Circle Dragging I

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Circle Dragging I

✓ Published0🌍 Public

Last edited Jul 5, 2019

Created on May 11, 2016

This example shows a set of colored circles scattered across an SVG canvas, which users can drag with the mouse. Each circle’s position is stored as x and y properties in its data object, and those values update live during the drag. The code uses d3.select and d3.drag from the d3-drag module to handle the interaction, attaching event handlers for start, drag, and end. At drag start, the circle is raised to the foreground with `.raise()` and gets a black stroke via the `.active` class; the stroke is removed on release. The circles are rendered as SVG `<circle>` elements, colored with a categorical scheme from `d3.scaleOrdinal` and `d3.schemeCategory20`, with random initial positions computed from the SVG’s dimensions.

AI-generated description

This example demonstrates applying d3.drag for dragging circles in SVG. Each circle’s datum is an object with x and y properties. The data and the circle element’s position are updated during the drag event. The circle is raised to the foreground at the start of a drag, and a temporary stroke is applied during drag for visual feedback.

Compare this to dragging Canvas circles. Selection can be improved using a Voronoi overlay.

gpl-3.0 Licensed

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