use luminosity mask by default

Author: AshishBhattarai

lib/write_svg.js

@@ -689,7 +689,7 @@ export default function (doc, svg, x, y, options) {
     doc.page.xobjects[group.name] = group.xobj;
     doc.addContent('/' + group.name + ' Do');
   }
-  function docApplyMask(group) {
+  function docApplyAlphaMask(group) {
     let name = 'M' + (doc._maskCount = (doc._maskCount || 0) + 1);
     let gstate = doc.ref({
       Type: 'ExtGState',
@@ -706,6 +706,22 @@ export default function (doc, svg, x, y, options) {
     doc.page.ext_gstates[name] = gstate;
     doc.addContent('/' + name + ' gs');
   }
+  function docApplyMask(group) {
+    let name = 'M' + (doc._maskCount = (doc._maskCount || 0) + 1);
+    let gstate = doc.ref({
+      Type: 'ExtGState',
+      CA: 1,
+      ca: 1,
+      BM: 'Normal',
+      SMask: {
+        S: 'Luminosity',
+        G: group.xobj,
+      },
+    });
+    gstate.end();
+    doc.page.ext_gstates[name] = gstate;
+    doc.addContent('/' + name + ' gs');
+  }
   function applyBlendMode(group, blendMode) {
     // map svg blendMode to pdf
     const key = String(blendMode || '').toLowerCase();
@@ -3297,7 +3313,7 @@ export default function (doc, svg, x, y, options) {
       this.drawChildren(true, false);
       doc.restore();
       docEndGroup(group);
-      docApplyMask(group);
+      docApplyAlphaMask(group);
     };
   };
 
@@ -3321,11 +3337,16 @@ export default function (doc, svg, x, y, options) {
       if (this.attr('maskContentUnits') === 'objectBoundingBox') {
         doc.transform(bBox[2] - bBox[0], 0, 0, bBox[3] - bBox[1], bBox[0], bBox[1]);
       }
+      const maskType = this.attr('mask-type') ?? 'luminance';
       this.clip();
       this.drawChildren(false, true);
       doc.restore();
       docEndGroup(group);
-      docApplyMask(group);
+      if (maskType === 'alpha') {
+        docApplyAlphaMask(group);
+      } else {
+        docApplyMask(group);
+      }
     };
   };
 

package.json

@@ -9,7 +9,7 @@
     "document",
     "vector"
   ],
-  "version": "0.17.56",
+  "version": "0.17.57",
   "homepage": "http://pdfkit.org/",
   "author": {
     "name": "Devon Govett",