Correctly render the glyph outline when it has a stroke pattern

It fixes #19360.

Each glyph in the test case has a fill and a stroke pattern, so the current transform used
to scale the glyph outline must be the same.
In setting the stroke color to green, I noticed that the last outline contains some non-closed
subpaths, so when generating the glyph outline, every time we 'moveTo', we close the previous
subpath.

src/core/font_renderer.js

@@ -170,6 +170,11 @@ function lookupCmap(ranges, unicode) {
 
 function compileGlyf(code, cmds, font) {
   function moveTo(x, y) {
+    if (firstPoint) {
+      // Close the current subpath in adding a straight line to the first point.
+      cmds.add("L", firstPoint);
+    }
+    firstPoint = [x, y];
     cmds.add("M", [x, y]);
   }
   function lineTo(x, y) {
@@ -182,6 +187,7 @@ function compileGlyf(code, cmds, font) {
   let i = 0;
   const numberOfContours = getInt16(code, i);
   let flags;
+  let firstPoint = null;
   let x = 0,
     y = 0;
   i += 10;
@@ -350,6 +356,11 @@ function compileGlyf(code, cmds, font) {
 
 function compileCharString(charStringCode, cmds, font, glyphId) {
   function moveTo(x, y) {
+    if (firstPoint) {
+      // Close the current subpath in adding a straight line to the first point.
+      cmds.add("L", firstPoint);
+    }
+    firstPoint = [x, y];
     cmds.add("M", [x, y]);
   }
   function lineTo(x, y) {
@@ -363,6 +374,7 @@ function compileCharString(charStringCode, cmds, font, glyphId) {
   let x = 0,
     y = 0;
   let stems = 0;
+  let firstPoint = null;
 
   function parse(code) {
     let i = 0;

src/display/canvas.js

@@ -2043,12 +2043,13 @@ class CanvasGraphics {
       ctx.save();
       ctx.translate(x, y);
       ctx.scale(fontSize, -fontSize);
+      let currentTransform;
       if (
         fillStrokeMode === TextRenderingMode.FILL ||
         fillStrokeMode === TextRenderingMode.FILL_STROKE
       ) {
         if (patternFillTransform) {
-          const currentTransform = ctx.getTransform();
+          currentTransform = ctx.getTransform();
           ctx.setTransform(...patternFillTransform);
           ctx.fill(
             this.#getScaledPath(path, currentTransform, patternFillTransform)
@@ -2062,8 +2063,22 @@ class CanvasGraphics {
         fillStrokeMode === TextRenderingMode.FILL_STROKE
       ) {
         if (patternStrokeTransform) {
-          const currentTransform = ctx.getTransform();
+          currentTransform ||= ctx.getTransform();
           ctx.setTransform(...patternStrokeTransform);
+          const { a, b, c, d } = currentTransform;
+          const invPatternTransform = Util.inverseTransform(
+            patternStrokeTransform
+          );
+          const transf = Util.transform(
+            [a, b, c, d, 0, 0],
+            invPatternTransform
+          );
+          const [sx, sy] = Util.singularValueDecompose2dScale(transf);
+
+          // Cancel the pattern scaling of the line width.
+          // If sx and sy are different, unfortunately we can't do anything and
+          // we'll have a rendering bug.
+          ctx.lineWidth *= Math.max(sx, sy) / fontSize;
           ctx.stroke(
             this.#getScaledPath(path, currentTransform, patternStrokeTransform)
           );

test/pdfs/.gitignore

@@ -696,3 +696,4 @@
 !issue18911.pdf
 !issue19207.pdf
 !issue19239.pdf
+!issue19360.pdf

test/test_manifest.json

@@ -11286,5 +11286,12 @@
     "firstPage": 2,
     "lastPage": 2,
     "type": "eq"
+  },
+  {
+    "id": "issue19360",
+    "file": "pdfs/issue19360.pdf",
+    "md5": "b2de376f7e96fa2b6afc00dac016c40a",
+    "rounds": 1,
+    "type": "eq"
   }
 ]