Fix forward SyncTex accuracy in internal browser by providing a range location indication alternative

package.json

@@ -1670,9 +1670,19 @@
         },
         "latex-workshop.synctex.indicator.enabled": {
           "scope": "window",
-          "type": "boolean",
-          "default": true,
-          "markdownDescription": "Define the visibility of SyncTeX indicator (a red highlighting circle) after a forward SyncTeX in the PDF viewer."
+          "type": "string",
+          "enum": [
+            "disabled",
+            "spot",
+            "range"
+          ],
+          "enumDescriptions": [
+            "Disable indicator.",
+            "Indicates a single specific spot with a red circle SyncTeX indicator.",
+            "Indicates a possible range with a blue rectangular SyncTeX indicator. (Valid when not using synctex.js)"
+          ],
+          "default": "spot",
+          "markdownDescription": "Define the visibility and style of SyncTeX indicator after a forward SyncTeX in the PDF viewer."
         },
         "latex-workshop.synctex.afterBuild.enabled": {
           "scope": "window",

src/locate/synctex.ts

@@ -3,7 +3,7 @@ import * as fs from 'fs'
 import * as path from 'path'
 import * as cs from 'cross-spawn'
 import { lw } from '../lw'
-import type { SyncTeXRecordToPDF, SyncTeXRecordToTeX } from '../types'
+import type { SyncTeXRecordToPDF, SyncTeXRecordToPDFAll, SyncTeXRecordToTeX } from '../types'
 import { syncTeXToPDF, syncTeXToTeX } from './synctex/worker'
 import { replaceArgumentPlaceholders } from '../utils/utils'
 import { isSameRealPath } from '../utils/pathnormalize'
@@ -61,6 +61,72 @@ function parseToPDF(result: string): SyncTeXRecordToPDF {
     }
 }
 
+/**
+ * Parse the result of SyncTeX forward to PDF with a list.
+ *
+ * This function takes the result of SyncTeX forward to PDF as a string and
+ * parses it to extract page number, x-coordinate, y-coordinate, box-based 
+ * coordinates (h, v, H, W), and whether the red indicator should be shown 
+ * in the viewer.
+ *
+ * @param result - The result string of SyncTeX forward to PDF.
+ * @returns A SyncTeXRecordToPDFAllList object containing a list of records, 
+ * with each record containing page number, x-coordinate, y-coordinate, 
+ * h-coordinate, v-coordinate, H-coordinate, W-coordinate, and an indicator.
+ * @throws Error if there is a parsing error.
+ */
+function parseToPDFList(result: string): SyncTeXRecordToPDFAll[] {
+    const records: SyncTeXRecordToPDFAll[] = [];
+    let started = false;
+    let recordIndex = -1;
+
+    for (const line of result.split('\n')) {
+        if (line.includes('SyncTeX result begin')) {
+            started = true;
+            continue;
+        }
+
+        if (line.includes('SyncTeX result end')) {
+            break;
+        }
+
+        if (!started) {
+            continue;
+        }
+
+        const pos = line.indexOf(':');
+        if (pos < 0) {
+            continue;
+        }
+
+        const key = line.substring(0, pos);
+        const value = line.substring(pos + 1).trim();
+
+        if (key == 'Output') {
+            recordIndex += 1;
+            const record : SyncTeXRecordToPDFAll = { page: 0, x: 0, y: 0, h: 0, v: 0, W: 0, H: 0, indicator: true };
+            records[recordIndex] = record;
+        }
+
+        if (key === 'Page' || key === 'h' || key === 'v' || key === 'W' || key === 'H' || key === 'x' || key === 'y') {
+            const record = records[recordIndex];
+            if (record) {
+                if (key === 'Page') {
+                    record['page'] = Number(value)
+                } else {
+                    record[key] = Number(value);
+                }
+            }
+        }
+    }
+
+    if (recordIndex != -1) {
+        return records;
+    } else {
+        throw(new Error('parse error when parsing the result of synctex forward.'))
+    }
+}
+
 /**
  * Parse the result of SyncTeX backward to TeX.
  *
@@ -181,11 +247,30 @@ function toPDF(args?: {line: number, filePath: string}, forcedViewer: 'auto' | '
             logger.logError('Forward SyncTeX failed.', e)
         }
     } else {
-        void callSyncTeXToPDF(line, character, filePath, pdfFile).then( (record) => {
+        let indicatorType: string;
+
+        const indicatorConfig = configuration.get('synctex.indicator.enabled')
+
+        if (typeof indicatorConfig === "boolean") {
+            // if configuration is boolean in previous version, then use fallback logic.
+            if (indicatorConfig) {
+                indicatorType = "spot"
+            } else {
+                indicatorType = "disabled"
+            }
+        } else if (typeof indicatorConfig === "string") {
+            // if configuration is enum, then use directly.
+            indicatorType = indicatorConfig;
+        } else {
+            throw new Error("Invalid configuration value for indicator enabled");
+        }
+
+        void callSyncTeXToPDF(line, character, filePath, pdfFile, indicatorType).then( (record) => {
             if (pdfFile) {
                 void lw.viewer.locate(pdfFile, record)
             }
         })
+
     }
 }
 
@@ -200,12 +285,21 @@ function toPDF(args?: {line: number, filePath: string}, forcedViewer: 'auto' | '
  * @param col - The character position (column) in the line.
  * @param filePath - The path of the TeX file.
  * @param pdfFile - The path of the PDF file.
- * @returns A promise resolving to a SyncTeXRecordToPDF object.
+ * @param indicatorType - The type of the SyncTex indicator.
+ * @returns A promise resolving to a SyncTeXRecordToPDF object or a SyncTeXRecordToPDF[] object.
  */
-function callSyncTeXToPDF(line: number, col: number, filePath: string, pdfFile: string): Thenable<SyncTeXRecordToPDF> {
+function callSyncTeXToPDF(line: number, col: number, filePath: string, pdfFile: string, indicatorType: string): Thenable<SyncTeXRecordToPDF>;
+function callSyncTeXToPDF(line: number, col: number, filePath: string, pdfFile: string, indicatorType: string): Thenable<SyncTeXRecordToPDFAll[]>;
+function callSyncTeXToPDF(line: number, col: number, filePath: string, pdfFile: string, indicatorType: string): Thenable<SyncTeXRecordToPDF> | Thenable<SyncTeXRecordToPDFAll[]>  {
     const configuration = vscode.workspace.getConfiguration('latex-workshop')
     const docker = configuration.get('docker.enabled')
-    const args = ['view', '-i', `${line}:${col + 1}:${docker ? path.basename(filePath): filePath}`, '-o', docker ? path.basename(pdfFile): pdfFile]
+
+    let args: string[]
+    if (indicatorType === 'range') {
+        args = ['view', '-i', `${line}:0:${docker ? path.basename(filePath): filePath}`, '-o', docker ? path.basename(pdfFile): pdfFile]
+    } else {
+        args = ['view', '-i', `${line}:${col + 1}:${docker ? path.basename(filePath): filePath}`, '-o', docker ? path.basename(pdfFile): pdfFile]
+    }
 
     let command = configuration.get('synctex.path') as string
     if (docker) {
@@ -236,15 +330,20 @@ function callSyncTeXToPDF(line: number, col: number, filePath: string, pdfFile:
         logger.logError(`(${logTag}) Forward SyncTeX failed.`, err, stderr)
     })
 
-    return new Promise( (resolve) => {
+    return new Promise<SyncTeXRecordToPDF | SyncTeXRecordToPDFAll[]>( (resolve) => {
         proc.on('exit', exitCode => {
             if (exitCode !== 0) {
                 logger.logError(`(${logTag}) Forward SyncTeX failed.`, exitCode, stderr)
             } else {
-                resolve(parseToPDF(stdout))
+                if (indicatorType === 'range') {
+                    resolve(parseToPDFList(stdout))
+                } else if (indicatorType === 'spot') {
+                    resolve(parseToPDF(stdout))
+                }
+                // indicatorType === 'disabled' will do nothing, return directly
             }
         })
-    })
+    }) as Thenable<SyncTeXRecordToPDF> | Thenable<SyncTeXRecordToPDFAll[]>
 }
 
 /**

src/preview/viewer.ts

@@ -4,7 +4,7 @@ import * as path from 'path'
 import * as os from 'os'
 import * as cs from 'cross-spawn'
 import { lw } from '../lw'
-import type { SyncTeXRecordToPDF, ViewerMode } from '../types'
+import type { SyncTeXRecordToPDF, SyncTeXRecordToPDFAll, ViewerMode } from '../types'
 import * as manager from './viewer/pdfviewermanager'
 import { populate } from './viewer/pdfviewerpanel'
 
@@ -392,7 +392,7 @@ function getParams(): PdfViewerParams {
  * @param pdfFile The path of a PDF file.
  * @param record The position to be revealed.
  */
-async function locate(pdfFile: string, record: SyncTeXRecordToPDF): Promise<void> {
+async function locate(pdfFile: string, record: SyncTeXRecordToPDF | SyncTeXRecordToPDFAll[]): Promise<void> {
     const pdfUri = vscode.Uri.file(pdfFile)
     let clientSet = manager.getClients(pdfUri)
     if (clientSet === undefined || clientSet.size === 0) {
@@ -407,8 +407,7 @@ async function locate(pdfFile: string, record: SyncTeXRecordToPDF): Promise<void
     const needDelay = showInvisibleWebviewPanel(pdfUri)
     for (const client of clientSet) {
         setTimeout(() => {
-            const indicator = vscode.workspace.getConfiguration('latex-workshop').get('synctex.indicator.enabled') as boolean
-            client.send({type: 'synctex', data: {...record, indicator}})
+            client.send({type: 'synctex', data: record})
         }, needDelay ? 200 : 0)
         logger.log(`Try to synctex ${pdfFile}`)
     }

src/types.ts

@@ -108,6 +108,13 @@ export type SyncTeXRecordToTeX = {
     column: number
 }
 
+export type SyncTeXRecordToPDFAll = SyncTeXRecordToPDF & {
+    h: number;
+    v: number;
+    W: number;
+    H: number;
+}
+
 export interface LaTeXLinter {
     readonly linterDiagnostics: vscode.DiagnosticCollection,
     getName(): string,

types/latex-workshop-protocol-types/index.d.ts

@@ -1,13 +1,23 @@
+
+type SynctexData = {
+    page: number;
+    x: number;
+    y: number;
+    indicator: boolean;
+}
+
+type SynctexRangeData = SynctexData & {
+    h: number;
+    v: number;
+    W: number;
+    H: number;
+}
+
 export type ServerResponse = {
     type: 'refresh'
 } | {
     type: 'synctex',
-    data: {
-        page: number,
-        x: number,
-        y: number,
-        indicator: boolean
-    }
+    data: SynctexData | SynctexRangeData[]
 } | {
     type: 'reload'
 }

viewer/latexworkshop.css

@@ -54,6 +54,23 @@ html[dir='rtl'] .findbar {
     transform: translate(-50%, -50%);
 }
 
+@keyframes synctex-indicator-fadeOut {
+    0% {
+      background-color: rgba(0, 0, 255, 0.4);
+    }
+    100% {
+      background-color: rgba(0, 0, 255, 0);
+    }
+}
+
+.synctex-indicator-rect {
+  position: absolute;
+  z-index: 100000;
+  background-color: rgba(0, 0, 255, 0.5);
+  pointer-events: none;
+  animation: synctex-indicator-fadeOut 2s forwards;
+}
+
 #synctex-indicator.show {
     transition: none;
     opacity: 0.8;