initial

build/application.linux-arm64/source/links.pde

@@ -0,0 +1,60 @@
+int linkCount;
+
+boolean dragLink; //state of dragging a link
+int dragOriginLet = 0; //dragging from inlet: -1. dragging from outlet: 1.
+int dragOriginId = -1; //which nodes out- / inlet did user click on?
+
+void Link(int parentNode, int targetNode) {
+  /**
+   * Check if user is adding or removing a link
+   */
+  int exists = -1;
+  for (int i = 0; i < linkCount; i++) {
+    if (links[i].parentNode == parentNode && links[i].targetNode == targetNode) {
+      exists = i;
+      break;
+    }
+  }
+  if (exists != -1) {
+    /**
+     * !active state is pretty much the same as deleted state that the node-class comes with
+     */
+    links[exists].active = !links[exists].active;
+  } else {
+    links[linkCount] = new Link(parentNode, targetNode);
+    linkCount++;
+  }
+}
+
+class Link {
+  int parentNode, targetNode;
+  boolean active;
+  PVector link = new PVector(0, 0);
+
+  Link(int parentNode_, int targetNode_) {
+    parentNode = parentNode_;
+    targetNode = targetNode_;
+    active = true;
+  }
+
+  /**
+   * This could be an event that only gets called when nodes are moved or resized.
+   */
+  void update() {
+    link.x = nodes[targetNode].inletCenter.x - nodes[parentNode].outletCenter.x;
+    link.y = nodes[targetNode].inletCenter.y - nodes[parentNode].outletCenter.y;
+  }
+
+  void display() {
+    stroke(darkMode? 255 : 0);
+    strokeWeight(2);
+    pushMatrix();
+    translate(nodes[parentNode].outletCenter.x, nodes[parentNode].outletCenter.y);
+    line(0, 0, link.x, link.y);
+    translate(-nodes[parentNode].outletCenter.x+(nodes[parentNode].outletCenter.x+nodes[targetNode].inletCenter.x)/2, -nodes[parentNode].outletCenter.y+(nodes[parentNode].outletCenter.y+nodes[targetNode].inletCenter.y)/2);
+    rotate(link.heading());
+    fill(darkMode? 0 : 255);
+    triangle(0, textSize/2, textSize, 0, 0, -textSize/2);
+    popMatrix();
+  }
+}