From 654985c621121184c55141d0aa4fd8b0939acfff Mon Sep 17 00:00:00 2001
From: Jonas Jenwald <jonas.jenwald@gmail.com>
Date: Thu, 2 Apr 2026 22:28:17 +0200
Subject: [PATCH 1/2] Add constants for defining the initial BBox and Float32
 BBox

Nowadays there's a lot of places in the code-base where we need to initialize or reset bounding boxes. Rather than spelling this out repeatedly, this patch adds new `Array`/`Float32Array` constants that can be copied or used as-is where appropriate.
---
 src/core/annotation.js                   | 10 ++++++----
 src/core/evaluator.js                    | 17 +++++++----------
 src/core/pattern.js                      |  3 ++-
 src/display/canvas.js                    | 21 +++++++--------------
 src/display/canvas_dependency_tracker.js | 15 ++++++---------
 src/display/editor/drawers/freedraw.js   | 14 +++-----------
 src/display/editor/drawers/highlight.js  |  4 ++--
 src/display/editor/drawers/inkdraw.js    |  9 ++-------
 src/display/obj_bin_transform_display.js | 10 ++++++++--
 src/shared/util.js                       |  5 +++++
 10 files changed, 48 insertions(+), 60 deletions(-)

diff --git a/src/core/annotation.js b/src/core/annotation.js
index 8d38ec8ae..6e78864be 100644
--- a/src/core/annotation.js
+++ b/src/core/annotation.js
@@ -23,6 +23,8 @@ import {
   AnnotationType,
   assert,
   BASELINE_FACTOR,
+  BBOX_INIT,
+  F32_BBOX_INIT,
   FeatureTest,
   getModificationDate,
   info,
@@ -637,7 +639,7 @@ function getQuadPoints(dict, rect) {
 
 function getTransformMatrix(rect, bbox, matrix) {
   // 12.5.5: Algorithm: Appearance streams
-  const minMax = new Float32Array([Infinity, Infinity, -Infinity, -Infinity]);
+  const minMax = F32_BBOX_INIT.slice();
   Util.axialAlignedBoundingBox(bbox, matrix, minMax);
   const [minX, minY, maxX, maxY] = minMax;
   if (minX === maxX || minY === maxY) {
@@ -1724,7 +1726,7 @@ class MarkupAnnotation extends Annotation {
     fillAlpha,
     pointsCallback,
   }) {
-    const bbox = (this.data.rect = [Infinity, Infinity, -Infinity, -Infinity]);
+    const bbox = (this.data.rect = BBOX_INIT.slice());
 
     const buffer = ["q"];
     if (extra) {
@@ -4463,7 +4465,7 @@ class PolylineAnnotation extends MarkupAnnotation {
 
       // If the /Rect-entry is empty/wrong, create a fallback rectangle so that
       // we get similar rendering/highlighting behaviour as in Adobe Reader.
-      const bbox = [Infinity, Infinity, -Infinity, -Infinity];
+      const bbox = BBOX_INIT.slice();
       for (let i = 0, ii = vertices.length; i < ii; i += 2) {
         Util.rectBoundingBox(
           vertices[i] - borderAdjust,
@@ -4551,7 +4553,7 @@ class InkAnnotation extends MarkupAnnotation {
 
       // If the /Rect-entry is empty/wrong, create a fallback rectangle so that
       // we get similar rendering/highlighting behaviour as in Adobe Reader.
-      const bbox = [Infinity, Infinity, -Infinity, -Infinity];
+      const bbox = BBOX_INIT.slice();
       for (const inkList of this.data.inkLists) {
         for (let i = 0, ii = inkList.length; i < ii; i += 2) {
           Util.rectBoundingBox(
diff --git a/src/core/evaluator.js b/src/core/evaluator.js
index 7c51351d2..0ab0e524a 100644
--- a/src/core/evaluator.js
+++ b/src/core/evaluator.js
@@ -16,7 +16,9 @@
 import {
   AbortException,
   assert,
+  BBOX_INIT,
   DrawOPS,
+  F32_BBOX_INIT,
   FONT_IDENTITY_MATRIX,
   FormatError,
   info,
@@ -2309,7 +2311,7 @@ class PartialEvaluator {
                 pathMinMax.slice(),
               ]);
               pathBuffer.length = 0;
-              pathMinMax.set([Infinity, Infinity, -Infinity, -Infinity], 0);
+              pathMinMax.set(BBOX_INIT, 0);
             }
             continue;
           }
@@ -4980,7 +4982,7 @@ class TranslatedFont {
       // Override the fontBBox when it's undefined/empty, or when it's at least
       // (approximately) one order of magnitude smaller than the charBBox
       // (fixes issue14999_reduced.pdf).
-      this._bbox ??= [Infinity, Infinity, -Infinity, -Infinity];
+      this._bbox ??= BBOX_INIT.slice();
       Util.rectBoundingBox(...charBBox, this._bbox);
     }
 
@@ -5050,7 +5052,7 @@ class TranslatedFont {
         case OPS.constructPath:
           const minMax = operatorList.argsArray[i][2];
           // Override the fontBBox when it's undefined/empty (fixes 19624.pdf).
-          this._bbox ??= [Infinity, Infinity, -Infinity, -Infinity];
+          this._bbox ??= BBOX_INIT.slice();
           Util.rectBoundingBox(...minMax, this._bbox);
           break;
       }
@@ -5176,7 +5178,7 @@ class EvalState {
 
   currentPointY = 0;
 
-  pathMinMax = new Float32Array([Infinity, Infinity, -Infinity, -Infinity]);
+  pathMinMax = F32_BBOX_INIT.slice();
 
   pathBuffer = [];
 
@@ -5200,12 +5202,7 @@ class EvalState {
     const clone = Object.create(this);
     if (newPath) {
       clone.pathBuffer = [];
-      clone.pathMinMax = new Float32Array([
-        Infinity,
-        Infinity,
-        -Infinity,
-        -Infinity,
-      ]);
+      clone.pathMinMax = F32_BBOX_INIT.slice();
     }
     return clone;
   }
diff --git a/src/core/pattern.js b/src/core/pattern.js
index 161e16a1f..e153b54d5 100644
--- a/src/core/pattern.js
+++ b/src/core/pattern.js
@@ -15,6 +15,7 @@
 
 import {
   assert,
+  BBOX_INIT,
   FormatError,
   info,
   MeshFigureType,
@@ -426,7 +427,7 @@ class FunctionBasedShading extends BaseShading {
     const matrix = lookupMatrix(dict.getArray("Matrix"), IDENTITY_MATRIX);
 
     // Transform the four domain corners to find the user-space bounding box.
-    this.bounds = [Infinity, Infinity, -Infinity, -Infinity];
+    this.bounds = BBOX_INIT.slice();
     Util.axialAlignedBoundingBox([x0, y0, x1, y1], matrix, this.bounds);
 
     const bboxW = this.bounds[2] - this.bounds[0];
diff --git a/src/display/canvas.js b/src/display/canvas.js
index d39b566a0..f65df318d 100644
--- a/src/display/canvas.js
+++ b/src/display/canvas.js
@@ -18,6 +18,7 @@ import {
   Dependencies,
 } from "./canvas_dependency_tracker.js";
 import {
+  F32_BBOX_INIT,
   FeatureTest,
   FONT_IDENTITY_MATRIX,
   ImageKind,
@@ -66,14 +67,6 @@ const SCALE_MATRIX = new DOMMatrix();
 // Used to get some coordinates.
 const XY = new Float32Array(2);
 
-// Initial rectangle values for the minMax array.
-const MIN_MAX_INIT = new Float32Array([
-  Infinity,
-  Infinity,
-  -Infinity,
-  -Infinity,
-]);
-
 /**
  * Overrides certain methods on a 2d ctx so that when they are called they
  * will also call the same method on the destCtx. The methods that are
@@ -335,7 +328,7 @@ class CanvasExtraState {
 
   transferMaps = "none";
 
-  minMax = MIN_MAX_INIT.slice();
+  minMax = F32_BBOX_INIT.slice();
 
   constructor(width, height) {
     this.clipBox = new Float32Array([0, 0, width, height]);
@@ -379,7 +372,7 @@ class CanvasExtraState {
 
   startNewPathAndClipBox(box) {
     this.clipBox.set(box, 0);
-    this.minMax.set(MIN_MAX_INIT, 0);
+    this.minMax.set(F32_BBOX_INIT, 0);
   }
 
   getClippedPathBoundingBox(pathType = PathType.FILL, transform = null) {
@@ -1056,7 +1049,7 @@ class CanvasGraphics {
       0,
     ]);
     maskToCanvas = Util.transform(maskToCanvas, [1, 0, 0, 1, 0, -height]);
-    const minMax = MIN_MAX_INIT.slice();
+    const minMax = F32_BBOX_INIT.slice();
     Util.axialAlignedBoundingBox([0, 0, width, height], maskToCanvas, minMax);
     const [minX, minY, maxX, maxY] = minMax;
     const drawnWidth = Math.round(maxX - minX) || 1;
@@ -2529,7 +2522,7 @@ class CanvasGraphics {
     const inv = getCurrentTransformInverse(ctx);
     if (inv) {
       const { width, height } = ctx.canvas;
-      const minMax = MIN_MAX_INIT.slice();
+      const minMax = F32_BBOX_INIT.slice();
       Util.axialAlignedBoundingBox([0, 0, width, height], inv, minMax);
       const [x0, y0, x1, y1] = minMax;
 
@@ -2675,7 +2668,7 @@ class CanvasGraphics {
 
     let bounds;
     if (group.bbox) {
-      bounds = MIN_MAX_INIT.slice();
+      bounds = F32_BBOX_INIT.slice();
       Util.axialAlignedBoundingBox(
         group.bbox,
         getCurrentTransform(currentCtx),
@@ -2804,7 +2797,7 @@ class CanvasGraphics {
       this.restore(opIdx);
       this.ctx.save();
       this.ctx.setTransform(...currentMtx);
-      const dirtyBox = MIN_MAX_INIT.slice();
+      const dirtyBox = F32_BBOX_INIT.slice();
       Util.axialAlignedBoundingBox(
         [0, 0, groupCtx.canvas.width, groupCtx.canvas.height],
         currentMtx,
diff --git a/src/display/canvas_dependency_tracker.js b/src/display/canvas_dependency_tracker.js
index 936f10666..55ac72d38 100644
--- a/src/display/canvas_dependency_tracker.js
+++ b/src/display/canvas_dependency_tracker.js
@@ -13,7 +13,7 @@
  * limitations under the License.
  */
 
-import { FeatureTest, Util } from "../shared/util.js";
+import { BBOX_INIT, FeatureTest, Util } from "../shared/util.js";
 import { MathClamp } from "../shared/math_clamp.js";
 
 const FORCED_DEPENDENCY_LABEL = "__forcedDependency";
@@ -81,7 +81,7 @@ class CanvasBBoxTracker {
   #clipBox = [-Infinity, -Infinity, Infinity, Infinity];
 
   // Float32Array<minX, minY, maxX, maxY>
-  #pendingBBox = new Float64Array([Infinity, Infinity, -Infinity, -Infinity]);
+  #pendingBBox = new Float64Array(BBOX_INIT);
 
   _pendingBBoxIdx = -1;
 
@@ -209,10 +209,7 @@ class CanvasBBoxTracker {
   resetBBox(idx) {
     if (this._pendingBBoxIdx !== idx) {
       this._pendingBBoxIdx = idx;
-      this.#pendingBBox[0] = Infinity;
-      this.#pendingBBox[1] = Infinity;
-      this.#pendingBBox[2] = -Infinity;
-      this.#pendingBBox[3] = -Infinity;
+      this.#pendingBBox.set(BBOX_INIT, 0);
     }
     return this;
   }
@@ -222,7 +219,7 @@ class CanvasBBoxTracker {
       this.#baseTransformStack.at(-1),
       ctx.getTransform()
     );
-    const clipBox = [Infinity, Infinity, -Infinity, -Infinity];
+    const clipBox = BBOX_INIT.slice();
     Util.axialAlignedBoundingBox([minX, minY, maxX, maxY], transform, clipBox);
     const intersection = Util.intersect(this.#clipBox, clipBox);
     if (intersection) {
@@ -256,7 +253,7 @@ class CanvasBBoxTracker {
       return this;
     }
 
-    const bbox = [Infinity, Infinity, -Infinity, -Infinity];
+    const bbox = BBOX_INIT.slice();
     Util.axialAlignedBoundingBox([minX, minY, maxX, maxY], transform, bbox);
 
     this.#pendingBBox[0] = MathClamp(bbox[0], clipBox[0], this.#pendingBBox[0]);
@@ -1130,7 +1127,7 @@ class CanvasImagesTracker {
     let coords;
 
     if (clipBox[0] !== Infinity) {
-      const bbox = [Infinity, Infinity, -Infinity, -Infinity];
+      const bbox = BBOX_INIT.slice();
       Util.axialAlignedBoundingBox([0, -height, width, 0], transform, bbox);
 
       const finalBBox = Util.intersect(clipBox, bbox);
diff --git a/src/display/editor/drawers/freedraw.js b/src/display/editor/drawers/freedraw.js
index 8300ca3b3..7ec0517f0 100644
--- a/src/display/editor/drawers/freedraw.js
+++ b/src/display/editor/drawers/freedraw.js
@@ -13,8 +13,8 @@
  * limitations under the License.
  */
 
+import { BBOX_INIT, Util } from "../../../shared/util.js";
 import { Outline } from "./outline.js";
-import { Util } from "../../../shared/util.js";
 
 class FreeDrawOutliner {
   #box;
@@ -588,22 +588,14 @@ class FreeDrawOutline extends Outline {
           lastPointX = ltrCallback(lastPointX, x);
         }
       } else {
-        bezierBbox[0] = bezierBbox[1] = Infinity;
-        bezierBbox[2] = bezierBbox[3] = -Infinity;
+        bezierBbox.set(BBOX_INIT, 0);
         Util.bezierBoundingBox(
           lastX,
           lastY,
           ...outline.slice(i, i + 6),
           bezierBbox
         );
-
-        Util.rectBoundingBox(
-          bezierBbox[0],
-          bezierBbox[1],
-          bezierBbox[2],
-          bezierBbox[3],
-          minMax
-        );
+        Util.rectBoundingBox(...bezierBbox, minMax);
 
         if (firstPointY > bezierBbox[1]) {
           firstPointX = bezierBbox[0];
diff --git a/src/display/editor/drawers/highlight.js b/src/display/editor/drawers/highlight.js
index 2809dd5aa..eab8c8fab 100644
--- a/src/display/editor/drawers/highlight.js
+++ b/src/display/editor/drawers/highlight.js
@@ -13,9 +13,9 @@
  * limitations under the License.
  */
 
+import { BBOX_INIT, Util } from "../../../shared/util.js";
 import { FreeDrawOutline, FreeDrawOutliner } from "./freedraw.js";
 import { Outline } from "./outline.js";
-import { Util } from "../../../shared/util.js";
 
 class HighlightOutliner {
   #box;
@@ -41,7 +41,7 @@ class HighlightOutliner {
    *   the last point of the boxes.
    */
   constructor(boxes, borderWidth = 0, innerMargin = 0, isLTR = true) {
-    const minMax = [Infinity, Infinity, -Infinity, -Infinity];
+    const minMax = BBOX_INIT.slice();
 
     // We round the coordinates to slightly reduce the number of edges in the
     // final outlines.
diff --git a/src/display/editor/drawers/inkdraw.js b/src/display/editor/drawers/inkdraw.js
index 3ecf3af8a..a7cde0f1e 100644
--- a/src/display/editor/drawers/inkdraw.js
+++ b/src/display/editor/drawers/inkdraw.js
@@ -13,9 +13,9 @@
  * limitations under the License.
  */
 
+import { F32_BBOX_INIT, Util } from "../../../shared/util.js";
 import { MathClamp } from "../../../shared/math_clamp.js";
 import { Outline } from "./outline.js";
-import { Util } from "../../../shared/util.js";
 
 class InkDrawOutliner {
   // The last 3 points of the line.
@@ -587,12 +587,7 @@ class InkDrawOutline extends Outline {
   }
 
   #computeBbox() {
-    const bbox = (this.#bbox = new Float32Array([
-      Infinity,
-      Infinity,
-      -Infinity,
-      -Infinity,
-    ]));
+    const bbox = (this.#bbox = F32_BBOX_INIT.slice());
 
     for (const { line } of this.#lines) {
       if (line.length <= 12) {
diff --git a/src/display/obj_bin_transform_display.js b/src/display/obj_bin_transform_display.js
index a2db53d7e..30dabaae3 100644
--- a/src/display/obj_bin_transform_display.js
+++ b/src/display/obj_bin_transform_display.js
@@ -13,7 +13,13 @@
  * limitations under the License.
  */
 
-import { assert, FeatureTest, MeshFigureType, Util } from "../shared/util.js";
+import {
+  assert,
+  BBOX_INIT,
+  FeatureTest,
+  MeshFigureType,
+  Util,
+} from "../shared/util.js";
 import {
   CSS_FONT_INFO,
   FONT_INFO,
@@ -438,7 +444,7 @@ class PatternInfo {
       const shadingType = this.data[PATTERN_INFO.SHADING_TYPE];
       let bounds = null;
       if (coords.length > 0) {
-        bounds = [Infinity, Infinity, -Infinity, -Infinity];
+        bounds = BBOX_INIT.slice();
 
         for (let i = 0, ii = coords.length; i < ii; i += 2) {
           Util.pointBoundingBox(coords[i], coords[i + 1], bounds);
diff --git a/src/shared/util.js b/src/shared/util.js
index 778fcbd89..ec0be9a9e 100644
--- a/src/shared/util.js
+++ b/src/shared/util.js
@@ -25,6 +25,9 @@ const isNodeJS =
   !process.versions.nw &&
   !(process.versions.electron && process.type && process.type !== "browser");
 
+const BBOX_INIT = [Infinity, Infinity, -Infinity, -Infinity];
+const F32_BBOX_INIT = new Float32Array(BBOX_INIT);
+
 const FONT_IDENTITY_MATRIX = [0.001, 0, 0, 0.001, 0, 0];
 
 // Represent the percentage of the height of a single-line field over
@@ -1310,10 +1313,12 @@ export {
   assert,
   BaseException,
   BASELINE_FACTOR,
+  BBOX_INIT,
   bytesToString,
   createValidAbsoluteUrl,
   DocumentActionEventType,
   DrawOPS,
+  F32_BBOX_INIT,
   FeatureTest,
   FONT_IDENTITY_MATRIX,
   FormatError,

From 0fd556f435a5cfe49cff3af3a91763fc4384e31a Mon Sep 17 00:00:00 2001
From: Jonas Jenwald <jonas.jenwald@gmail.com>
Date: Fri, 3 Apr 2026 10:36:19 +0200
Subject: [PATCH 2/2] Take full advantage of the `lookupRect` helper in the
 `FunctionBasedShading` constructor

---
 src/core/pattern.js | 9 +--------
 1 file changed, 1 insertion(+), 8 deletions(-)

diff --git a/src/core/pattern.js b/src/core/pattern.js
index e153b54d5..7cdee3fc3 100644
--- a/src/core/pattern.js
+++ b/src/core/pattern.js
@@ -414,14 +414,7 @@ class FunctionBasedShading extends BaseShading {
     const fn = pdfFunctionFactory.create(fnObj, /* parseArray = */ true);
 
     // Domain [x0, x1, y0, y1]; defaults to [0, 1, 0, 1].
-    let x0 = 0,
-      x1 = 1,
-      y0 = 0,
-      y1 = 1;
-    const domainArr = lookupRect(dict.getArray("Domain"), null);
-    if (domainArr) {
-      [x0, x1, y0, y1] = domainArr;
-    }
+    const [x0, x1, y0, y1] = lookupRect(dict.getArray("Domain"), [0, 1, 0, 1]);
 
     // Matrix maps shading (domain) space to user space; defaults to identity.
     const matrix = lookupMatrix(dict.getArray("Matrix"), IDENTITY_MATRIX);