Visually show when 2 pshape lines cross - transparency?

Processing Project Guidance
1

Hi, I’m simply drawing lines for a schematic program using PShapes, and I want some visual indication when lines cross. I’d like to do this by controlling the transparency of the PShape lines so that a crossing would show darker at the at location.

I’ve looked at a lot of threads, talking about tints, alpha, etc, but nothing is what I’m looking for or I’m missing something simple.

Suggestions? Thanks!

2

Can you please show your code or relevant part

3

Hi Chrisir,
It’s not very exciting code, I’ll just post a fragment here. As the user draws, it adds sections to the “hose” in grey, then when done, it turns blue.

 void addHose(int lastX, lastY, endY){
    hose = createShape(LINE,lastX, lastY, lastX, endY);
    
    hose.setStroke(128);      // draw in gray as hoses are added
    hose.setStrokeWeight(10.0);
    
    hoseGroup.addChild(hose);
    hosepart++;
    created = true;
  }
  
  void finish(){
    hoseGroup.disableStyle();
    stroke(0,0,150);       // draw in blue once completed all hoses
    strokeWeight(10);
    shape(hoseGroup);
  }
4

You can work with smaller opacity - see fill in the reference

Also look at blendMode() in the reference

5

Thanks, I’ll check out blendMode(), also I just got alpha to work with stroke().
-MH