Dynamic Simplification IV

100%

Dynamic Simplification IV

✓ Published0🌍 Public

Last edited Nov 20, 2016

Created on Dec 2, 2013

This map of U.S. states shows dynamically simplified geometry that adjusts its level of detail based on zoom, keeping the smallest visible feature roughly one pixel in size. The example uses TopoJSON data with `topojson.presimplify` and a custom `d3.geoTransform` filter based on a minimum area threshold, applied through `d3.geoPath` with Canvas rendering. Zooming is handled by `d3.zoom`, which updates the simplification threshold and redraws filled land polygons and state borders on the canvas.

AI-generated description

This map dynamically simplifies the geometry in response to zooming, so that the smallest displayed detail is approximately one square pixel. Use the mousewheel, or pinch on touch devices, to zoom.

gpl-3.0 Licensed

Similar vizzes

Loading thumbnail…

Dynamic Simplification II

This example combines map zooming with dynamic simplification. As the map zooms in and out, the simplification area threshold adjusts based on the current scale, keeping the map visually clear and rendering quickly. Points outside the viewport are simplified much more heavily than those inside, approximating viewport clipping. The code uses `d3.geo.transform` to filter points, `d3.behavior.zoom` for interaction, and `d3.geo.path` with a Canvas context to draw the TopoJSON data (us-states.json), animating between zoom levels with `transition`.

Mmbostock

91% match

Loading thumbnail…

Dynamic Simplification IV zoom to bounding box

This map of U.S. states dynamically simplifies geometry during zooming so that visible detail stays near one square pixel, using D3 v4 and topojson-simplify. Clicking any state highlights it and triggers a smooth zoom to its bounding box via `d3.zoom` and `d3.geoPath`. A hidden canvas with `getImageData` identifies the selected feature by color, while borders and fills render on a visible Canvas with animation.

CCyberZafa

91% match

Loading thumbnail…

Dynamic Simplification

This example shows a map of the United States that continuously simplifies its boundaries, alternating between depicting all counties and reducing them to a coarse outline. The animation cycles through progressive shapes while preserving topology. The code uses `topojson.presimplify` to precompute point importance, a custom `d3.geo.transform` geometry stream to filter points based on a dynamic area threshold, and `d3.geo.path` to render the result onto a Canvas via its 2D context, driven by `transition.tween` and `d3.interpolate`.

Mmbostock

89% match

Loading thumbnail…

Dynamic Simplification III

This example demonstrates dynamic simplification of a filled polygon representing US land masses, where the level of detail adapts during zooming. The effect is subtle because the polygon fill hides most topological changes. Animated transitions repeatedly zoom between a close-up of the Chesapeake Bay and a full view of the country. The visualization uses d3.geo.path with a custom d3.geo.transform to filter points based on an area threshold, rendered on a Canvas via the context API, with d3.behavior.zoom and TopoJSON data.

Mmbostock

87% match

Loading thumbnail…

Map Zooming II

Moving the mouse across the map smoothly interpolates a zoom between San Francisco and New York. The visualization renders United States state boundaries as a canvas-drawn mesh using d3.geo.path with a custom projection that applies dynamic simplification and clipping during the zoom. It uses d3.interpolateZoom, d3.geo.transform, and d3.geo.clipExtent to control the transition, adjusting the scale and translate values based on the pointer's horizontal position. The underlying TopoJSON data is pre-simplified with topojson.presimplify, and the rendering occurs entirely through the Canvas 2D API.

Mmbostock

80% match

Loading thumbnail…

Map Zooming III

A map of the United States is drawn with canvas, and moving the mouse horizontally smoothly interpolates between three zoom levels centered on San Francisco, New Orleans, and New York. The example uses a linear scale with `d3.interpolateZoom` to map mouse position to a zooming transform, and `d3.geo.transform` for simplification. It renders TopoJSON state boundaries clipped by `d3.geo.clipExtent`, using D3 v3’s `d3.geo.path` with a canvas context.

Mmbostock

80% match

Loading thumbnail…

Line Simplification

This example demonstrates line simplification, a technique that reduces the complexity of geographic shapes by removing points based on their calculated area. Using a United States land mass dataset loaded via TopoJSON, it animates the transition between high and low simplification thresholds, cycling the minimum area from 0.1 to 100 square pixels and back. The visualization uses d3.simplify, a custom algorithm that employs a min-heap to prioritize point removal by triangle area, and renders the results with d3.geo.path and SVG. A text label displays the current threshold and the percentage of points retained.

Mmbostock

79% match

Loading thumbnail…

Zoomable Geography

This example shows U.S. states and counties rendered as SVG paths, which can be panned and zoomed with the mouse. It uses d3.behavior.zoom to modify the transform of a group element, letting the browser redraw geographic features quickly without reprojection. The code loads TopoJSON data and renders it with d3.geo.path, using a null projection to preserve the pre-computed geometry. Border stroke widths are adjusted inversely to the zoom scale to maintain a constant visual weight.

Mmbostock

78% match