wip

connections.js

@@ -101,13 +101,13 @@ export const connections = function(superClass) {
       const canvasRect = this.canvas.getBoundingClientRect();
 
       const start = {
-        x: sourceRect.left + sourceRect.width/2 - canvasRect.left,
-        y: sourceRect.top + sourceRect.height/2 - canvasRect.top
+        x: (sourceRect.left + sourceRect.width/2 - canvasRect.left) / this.scale,
+        y: (sourceRect.top + sourceRect.height/2 - canvasRect.top) / this.scale
       };
       
       const end = {
-        x: this.mousePosition.x - canvasRect.left,
-        y: this.mousePosition.y - canvasRect.top
+        x: (this.mousePosition.x - canvasRect.left) / this.scale,
+        y: (this.mousePosition.y - canvasRect.top) / this.scale
       };
 
       const controlPoint1 = {
@@ -150,13 +150,13 @@ export const connections = function(superClass) {
       const canvasRect = this.canvas.getBoundingClientRect();
 
       const start = {
-        x: sourceRect.left + sourceRect.width/2 - canvasRect.left,
-        y: sourceRect.top + sourceRect.height/2 - canvasRect.top
+        x: (sourceRect.left + sourceRect.width/2 - canvasRect.left) / this.scale,
+        y: (sourceRect.top + sourceRect.height/2 - canvasRect.top) / this.scale
       };
       
       const end = {
-        x: targetRect.left + targetRect.width/2 - canvasRect.left,
-        y: targetRect.top + targetRect.height/2 - canvasRect.top
+        x: (targetRect.left + targetRect.width/2 - canvasRect.left) / this.scale,
+        y: (targetRect.top + targetRect.height/2 - canvasRect.top) / this.scale
       };
 
       const controlPoint1 = {

panning.js

@@ -73,8 +73,14 @@ export const panning = function(superClass) {
         this.xOffset = matrix.m41;
         this.yOffset = matrix.m42;
         
+        if (this.targetElement === this.canvas) {
           this.initialX = e.clientX - this.xOffset;
           this.initialY = e.clientY - this.yOffset;
+        } else {
+          // For nodes, compensate for scale in initial position too
+          this.initialX = e.clientX - (this.xOffset * this.scale);
+          this.initialY = e.clientY - (this.yOffset * this.scale);
+        }
       }
     }
 
@@ -82,13 +88,21 @@ export const panning = function(superClass) {
       if (this.isDragging && this.targetElement) {
         e.preventDefault();
         
+        if (this.targetElement === this.canvas) {
+          // For canvas panning, no scale compensation needed
           this.currentX = e.clientX - this.initialX;
           this.currentY = e.clientY - this.initialY;
-
+          this.targetElement.style.transform = 
+            `translate(${this.currentX}px, ${this.currentY}px) scale(${this.scale})`;
+        } else {
+          // For nodes, compensate for canvas scale
+          this.currentX = (e.clientX - this.initialX) / this.scale;
+          this.currentY = (e.clientY - this.initialY) / this.scale;
           this.targetElement.style.transform = 
             `translate(${this.currentX}px, ${this.currentY}px)`;
         }
       }
+    }
 
     _endDrag() {
       this.isDragging = false;

tp-flow-nodes.js

@@ -7,8 +7,9 @@ This program is available under Apache License Version 2.0
 import { LitElement, html, css } from 'lit';
 import { connections, connectionStyles } from './connections.js';
 import { panning } from './panning.js';
+import { zoom } from './zoom.js';
 
-class TpFlowNodes extends panning(connections(LitElement)) {
+class TpFlowNodes extends zoom(panning(connections(LitElement))) {
   static get styles() {
     return [
       connectionStyles,
@@ -23,8 +24,10 @@ class TpFlowNodes extends panning(connections(LitElement)) {
           width: 100%;
           height: 100%;
           user-select: none;
-          position: relative;
-          overflow: hidden;
+          position: absolute;
+          min-width: 100%;
+          min-height: 100%;
+          overflow: visible;
           transform: translate(0px, 0px);
         }
       `

zoom.js

@@ -0,0 +1,91 @@
+export const zoom = function(superClass) {
+  return class extends superClass {
+    static get properties() {
+      return {
+        scale: { type: Number }
+      };
+    }
+
+    constructor() {
+      super();
+      this.scale = 1;
+      this._handleWheel = this._handleWheel.bind(this);
+      this.MIN_SCALE = 0.1;
+      this.MAX_SCALE = 1.0;
+      this.SCALE_STEP = 0.1;
+    }
+
+    firstUpdated() {
+      super.firstUpdated();
+      this.canvas = this.shadowRoot.querySelector('.canvas');
+      this.addEventListener('wheel', this._handleWheel, { passive: false });
+    }
+
+    _handleWheel(e) {
+      e.preventDefault();
+      
+      if (e.deltaY > 0) {
+        this.zoomOut();
+      } else if (e.deltaY < 0) {
+        this.zoomIn();
+      }
+    }
+
+    /**
+     * Zooms out the canvas by one step
+     * @returns {boolean} True if zoom was applied, false if already at minimum
+     */
+    zoomOut() {
+      const newScale = Math.max(this.MIN_SCALE, this.scale - this.SCALE_STEP);
+      if (newScale !== this.scale) {
+        this._applyZoom(newScale);
+        return true;
+      }
+      return false;
+    }
+
+    /**
+     * Zooms in the canvas by one step
+     * @returns {boolean} True if zoom was applied, false if already at maximum
+     */
+    zoomIn() {
+      const newScale = Math.min(this.MAX_SCALE, this.scale + this.SCALE_STEP);
+      if (newScale !== this.scale) {
+        this._applyZoom(newScale);
+        return true;
+      }
+      return false;
+    }
+
+    /**
+     * Immediately resets zoom to 100%
+     */
+    resetZoom() {
+      this._applyZoom(this.MAX_SCALE);
+    }
+
+    /**
+     * Applies the zoom scale to the canvas
+     * @private
+     */
+    _applyZoom(newScale) {
+      this.scale = newScale;
+      
+      // Get current translation
+      const transform = window.getComputedStyle(this.canvas).transform;
+      const matrix = new DOMMatrix(transform);
+      const currentX = matrix.m41;
+      const currentY = matrix.m42;
+    
+      // Apply both transforms
+      this.canvas.style.transform = `translate(${currentX}px, ${currentY}px) scale(${this.scale})`;
+      this.canvas.style.transformOrigin = 'center center';
+      this.requestUpdate();
+    }
+
+    disconnectedCallback() {
+      super.disconnectedCallback();
+      this.removeEventListener('wheel', this._handleWheel);
+    }
+  };
+}