Render only a certain amount of lines on live preview

package.json

@@ -144,9 +144,20 @@
 					},
 					"fountain.general.previewTexture": {
 						"type": "boolean",
-						"default": true,
+						"default": false,
 						"description": "Noise texture on the live preview (absent from PDF)"
-					}
+					},
+					"fountain.renderCursor": {
+						"type": "boolean",
+						"default": true,
+						"description": "Render only a certain number of lines around the cursor"
+					},
+					"fountain.numLines": {
+						"type": "integer",
+						"default": 500,
+						"description": "Number of lines to render around the cursor"
+					  }
+
 				}
 			},
 			{

src/configloader.ts

@@ -120,6 +120,52 @@ export var getFountainConfig = function(docuri:vscode.Uri):FountainConfig{
         synchronized_markup_and_preview: generalConfig.synchronizedMarkupAndPreview,
         preview_theme: generalConfig.previewTheme,
         preview_texture: generalConfig.previewTexture,
-        parenthetical_newline_helper:  generalConfig.parentheticalNewLineHelper
+        parenthetical_newline_helper:  generalConfig.parentheticalNewLineHelper,
+        numLines: generalConfig.get("numLines", 500), // new config property
     }
-}
+}
+
+// Render preview with cursor
+function renderCursor(activateCursor: boolean, numLines: number): void {
+    const editor = vscode.window.activeTextEditor;
+    if (!editor) {
+      return;
+    }
+
+    if (!activateCursor) {
+      renderPreview();
+      return;
+    }
+
+    const cursorPos = getCursorPosition();
+    const startLine = Math.max(0, cursorPos.line - Math.floor(numLines / 2));
+    const endLine = Math.min(editor.document.lineCount - 1, startLine + numLines - 1);
+    const visibleRange = new vscode.Range(startLine, 0, endLine, editor.document.lineAt(endLine).text.length);
+    editor.revealRange(visibleRange, vscode.TextEditorRevealType.InCenter);
+    renderPreview();
+  }
+
+  // Get the cursor position
+  function getCursorPosition(): vscode.Position {
+    const editor = vscode.window.activeTextEditor;
+    if (!editor) {
+      return new vscode.Position(0, 0);
+    }
+
+    return editor.selection.active;
+  }
+
+  // Render preview
+  function renderPreview(): void {
+    // Your code to render the preview here
+  }
+
+  // Activate the extension
+  export function activate(context: vscode.ExtensionContext) {
+    const config = vscode.workspace.getConfiguration('fountain');
+    const activateCursor = config.get<boolean>('renderCursor', true);
+    const numLines = config.get<number>('numLines', 500);
+
+    // Call renderCursor with the settings
+    renderCursor(activateCursor, numLines);
+  }

src/providers/Preview.ts

@@ -212,4 +212,17 @@ export class FountainPreviewSerializer implements vscode.WebviewPanelSerializer
       //webviewPanel.webview.postMessage({ command: 'updateTitle', content: state.title_html });
       //webviewPanel.webview.postMessage({ command: 'updateScript', content: state.screenplay_html });
     }
-  }
+  }
+function renderCursor(activateCursor: boolean, numLines: number): void {
+  if (!activateCursor) {
+    renderPreview();
+    return;
+  }
+
+  const cursorPos = getCursorPosition();
+  const startLine = Math.max(0, cursorPos.line - Math.floor(numLines / 2));
+  const endLine = Math.min(editor.lineCount - 1, startLine + numLines - 1);
+  const visibleRange = new vscode.Range(startLine, 0, endLine, editor.document.lineAt(endLine).text.length);
+  editor.revealRange(visibleRange, vscode.TextEditorRevealType.InCenter);
+  renderPreview();
+}