power (dBm)

dBm

Rx Threshold (dBm)

dBm

Ray Samples

Observer Location

Point Vector Layer Radius Field (optional) Observer Height Field (optional) Common Observer Height

m

Common Radius

m

Each observer creates separate viewshed polygon features and a separate view point feature in the output layer.

Computing viewshed…

Watershed

Elevation Source

Fetch radius 10 km

Area of Interest

Not drawn

Analyses the entire visible area. Pan & zoom to region first, then run.

Channel Threshold cells

Min Slope (flat areas) 0.0001 m/m

Wang & Liu fill: minimum gradient imposed across flat sinks. Lower values preserve flat areas; higher values force stronger drainage.

Sub-basins

Computing…

Export Layer

Choose a file name and format for export.

File name Format

Add Layer

Browse for a spatial file or create a new empty layer with your own name.

New layer name Geometry type

Add Field

Add a new attribute field to every feature in the layer currently in edit mode.

Field name Default value

Field Calculator

New field Update field

Output field name Field to update

Click a variable to insert it at the cursor.

Preview on

Write an expression above to see a live preview.

Saved expressions

Styling & Labeling

Configure vector symbols, rule-based styling, and labels.

Mode Attribute Field

Color Stroke color Stroke width Shape Size

Stroke color Stroke width

Stroke color Stroke width

Color ramp Classification Classes

Features matching the rule use the rule color; others use the base style.

Field Operator Value Rule color

Stroke color Stroke width

Labels

Enable labels

Label Source

Label field Expression / template

Font

Font family Font size Text color

Text opacity 100%

Style Bold Italic Underline

Halo & Background

Halo color Halo size

Background color

None

Border color

None

Border radius

px

Effects Drop shadow

Placement

Point placement Line placement Polygon placement

Offset (px)

X

Y

Rotation

°

Visible zoom (0 – 22)

Min

Max

Priority Collision Avoid overlap

Point Interpolation

Build an interpolated surface from numeric point attributes.

Value field Method Sample scope Clip extent Influence radius (meters) Cell size (meters) Power Opacity Minimum nearby samples Color ramp

Raster Symbology

Style the active raster layer and inspect its source metadata.

Render type Band Color ramp Classification Classes Minimum Maximum NoData value Brightness Contrast Opacity

Metadata

Point Heatmap

Build a raster heatmap from point density or weighted values.

Weight field Sample scope Clip extent Radius (meters) Cell size (meters) Opacity Minimum nearby samples Intensity exponent Exact cell size Bypass auto-resize (may cause performance issues for large areas) Color ramp

Layer Filter

Build rules to control which features remain visible.

Match rules with

Instructions

Data

Map Tools

Export

Drop files anywhere to import Supported: GeoJSON, KML, GPX, zipped or loose shapefiles, CSV, GeoTIFF