simplify-geometry

Simplify complex geometries using the Douglas-Peucker algorithm, reducing vertices while preserving shape. Specify WKT geometry and tolerance for spatial data optimization.

Instructions

Geometriyi basitleştir (Douglas-Peucker algoritması)

Input Schema

TableJSON Schema

Name	Required	Description
`geometry_wkt`	Yes	WKT formatında geometri
`preserve_collapsed`	No	Çöken geometrileri koru
`tolerance`	Yes	Basitleştirme toleransı

Implementation Reference

server.ts:1567-1620 (handler)

Handler for the 'simplify-geometry' tool. Parses input using SimplifyGeometrySchema, determines simplify function (ST_Simplify or ST_SimplifyPreserveTopology), executes PostGIS query to simplify geometry, computes metrics like point count and area before/after, and returns detailed JSON response including reduction ratio.

case "simplify-geometry": {
  const { geometry_wkt, tolerance, preserve_collapsed } =
    SimplifyGeometrySchema.parse(args);

  const simplifyFunc = preserve_collapsed
    ? "ST_SimplifyPreserveTopology"
    : "ST_Simplify";

  const result = await client.query(
    `
    SELECT 
      ST_AsText(${simplifyFunc}(ST_GeomFromText($1), $2)) as simplified_wkt,
      ST_AsGeoJSON(${simplifyFunc}(ST_GeomFromText($1), $2)) as simplified_geojson,
      ST_NumPoints(ST_GeomFromText($1)) as original_points,
      ST_NumPoints(${simplifyFunc}(ST_GeomFromText($1), $2)) as simplified_points,
      ST_Area(ST_GeomFromText($1)::geography) as original_area,
      ST_Area(${simplifyFunc}(ST_GeomFromText($1), $2)::geography) as simplified_area
  `,
    [geometry_wkt, tolerance]
  );

  return {
    content: [
      {
        type: "text",
        text: JSON.stringify(
          {
            input_geometry: geometry_wkt,
            tolerance: tolerance,
            preserve_collapsed: preserve_collapsed,
            simplified_wkt: result.rows[0].simplified_wkt,
            simplified_geojson: JSON.parse(
              result.rows[0].simplified_geojson
            ),
            original_points: result.rows[0].original_points,
            simplified_points: result.rows[0].simplified_points,
            original_area_sqmeters:
              parseFloat(result.rows[0].original_area) || 0,
            simplified_area_sqmeters:
              parseFloat(result.rows[0].simplified_area) || 0,
            reduction_ratio:
              result.rows[0].original_points > 0
                ? 1 -
                  result.rows[0].simplified_points /
                    result.rows[0].original_points
                : 0,
          },
          null,
          2
        ),
      },
    ],
  };
}

server.ts:88-92 (schema)
Zod input schema for 'simplify-geometry' tool validating geometry_wkt (string), tolerance (number), and optional preserve_collapsed (boolean). Used for parsing arguments in the handler.
```
const SimplifyGeometrySchema = z.object({
  geometry_wkt: z.string(),
  tolerance: z.number(),
  preserve_collapsed: z.boolean().optional().default(false),
});
```

server.ts:752-772 (registration)

Tool registration in ListToolsRequestHandler, defining name, description, and JSON inputSchema matching the Zod schema for client tool listing.

  name: "simplify-geometry",
  description: "Geometriyi basitleştir (Douglas-Peucker algoritması)",
  inputSchema: {
    type: "object",
    properties: {
      geometry_wkt: {
        type: "string",
        description: "WKT formatında geometri",
      },
      tolerance: {
        type: "number",
        description: "Basitleştirme toleransı",
      },
      preserve_collapsed: {
        type: "boolean",
        description: "Çöken geometrileri koru",
      },
    },
    required: ["geometry_wkt", "tolerance"],
  },
},

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