drawing_borders = (svg, g) => {
if (border) svg.attr('style', 'border: 1px solid salmon');
if (border) g.append('rect')
.attr('id', 'drawing-border')
.attr('width', dim.gW).attr('height', dim.gH)
.attr('fill', 'none').attr('stroke', 'black').attr('stroke-dasharray', '10 10');
}