Provide href attribute support in a elements

src/nodes/anchor.ts

@@ -0,0 +1,19 @@
+import { Group } from './group'
+import { Context } from '../context/context'
+import { getAttribute } from '../utils/node'
+
+export class Anchor extends Group {
+  protected async renderCore(context: Context): Promise<void> {
+    await super.renderCore(context)
+
+    const href = getAttribute(this.element, context.styleSheets, 'href')
+    if (href) {
+      const box = this.getBoundingBox(context)
+      const scale = context.pdf.internal.scaleFactor
+      const ph = context.pdf.internal.pageSize.getHeight()
+
+      context.pdf.link(scale*(box[0] * context.transform.sx + context.transform.tx),
+                       ph - scale*(box[1] * context.transform.sy + context.transform.ty), scale*box[2], scale*box[3], { url: href })
+    }
+  }
+}

src/nodes/text.ts

@@ -24,6 +24,7 @@ interface TrimInfo {
 }
 
 export class TextNode extends GraphicsNode {
+  private boundingBox: number[] = []
   private processTSpans(
     textNode: SvgNode,
     node: Element,
@@ -159,6 +160,7 @@ export class TextNode extends GraphicsNode {
           renderingMode: textRenderingMode === 'fill' ? void 0 : textRenderingMode,
           charSpace: charSpace === 0 ? void 0 : charSpace
         })
+        this.boundingBox = [textX + dx - xOffset, textY + dy + 0.1 * pdfFontSize, context.textMeasure.measureTextWidth(transformedText, context.attributeState), pdfFontSize]
       }
     } else {
       // otherwise loop over tspans and position each relative to the previous one
@@ -228,7 +230,7 @@ export class TextNode extends GraphicsNode {
   }
 
   protected getBoundingBoxCore(context: Context): Rect {
-    return defaultBoundingBox(this.element, context)
+    return this.boundingBox.length > 0 ? this.boundingBox : defaultBoundingBox(this.element, context)
   }
 
   protected computeNodeTransformCore(context: Context): Matrix {

src/parse.ts

@@ -17,6 +17,7 @@ import { RadialGradient } from './nodes/radialgradient'
 import { Polyline } from './nodes/polyline'
 import { Svg } from './nodes/svg'
 import { Group } from './nodes/group'
+import { Anchor } from './nodes/anchor'
 import cssesc from 'cssesc'
 import { ClipPath } from './nodes/clippath'
 import { Symbol } from './nodes/symbol'
@@ -29,6 +30,8 @@ export function parse(node: Element, idMap?: { [id: string]: SvgNode }): SvgNode
 
   switch (node.tagName.toLowerCase()) {
     case 'a':
+      svgnode = new Anchor(node, children)
+      break
     case 'g':
       svgnode = new Group(node, children)
       break

src/utils/bbox.ts

@@ -7,9 +7,20 @@ export function getBoundingBoxByChildren(context: Context, svgnode: SvgNode): nu
   if (getAttribute(svgnode.element, context.styleSheets, 'display') === 'none') {
     return [0, 0, 0, 0]
   }
-  let boundingBox = [0, 0, 0, 0]
+  let boundingBox : number[] = []
   svgnode.children.forEach(child => {
     const nodeBox = child.getBoundingBox(context)
+    if ((nodeBox[0] === 0) && (nodeBox[1] === 0) && (nodeBox[2] === 0) && (nodeBox[3] === 0))
+       return
+    const transform = child.computeNodeTransform(context)
+    // TODO: take into account rotation matrix
+    nodeBox[0] = nodeBox[0] * transform.sx + transform.tx
+    nodeBox[1] = nodeBox[1] * transform.sy + transform.ty
+    nodeBox[2] = nodeBox[2] * transform.sx
+    nodeBox[3] = nodeBox[3] * transform.sy
+    if (boundingBox.length === 0)
+      boundingBox = nodeBox
+    else
     boundingBox = [
       Math.min(boundingBox[0], nodeBox[0]),
       Math.min(boundingBox[1], nodeBox[1]),
@@ -19,7 +30,7 @@ export function getBoundingBoxByChildren(context: Context, svgnode: SvgNode): nu
         Math.min(boundingBox[1], nodeBox[1])
     ]
   })
-  return boundingBox
+  return boundingBox.length === 0 ? [0, 0, 0, 0] : boundingBox
 }
 
 export function defaultBoundingBox(element: Element, context: Context): Rect {

test/common/tests.js

@@ -1,4 +1,5 @@
 window.tests = [
+  'anchor',
   'attribute-style-precedence',
   'clippath',
   'clippath-empty',