Function drawPaths

terrain.js:717–726

(svg, cls, paths)

}

function drawPaths(svg, cls, paths) {
    var paths = svg.selectAll('path.' + cls).data(paths)
    paths.enter()
            .append('path')
            .classed(cls, true)
    paths.exit()
            .remove();
    svg.selectAll('path.' + cls)
        .attr('d', makeD3Path);
}

function visualizeSlopes(svg, render) {
    var h = render.h;