d3.js - D3 translation relative to rotation -

does d3 have built in way translate object location relative rotation?

for example, have rectangle that's 50x50, located @ coordinates (100, 100). rectangle rotated 45 degrees. want move 100 units "forward".

i can trig hand figure out, in fiddle: http://jsfiddle.net/qh9x5/6530/

function toradians (angle) {   return angle * (math.pi / 180); }  var svg = d3.select("body").append("svg")     .attr("width", 500)     .attr("height", 500)     .append("g");    svg.append('rect').attr('width', 50).attr('height', 50).attr('fill', 'blue')     .attr('transform', "translate(100, 100) rotate(45)");  var h = 100; var angle = 45; var o = math.sin(toradians(angle)) * h; var = math.cos(toradians(angle)) * h console.log(o)   svg.append('rect').attr('width', 50).attr('height', 50).attr('fill', 'red')     .attr('transform', "translate(100, 100) rotate(45)")     .transition().duration(1000)     .attr('transform', "translate(" + (h + o) + ", " + (h + a)  +") rotate(45)"); 

however seems common use case. before start writing libraries handle calculations i'd need, d3 support through native function, or through popular , maintained addon?

no, d3 doesn't have explicitly this. however, can nesting multiple elements, no need trigonometry:

var g = svg.append("g").attr("transform", "translate(100,100)"); g.append('rect').attr('width', 50).attr('height', 50).attr('fill', 'red')   .attr('transform', "rotate(45)"); g.transition().duration(1000)   .attr('transform', "translate(200,200)"); 

complete demo here.