Avoid to create an array when setting the text matrix

Author: calixteman

src/core/evaluator.js

@@ -2237,6 +2237,9 @@ class PartialEvaluator {
             }
             continue;
           }
+          case OPS.setTextMatrix:
+            operatorList.addOp(fn, [new Float32Array(args)]);
+            continue;
           case OPS.markPoint:
           case OPS.markPointProps:
           case OPS.beginCompat:

src/core/operator_list.js

@@ -787,6 +787,9 @@ class OperatorList {
             transfers.push(bbox.buffer);
           }
           break;
+        case OPS.setTextMatrix:
+          transfers.push(argsArray[i][0].buffer);
+          break;
       }
     }
     return transfers;

src/display/canvas.js

@@ -17,7 +17,6 @@ import {
   DrawOPS,
   FeatureTest,
   FONT_IDENTITY_MATRIX,
-  IDENTITY_MATRIX,
   ImageKind,
   info,
   OPS,
@@ -311,7 +310,7 @@ class CanvasExtraState {
 
   fontSizeScale = 1;
 
-  textMatrix = IDENTITY_MATRIX;
+  textMatrix = null;
 
   textMatrixScale = 1;
 
@@ -1611,7 +1610,7 @@ class CanvasGraphics {
 
   // Text
   beginText() {
-    this.current.textMatrix = IDENTITY_MATRIX;
+    this.current.textMatrix = null;
     this.current.textMatrixScale = 1;
     this.current.x = this.current.lineX = 0;
     this.current.y = this.current.lineY = 0;
@@ -1732,12 +1731,13 @@ class CanvasGraphics {
     this.moveText(x, y);
   }
 
-  setTextMatrix(a, b, c, d, e, f) {
-    this.current.textMatrix = [a, b, c, d, e, f];
-    this.current.textMatrixScale = Math.hypot(a, b);
+  setTextMatrix(matrix) {
+    const { current } = this;
+    current.textMatrix = matrix;
+    current.textMatrixScale = Math.hypot(matrix[0], matrix[1]);
 
-    this.current.x = this.current.lineX = 0;
-    this.current.y = this.current.lineY = 0;
+    current.x = current.lineX = 0;
+    current.y = current.lineY = 0;
   }
 
   nextLine() {
@@ -1904,7 +1904,9 @@ class CanvasGraphics {
       !current.patternFill;
 
     ctx.save();
-    ctx.transform(...current.textMatrix);
+    if (current.textMatrix) {
+      ctx.transform(...current.textMatrix);
+    }
     ctx.translate(current.x, current.y + current.textRise);
 
     if (fontDirection > 0) {
@@ -2099,7 +2101,9 @@ class CanvasGraphics {
     this._cachedGetSinglePixelWidth = null;
 
     ctx.save();
-    ctx.transform(...current.textMatrix);
+    if (current.textMatrix) {
+      ctx.transform(...current.textMatrix);
+    }
     ctx.translate(current.x, current.y + current.textRise);
 
     ctx.scale(textHScale, fontDirection);