D3 Freehand Drawing. Stroke selection palette for marker pen and architectural pen

[Alison De Backer]

No , I am not a coder but a heritage enthusiast that would like to introduce my students to freehand drawing - the old fashioned way.

Problem: Need two palettes

• one for marker pen 0.2 opacity 13px wide
  
• one for architectural pen 0.9 opacity 1 px wide
  

I have cobbled together a D3 Block using existing code

Can't make the code work. Please help Freehand Doodles

[Vlado Z]

So your problem is the thickness and the opacity?

I think you can do that in the click listeners of your paint and pen buttons:

pen_btn = ui.append('text').html('').attr({
  "class": 'btn',
  dy: '0.35em',
  transform: 'translate(940,80)'
}).on('click', function() {
    drawing_data.lines = []; 
    active_opacity = "0.9";
    active_weight = "1px";
    return redraw();
  });
  
   paint_btn = ui.append('text').html('').attr({
  "class": 'btn',
  dy: '0.35em',
  transform: 'translate(940,140)'
}).on('click', function() {
    drawing_data.lines = [];  
    active_opacity = "0.2";
    active_weight = "13px";
    return redraw();
  });

[Alison De Backer]

Thanks Vlado.

I Kind of get the concept but I tried it in a JS Fiddle without success. 

I know what it is meant to do but not sure what code needs to be where. If you have a complete  JS Fiddle or Block I can fork I can copy with that would be great.

Cheers A

[Vlado Z]

Do yo still need work? I could possibly provide you with solution, but I am gonna have to charge something for the work if necessary.
Do you use Moneybookers(Skrill)?