feat: add line height attribute to text element (#6360)

* feat: add line height attribute to text element

* lint

* update line height when redrawing text bounding box

* fix tests

* retain line height when pasting styles

* fix test

* create a util for calculating ling height using old algo

* update line height when resizing multiple text elements

* make line height backward compatible

* udpate line height for older element when font size updated

* remove logs

* Add specs

* lint

* review fixes

* simplify by changing `lineHeight` from px to unitless

* make param non-optional

* update comment

* fix: jumping text due to font size being calculated incorrectly

* update line height when font family is updated

* lint

* Add spec

* more specs

* rename to getDefaultLineHeight

* fix getting lineHeight for potentially undefined fontFamily

* reduce duplication

* fix fallback

* refactor and comment tweaks

* fix

---------

Co-authored-by: dwelle <luzar.david@gmail.com>

src/actions/actionBoundText.tsx

@@ -45,6 +45,7 @@ export const actionUnbindText = register({
         const { width, height } = measureText(
           boundTextElement.originalText,
           getFontString(boundTextElement),
+          boundTextElement.lineHeight,
         );
         const originalContainerHeight = getOriginalContainerHeightFromCache(
           element.id,

src/actions/actionProperties.tsx

@@ -54,6 +54,7 @@ import { mutateElement, newElementWith } from "../element/mutateElement";
 import {
   getBoundTextElement,
   getContainerElement,
+  getDefaultLineHeight,
 } from "../element/textElement";
 import {
   isBoundToContainer,
@@ -637,6 +638,7 @@ export const actionChangeFontFamily = register({
               oldElement,
               {
                 fontFamily: value,
+                lineHeight: getDefaultLineHeight(value),
               },
             );
             redrawTextBoundingBox(newElement, getContainerElement(oldElement));

src/actions/actionStyles.ts

@@ -12,7 +12,10 @@ import {
   DEFAULT_FONT_FAMILY,
   DEFAULT_TEXT_ALIGN,
 } from "../constants";
-import { getBoundTextElement } from "../element/textElement";
+import {
+  getBoundTextElement,
+  getDefaultLineHeight,
+} from "../element/textElement";
 import {
   hasBoundTextElement,
   canApplyRoundnessTypeToElement,
@@ -92,12 +95,18 @@ export const actionPasteStyles = register({
           });
 
           if (isTextElement(newElement)) {
+            const fontSize =
+              elementStylesToCopyFrom?.fontSize || DEFAULT_FONT_SIZE;
+            const fontFamily =
+              elementStylesToCopyFrom?.fontFamily || DEFAULT_FONT_FAMILY;
             newElement = newElementWith(newElement, {
-              fontSize: elementStylesToCopyFrom?.fontSize || DEFAULT_FONT_SIZE,
-              fontFamily:
-                elementStylesToCopyFrom?.fontFamily || DEFAULT_FONT_FAMILY,
+              fontSize,
+              fontFamily,
               textAlign:
                 elementStylesToCopyFrom?.textAlign || DEFAULT_TEXT_ALIGN,
+              lineHeight:
+                elementStylesToCopyFrom.lineHeight ||
+                getDefaultLineHeight(fontFamily),
             });
             let container = null;
             if (newElement.containerId) {

src/components/App.tsx

@@ -260,13 +260,14 @@ import throttle from "lodash.throttle";
 import { fileOpen, FileSystemHandle } from "../data/filesystem";
 import {
   bindTextToShapeAfterDuplication,
-  getApproxLineHeight,
   getApproxMinLineHeight,
   getApproxMinLineWidth,
   getBoundTextElement,
   getContainerCenter,
   getContainerDims,
   getContainerElement,
+  getDefaultLineHeight,
+  getLineHeightInPx,
   getTextBindableContainerAtPosition,
   isMeasureTextSupported,
   isValidTextContainer,
@@ -1731,12 +1732,14 @@ class App extends React.Component<AppProps, AppState> {
       (acc: ExcalidrawTextElement[], line, idx) => {
         const text = line.trim();
 
+        const lineHeight = getDefaultLineHeight(textElementProps.fontFamily);
         if (text.length) {
           const element = newTextElement({
             ...textElementProps,
             x,
             y: currentY,
             text,
+            lineHeight,
           });
           acc.push(element);
           currentY += element.height + LINE_GAP;
@@ -1745,14 +1748,9 @@ class App extends React.Component<AppProps, AppState> {
           // add paragraph only if previous line was not empty, IOW don't add
           // more than one empty line
           if (prevLine) {
-            const defaultLineHeight = getApproxLineHeight(
-              getFontString({
-                fontSize: textElementProps.fontSize,
-                fontFamily: textElementProps.fontFamily,
-              }),
-            );
-
-            currentY += defaultLineHeight + LINE_GAP;
+            currentY +=
+              getLineHeightInPx(textElementProps.fontSize, lineHeight) +
+              LINE_GAP;
           }
         }
 
@@ -2607,6 +2605,13 @@ class App extends React.Component<AppProps, AppState> {
       existingTextElement = this.getTextElementAtPosition(sceneX, sceneY);
     }
 
+    const fontFamily =
+      existingTextElement?.fontFamily || this.state.currentItemFontFamily;
+
+    const lineHeight =
+      existingTextElement?.lineHeight || getDefaultLineHeight(fontFamily);
+    const fontSize = this.state.currentItemFontSize;
+
     if (
       !existingTextElement &&
       shouldBindToContainer &&
@@ -2614,11 +2619,14 @@ class App extends React.Component<AppProps, AppState> {
       !isArrowElement(container)
     ) {
       const fontString = {
-        fontSize: this.state.currentItemFontSize,
-        fontFamily: this.state.currentItemFontFamily,
+        fontSize,
+        fontFamily,
       };
-      const minWidth = getApproxMinLineWidth(getFontString(fontString));
-      const minHeight = getApproxMinLineHeight(getFontString(fontString));
+      const minWidth = getApproxMinLineWidth(
+        getFontString(fontString),
+        lineHeight,
+      );
+      const minHeight = getApproxMinLineHeight(fontSize, lineHeight);
       const containerDims = getContainerDims(container);
       const newHeight = Math.max(containerDims.height, minHeight);
       const newWidth = Math.max(containerDims.width, minWidth);
@@ -2652,8 +2660,8 @@ class App extends React.Component<AppProps, AppState> {
           opacity: this.state.currentItemOpacity,
           roundness: null,
           text: "",
-          fontSize: this.state.currentItemFontSize,
-          fontFamily: this.state.currentItemFontFamily,
+          fontSize,
+          fontFamily,
           textAlign: parentCenterPosition
             ? "center"
             : this.state.currentItemTextAlign,
@@ -2663,6 +2671,7 @@ class App extends React.Component<AppProps, AppState> {
           containerId: shouldBindToContainer ? container?.id : undefined,
           groupIds: container?.groupIds ?? [],
           locked: false,
+          lineHeight,
         });
 
     if (!existingTextElement && shouldBindToContainer && container) {

src/data/restore.ts

@@ -35,6 +35,7 @@ import { getUpdatedTimestamp, updateActiveTool } from "../utils";
 import { arrayToMap } from "../utils";
 import oc from "open-color";
 import { MarkOptional, Mutable } from "../utility-types";
+import { detectLineHeight, getDefaultLineHeight } from "../element/textElement";
 
 type RestoredAppState = Omit<
   AppState,
@@ -165,17 +166,32 @@ const restoreElement = (
         const [fontPx, _fontFamily]: [string, string] = (
           element as any
         ).font.split(" ");
-        fontSize = parseInt(fontPx, 10);
+        fontSize = parseFloat(fontPx);
         fontFamily = getFontFamilyByName(_fontFamily);
       }
+      const text = element.text ?? "";
+
       element = restoreElementWithProperties(element, {
         fontSize,
         fontFamily,
-        text: element.text ?? "",
+        text,
         textAlign: element.textAlign || DEFAULT_TEXT_ALIGN,
         verticalAlign: element.verticalAlign || DEFAULT_VERTICAL_ALIGN,
         containerId: element.containerId ?? null,
-        originalText: element.originalText || element.text,
+        originalText: element.originalText || text,
+        // line-height might not be specified either when creating elements
+        // programmatically, or when importing old diagrams.
+        // For the latter we want to detect the original line height which
+        // will likely differ from our per-font fixed line height we now use,
+        // to maintain backward compatibility.
+        lineHeight:
+          element.lineHeight ||
+          (element.height
+            ? // detect line-height from current element height and font-size
+              detectLineHeight(element)
+            : // no element height likely means programmatic use, so default
+              // to a fixed line height
+              getDefaultLineHeight(element.fontFamily)),
       });
 
       if (refreshDimensions) {

src/element/newElement.ts

@@ -29,6 +29,7 @@ import {
   normalizeText,
   wrapText,
   getMaxContainerWidth,
+  getDefaultLineHeight,
 } from "./textElement";
 import { VERTICAL_ALIGN } from "../constants";
 import { isArrowElement } from "./typeChecks";
@@ -137,10 +138,12 @@ export const newTextElement = (
     textAlign: TextAlign;
     verticalAlign: VerticalAlign;
     containerId?: ExcalidrawTextContainer["id"];
+    lineHeight?: ExcalidrawTextElement["lineHeight"];
   } & ElementConstructorOpts,
 ): NonDeleted<ExcalidrawTextElement> => {
+  const lineHeight = opts.lineHeight || getDefaultLineHeight(opts.fontFamily);
   const text = normalizeText(opts.text);
-  const metrics = measureText(text, getFontString(opts));
+  const metrics = measureText(text, getFontString(opts), lineHeight);
   const offsets = getTextElementPositionOffsets(opts, metrics);
   const textElement = newElementWith(
     {
@@ -156,6 +159,7 @@ export const newTextElement = (
       height: metrics.height,
       containerId: opts.containerId || null,
       originalText: text,
+      lineHeight,
     },
     {},
   );
@@ -176,6 +180,7 @@ const getAdjustedDimensions = (
   const { width: nextWidth, height: nextHeight } = measureText(
     nextText,
     getFontString(element),
+    element.lineHeight,
   );
   const { textAlign, verticalAlign } = element;
   let x: number;
@@ -185,7 +190,11 @@ const getAdjustedDimensions = (
     verticalAlign === VERTICAL_ALIGN.MIDDLE &&
     !element.containerId
   ) {
-    const prevMetrics = measureText(element.text, getFontString(element));
+    const prevMetrics = measureText(
+      element.text,
+      getFontString(element),
+      element.lineHeight,
+    );
     const offsets = getTextElementPositionOffsets(element, {
       width: nextWidth - prevMetrics.width,
       height: nextHeight - prevMetrics.height,

src/element/resizeElements.ts

@@ -39,13 +39,13 @@ import {
 import { Point, PointerDownState } from "../types";
 import Scene from "../scene/Scene";
 import {
-  getApproxMinLineHeight,
   getApproxMinLineWidth,
   getBoundTextElement,
   getBoundTextElementId,
   getContainerElement,
   handleBindTextResize,
   getMaxContainerWidth,
+  getApproxMinLineHeight,
 } from "./textElement";
 
 export const normalizeAngle = (angle: number): number => {
@@ -360,7 +360,7 @@ export const resizeSingleElement = (
   let scaleX = atStartBoundsWidth / boundsCurrentWidth;
   let scaleY = atStartBoundsHeight / boundsCurrentHeight;
 
-  let boundTextFont: { fontSize?: number } = {};
+  let boundTextFontSize: number | null = null;
   const boundTextElement = getBoundTextElement(element);
 
   if (transformHandleDirection.includes("e")) {
@@ -410,9 +410,7 @@ export const resizeSingleElement = (
       boundTextElement.id,
     ) as typeof boundTextElement | undefined;
     if (stateOfBoundTextElementAtResize) {
-      boundTextFont = {
-        fontSize: stateOfBoundTextElementAtResize.fontSize,
-      };
+      boundTextFontSize = stateOfBoundTextElementAtResize.fontSize;
     }
     if (shouldMaintainAspectRatio) {
       const updatedElement = {
@@ -428,12 +426,16 @@ export const resizeSingleElement = (
       if (nextFontSize === null) {
         return;
       }
-      boundTextFont = {
-        fontSize: nextFontSize,
-      };
+      boundTextFontSize = nextFontSize;
     } else {
-      const minWidth = getApproxMinLineWidth(getFontString(boundTextElement));
-      const minHeight = getApproxMinLineHeight(getFontString(boundTextElement));
+      const minWidth = getApproxMinLineWidth(
+        getFontString(boundTextElement),
+        boundTextElement.lineHeight,
+      );
+      const minHeight = getApproxMinLineHeight(
+        boundTextElement.fontSize,
+        boundTextElement.lineHeight,
+      );
       eleNewWidth = Math.ceil(Math.max(eleNewWidth, minWidth));
       eleNewHeight = Math.ceil(Math.max(eleNewHeight, minHeight));
     }
@@ -566,8 +568,10 @@ export const resizeSingleElement = (
     });
 
     mutateElement(element, resizedElement);
-    if (boundTextElement && boundTextFont) {
-      mutateElement(boundTextElement, { fontSize: boundTextFont.fontSize });
+    if (boundTextElement && boundTextFontSize != null) {
+      mutateElement(boundTextElement, {
+        fontSize: boundTextFontSize,
+      });
     }
     handleBindTextResize(element, transformHandleDirection);
   }

src/element/textElement.test.ts

@@ -1,4 +1,4 @@
-import { BOUND_TEXT_PADDING } from "../constants";
+import { BOUND_TEXT_PADDING, FONT_FAMILY } from "../constants";
 import { API } from "../tests/helpers/api";
 import {
   computeContainerDimensionForBoundText,
@@ -6,6 +6,9 @@ import {
   getMaxContainerWidth,
   getMaxContainerHeight,
   wrapText,
+  detectLineHeight,
+  getLineHeightInPx,
+  getDefaultLineHeight,
 } from "./textElement";
 import { FontString } from "./types";
 
@@ -40,9 +43,7 @@ describe("Test wrapText", () => {
       {
         desc: "break all words when width of each word is less than container width",
         width: 80,
-        res: `Hello 
-whats 
-up`,
+        res: `Hello \nwhats \nup`,
       },
       {
         desc: "break all characters when width of each character is less than container width",
@@ -64,8 +65,7 @@ p`,
         desc: "break words as per the width",
 
         width: 140,
-        res: `Hello whats 
-up`,
+        res: `Hello whats \nup`,
       },
       {
         desc: "fit the container",
@@ -95,9 +95,7 @@ whats up`;
       {
         desc: "break all words when width of each word is less than container width",
         width: 80,
-        res: `Hello
-whats 
-up`,
+        res: `Hello\nwhats \nup`,
       },
       {
         desc: "break all characters when width of each character is less than container width",
@@ -143,11 +141,7 @@ whats up`,
       {
         desc: "fit characters of long string as per container width",
         width: 170,
-        res: `hellolongtextth
-isiswhatsupwith
-youIamtypingggg
-gandtypinggg 
-break it now`,
+        res: `hellolongtextth\nisiswhatsupwith\nyouIamtypingggg\ngandtypinggg \nbreak it now`,
       },
 
       {
@@ -166,8 +160,7 @@ now`,
         desc: "fit the long text when container width is greater than text length and move the rest to next line",
 
         width: 600,
-        res: `hellolongtextthisiswhatsupwithyouIamtypingggggandtypinggg 
-break it now`,
+        res: `hellolongtextthisiswhatsupwithyouIamtypingggggandtypinggg \nbreak it now`,
       },
     ].forEach((data) => {
       it(`should ${data.desc}`, () => {
@@ -181,8 +174,7 @@ break it now`,
     const text = "Hello Excalidraw";
     // Length of "Excalidraw" is 100 and exacty equal to max width
     const res = wrapText(text, font, 100);
-    expect(res).toEqual(`Hello 
-Excalidraw`);
+    expect(res).toEqual(`Hello \nExcalidraw`);
   });
 
   it("should return the text as is if max width is invalid", () => {
@@ -312,3 +304,35 @@ describe("Test measureText", () => {
     });
   });
 });
+
+const textElement = API.createElement({
+  type: "text",
+  text: "Excalidraw is a\nvirtual \nopensource \nwhiteboard for \nsketching \nhand-drawn like\ndiagrams",
+  fontSize: 20,
+  fontFamily: 1,
+  height: 175,
+});
+
+describe("Test detectLineHeight", () => {
+  it("should return correct line height", () => {
+    expect(detectLineHeight(textElement)).toBe(1.25);
+  });
+});
+
+describe("Test getLineHeightInPx", () => {
+  it("should return correct line height", () => {
+    expect(
+      getLineHeightInPx(textElement.fontSize, textElement.lineHeight),
+    ).toBe(25);
+  });
+});
+
+describe("Test getDefaultLineHeight", () => {
+  it("should return line height using default font family when not passed", () => {
+    //@ts-ignore
+    expect(getDefaultLineHeight()).toBe(1.25);
+  });
+  it("should return correct line height", () => {
+    expect(getDefaultLineHeight(FONT_FAMILY.Cascadia)).toBe(1.2);
+  });
+});

src/element/textElement.ts

@@ -4,6 +4,7 @@ import {
   ExcalidrawTextContainer,
   ExcalidrawTextElement,
   ExcalidrawTextElementWithContainer,
+  FontFamilyValues,
   FontString,
   NonDeletedExcalidrawElement,
 } from "./types";
@@ -12,6 +13,7 @@ import {
   BOUND_TEXT_PADDING,
   DEFAULT_FONT_FAMILY,
   DEFAULT_FONT_SIZE,
+  FONT_FAMILY,
   TEXT_ALIGN,
   VERTICAL_ALIGN,
 } from "../constants";
@@ -41,12 +43,15 @@ export const normalizeText = (text: string) => {
   );
 };
 
+export const splitIntoLines = (text: string) => {
+  return normalizeText(text).split("\n");
+};
+
 export const redrawTextBoundingBox = (
   textElement: ExcalidrawTextElement,
   container: ExcalidrawElement | null,
 ) => {
   let maxWidth = undefined;
-
   const boundTextUpdates = {
     x: textElement.x,
     y: textElement.y,
@@ -68,6 +73,7 @@ export const redrawTextBoundingBox = (
   const metrics = measureText(
     boundTextUpdates.text,
     getFontString(textElement),
+    textElement.lineHeight,
   );
 
   boundTextUpdates.width = metrics.width;
@@ -185,7 +191,11 @@ export const handleBindTextResize = (
           maxWidth,
         );
       }
-      const dimensions = measureText(text, getFontString(textElement));
+      const dimensions = measureText(
+        text,
+        getFontString(textElement),
+        textElement.lineHeight,
+      );
       nextHeight = dimensions.height;
       nextWidth = dimensions.width;
     }
@@ -261,32 +271,52 @@ const computeBoundTextPosition = (
 
 // https://github.com/grassator/canvas-text-editor/blob/master/lib/FontMetrics.js
 
-export const measureText = (text: string, font: FontString) => {
+export const measureText = (
+  text: string,
+  font: FontString,
+  lineHeight: ExcalidrawTextElement["lineHeight"],
+) => {
   text = text
     .split("\n")
     // replace empty lines with single space because leading/trailing empty
     // lines would be stripped from computation
     .map((x) => x || " ")
     .join("\n");
-
-  const height = getTextHeight(text, font);
+  const fontSize = parseFloat(font);
+  const height = getTextHeight(text, fontSize, lineHeight);
   const width = getTextWidth(text, font);
 
   return { width, height };
 };
 
-const DUMMY_TEXT = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789".toLocaleUpperCase();
-const cacheApproxLineHeight: { [key: FontString]: number } = {};
-
-export const getApproxLineHeight = (font: FontString) => {
-  if (cacheApproxLineHeight[font]) {
-    return cacheApproxLineHeight[font];
-  }
-  const fontSize = parseInt(font);
+/**
+ * To get unitless line-height (if unknown) we can calculate it by dividing
+ * height-per-line by fontSize.
+ */
+export const detectLineHeight = (textElement: ExcalidrawTextElement) => {
+  const lineCount = splitIntoLines(textElement.text).length;
+  return (textElement.height /
+    lineCount /
+    textElement.fontSize) as ExcalidrawTextElement["lineHeight"];
+};
+
+/**
+ * We calculate the line height from the font size and the unitless line height,
+ * aligning with the W3C spec.
+ */
+export const getLineHeightInPx = (
+  fontSize: ExcalidrawTextElement["fontSize"],
+  lineHeight: ExcalidrawTextElement["lineHeight"],
+) => {
+  return fontSize * lineHeight;
+};
 
-  // Calculate line height relative to font size
-  cacheApproxLineHeight[font] = fontSize * 1.2;
-  return cacheApproxLineHeight[font];
+// FIXME rename to getApproxMinContainerHeight
+export const getApproxMinLineHeight = (
+  fontSize: ExcalidrawTextElement["fontSize"],
+  lineHeight: ExcalidrawTextElement["lineHeight"],
+) => {
+  return getLineHeightInPx(fontSize, lineHeight) + BOUND_TEXT_PADDING * 2;
 };
 
 let canvas: HTMLCanvasElement | undefined;
@@ -309,7 +339,7 @@ const getLineWidth = (text: string, font: FontString) => {
 };
 
 export const getTextWidth = (text: string, font: FontString) => {
-  const lines = text.replace(/\r\n?/g, "\n").split("\n");
+  const lines = splitIntoLines(text);
   let width = 0;
   lines.forEach((line) => {
     width = Math.max(width, getLineWidth(line, font));
@@ -317,10 +347,13 @@ export const getTextWidth = (text: string, font: FontString) => {
   return width;
 };
 
-export const getTextHeight = (text: string, font: FontString) => {
-  const lines = text.replace(/\r\n?/g, "\n").split("\n");
-  const lineHeight = getApproxLineHeight(font);
-  return lineHeight * lines.length;
+export const getTextHeight = (
+  text: string,
+  fontSize: number,
+  lineHeight: ExcalidrawTextElement["lineHeight"],
+) => {
+  const lineCount = splitIntoLines(text).length;
+  return getLineHeightInPx(fontSize, lineHeight) * lineCount;
 };
 
 export const wrapText = (text: string, font: FontString, maxWidth: number) => {
@@ -468,21 +501,23 @@ export const charWidth = (() => {
   };
 })();
 
-export const getApproxMinLineWidth = (font: FontString) => {
+const DUMMY_TEXT = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789".toLocaleUpperCase();
+
+// FIXME rename to getApproxMinContainerWidth
+export const getApproxMinLineWidth = (
+  font: FontString,
+  lineHeight: ExcalidrawTextElement["lineHeight"],
+) => {
   const maxCharWidth = getMaxCharWidth(font);
   if (maxCharWidth === 0) {
     return (
-      measureText(DUMMY_TEXT.split("").join("\n"), font).width +
+      measureText(DUMMY_TEXT.split("").join("\n"), font, lineHeight).width +
       BOUND_TEXT_PADDING * 2
     );
   }
   return maxCharWidth + BOUND_TEXT_PADDING * 2;
 };
 
-export const getApproxMinLineHeight = (font: FontString) => {
-  return getApproxLineHeight(font) + BOUND_TEXT_PADDING * 2;
-};
-
 export const getMinCharWidth = (font: FontString) => {
   const cache = charWidth.getCache(font);
   if (!cache) {
@@ -828,3 +863,32 @@ export const isMeasureTextSupported = () => {
   );
   return width > 0;
 };
+
+/**
+ * Unitless line height
+ *
+ * In previous versions we used `normal` line height, which browsers interpret
+ * differently, and based on font-family and font-size.
+ *
+ * To make line heights consistent across browsers we hardcode the values for
+ * each of our fonts based on most common average line-heights.
+ * See https://github.com/excalidraw/excalidraw/pull/6360#issuecomment-1477635971
+ * where the values come from.
+ */
+const DEFAULT_LINE_HEIGHT = {
+  // ~1.25 is the average for Virgil in WebKit and Blink.
+  // Gecko (FF) uses ~1.28.
+  [FONT_FAMILY.Virgil]: 1.25 as ExcalidrawTextElement["lineHeight"],
+  // ~1.15 is the average for Virgil in WebKit and Blink.
+  // Gecko if all over the place.
+  [FONT_FAMILY.Helvetica]: 1.15 as ExcalidrawTextElement["lineHeight"],
+  // ~1.2 is the average for Virgil in WebKit and Blink, and kinda Gecko too
+  [FONT_FAMILY.Cascadia]: 1.2 as ExcalidrawTextElement["lineHeight"],
+};
+
+export const getDefaultLineHeight = (fontFamily: FontFamilyValues) => {
+  if (fontFamily) {
+    return DEFAULT_LINE_HEIGHT[fontFamily];
+  }
+  return DEFAULT_LINE_HEIGHT[DEFAULT_FONT_FAMILY];
+};

src/element/textWysiwyg.test.tsx

@@ -783,7 +783,7 @@ describe("textWysiwyg", () => {
         rectangle.y + h.elements[0].height / 2 - text.height / 2,
       );
       expect(text.x).toBe(25);
-      expect(text.height).toBe(48);
+      expect(text.height).toBe(50);
       expect(text.width).toBe(60);
 
       // Edit and text by removing second line and it should
@@ -810,7 +810,7 @@ describe("textWysiwyg", () => {
 
       expect(text.text).toBe("Hello");
       expect(text.originalText).toBe("Hello");
-      expect(text.height).toBe(24);
+      expect(text.height).toBe(25);
       expect(text.width).toBe(50);
       expect(text.y).toBe(
         rectangle.y + h.elements[0].height / 2 - text.height / 2,
@@ -903,7 +903,7 @@ describe("textWysiwyg", () => {
       expect([h.elements[1].x, h.elements[1].y]).toMatchInlineSnapshot(`
         Array [
           85,
-          5,
+          4.5,
         ]
       `);
 
@@ -929,7 +929,7 @@ describe("textWysiwyg", () => {
       expect([h.elements[1].x, h.elements[1].y]).toMatchInlineSnapshot(`
         Array [
           15,
-          66,
+          65,
         ]
       `);
 
@@ -1067,9 +1067,9 @@ describe("textWysiwyg", () => {
       mouse.moveTo(rectangle.x + 100, rectangle.y + 50);
       mouse.up(rectangle.x + 100, rectangle.y + 50);
       expect(rectangle.x).toBe(80);
-      expect(rectangle.y).toBe(-35);
+      expect(rectangle.y).toBe(-40);
       expect(text.x).toBe(85);
-      expect(text.y).toBe(-30);
+      expect(text.y).toBe(-35);
 
       Keyboard.withModifierKeys({ ctrl: true }, () => {
         Keyboard.keyPress(KEYS.Z);
@@ -1112,7 +1112,7 @@ describe("textWysiwyg", () => {
         target: { value: "Online whiteboard collaboration made easy" },
       });
       editor.blur();
-      expect(rectangle.height).toBe(178);
+      expect(rectangle.height).toBe(185);
       mouse.select(rectangle);
       fireEvent.contextMenu(GlobalTestState.canvas, {
         button: 2,
@@ -1186,6 +1186,41 @@ describe("textWysiwyg", () => {
       );
     });
 
+    it("should update line height when font family updated", async () => {
+      Keyboard.keyPress(KEYS.ENTER);
+      expect(getOriginalContainerHeightFromCache(rectangle.id)).toBe(75);
+
+      const editor = document.querySelector(
+        ".excalidraw-textEditorContainer > textarea",
+      ) as HTMLTextAreaElement;
+
+      await new Promise((r) => setTimeout(r, 0));
+      fireEvent.change(editor, { target: { value: "Hello World!" } });
+      editor.blur();
+      expect(
+        (h.elements[1] as ExcalidrawTextElementWithContainer).lineHeight,
+      ).toEqual(1.25);
+
+      mouse.select(rectangle);
+      Keyboard.keyPress(KEYS.ENTER);
+
+      fireEvent.click(screen.getByTitle(/code/i));
+      expect(
+        (h.elements[1] as ExcalidrawTextElementWithContainer).fontFamily,
+      ).toEqual(FONT_FAMILY.Cascadia);
+      expect(
+        (h.elements[1] as ExcalidrawTextElementWithContainer).lineHeight,
+      ).toEqual(1.2);
+
+      fireEvent.click(screen.getByTitle(/normal/i));
+      expect(
+        (h.elements[1] as ExcalidrawTextElementWithContainer).fontFamily,
+      ).toEqual(FONT_FAMILY.Helvetica);
+      expect(
+        (h.elements[1] as ExcalidrawTextElementWithContainer).lineHeight,
+      ).toEqual(1.15);
+    });
+
     describe("should align correctly", () => {
       let editor: HTMLTextAreaElement;
 
@@ -1245,7 +1280,7 @@ describe("textWysiwyg", () => {
         expect([h.elements[1].x, h.elements[1].y]).toMatchInlineSnapshot(`
           Array [
             15,
-            45.5,
+            45,
           ]
         `);
       });
@@ -1257,7 +1292,7 @@ describe("textWysiwyg", () => {
         expect([h.elements[1].x, h.elements[1].y]).toMatchInlineSnapshot(`
           Array [
             30,
-            45.5,
+            45,
           ]
         `);
       });
@@ -1269,7 +1304,7 @@ describe("textWysiwyg", () => {
         expect([h.elements[1].x, h.elements[1].y]).toMatchInlineSnapshot(`
           Array [
             45,
-            45.5,
+            45,
           ]
         `);
       });
@@ -1281,7 +1316,7 @@ describe("textWysiwyg", () => {
         expect([h.elements[1].x, h.elements[1].y]).toMatchInlineSnapshot(`
           Array [
             15,
-            66,
+            65,
           ]
         `);
       });
@@ -1292,7 +1327,7 @@ describe("textWysiwyg", () => {
         expect([h.elements[1].x, h.elements[1].y]).toMatchInlineSnapshot(`
           Array [
             30,
-            66,
+            65,
           ]
         `);
       });
@@ -1303,7 +1338,7 @@ describe("textWysiwyg", () => {
         expect([h.elements[1].x, h.elements[1].y]).toMatchInlineSnapshot(`
           Array [
             45,
-            66,
+            65,
           ]
         `);
       });
@@ -1333,7 +1368,7 @@ describe("textWysiwyg", () => {
 
       const textElement = h.elements[1] as ExcalidrawTextElement;
       expect(textElement.width).toBe(600);
-      expect(textElement.height).toBe(24);
+      expect(textElement.height).toBe(25);
       expect(textElement.textAlign).toBe(TEXT_ALIGN.LEFT);
       expect((textElement as ExcalidrawTextElement).text).toBe(
         "Excalidraw is an opensource virtual collaborative whiteboard",
@@ -1365,7 +1400,7 @@ describe("textWysiwyg", () => {
           ],
           fillStyle: "hachure",
           groupIds: [],
-          height: 34,
+          height: 35,
           isDeleted: false,
           link: null,
           locked: false,

src/element/textWysiwyg.tsx

@@ -22,7 +22,6 @@ import {
 import { AppState } from "../types";
 import { mutateElement } from "./mutateElement";
 import {
-  getApproxLineHeight,
   getBoundTextElementId,
   getContainerCoords,
   getContainerDims,
@@ -150,9 +149,7 @@ export const textWysiwyg = ({
       return;
     }
     const { textAlign, verticalAlign } = updatedTextElement;
-    const approxLineHeight = getApproxLineHeight(
-      getFontString(updatedTextElement),
-    );
+
     if (updatedTextElement && isTextElement(updatedTextElement)) {
       let coordX = updatedTextElement.x;
       let coordY = updatedTextElement.y;
@@ -213,7 +210,7 @@ export const textWysiwyg = ({
         if (!isArrowElement(container) && textElementHeight > maxHeight) {
           const diff = Math.min(
             textElementHeight - maxHeight,
-            approxLineHeight,
+            element.lineHeight,
           );
           mutateElement(container, { height: containerDims.height + diff });
           return;
@@ -226,7 +223,7 @@ export const textWysiwyg = ({
         ) {
           const diff = Math.min(
             maxHeight - textElementHeight,
-            approxLineHeight,
+            element.lineHeight,
           );
           mutateElement(container, { height: containerDims.height - diff });
         }
@@ -266,10 +263,6 @@ export const textWysiwyg = ({
         editable.selectionEnd = editable.value.length - diff;
       }
 
-      const lines = updatedTextElement.originalText.split("\n");
-      const lineHeight = updatedTextElement.containerId
-        ? approxLineHeight
-        : updatedTextElement.height / lines.length;
       if (!container) {
         maxWidth = (appState.width - 8 - viewportX) / appState.zoom.value;
         textElementWidth = Math.min(textElementWidth, maxWidth);
@@ -282,7 +275,7 @@ export const textWysiwyg = ({
       Object.assign(editable.style, {
         font: getFontString(updatedTextElement),
         // must be defined *after* font ¯\_(ツ)_/¯
-        lineHeight: `${lineHeight}px`,
+        lineHeight: element.lineHeight,
         width: `${textElementWidth}px`,
         height: `${textElementHeight}px`,
         left: `${viewportX}px`,
@@ -388,7 +381,11 @@ export const textWysiwyg = ({
           font,
           getMaxContainerWidth(container!),
         );
-        const { width, height } = measureText(wrappedText, font);
+        const { width, height } = measureText(
+          wrappedText,
+          font,
+          updatedTextElement.lineHeight,
+        );
         editable.style.width = `${width}px`;
         editable.style.height = `${height}px`;
       }

src/element/types.ts

@@ -135,6 +135,11 @@ export type ExcalidrawTextElement = _ExcalidrawElementBase &
     verticalAlign: VerticalAlign;
     containerId: ExcalidrawGenericElement["id"] | null;
     originalText: string;
+    /**
+     * Unitless line height (aligned to W3C). To get line height in px, multiply
+     *  with font size (using `getLineHeightInPx` helper).
+     */
+    lineHeight: number & { _brand: "unitlessLineHeight" };
   }>;
 
 export type ExcalidrawBindableElement =

src/renderer/renderElement.ts

@@ -40,10 +40,10 @@ import {
 } from "../constants";
 import { getStroke, StrokeOptions } from "perfect-freehand";
 import {
-  getApproxLineHeight,
   getBoundTextElement,
   getContainerCoords,
   getContainerElement,
+  getLineHeightInPx,
   getMaxContainerHeight,
   getMaxContainerWidth,
 } from "../element/textElement";
@@ -279,9 +279,7 @@ const drawElementOnCanvas = (
 
         // Canvas does not support multiline text by default
         const lines = element.text.replace(/\r\n?/g, "\n").split("\n");
-        const lineHeight = element.containerId
-          ? getApproxLineHeight(getFontString(element))
-          : element.height / lines.length;
+
         const horizontalOffset =
           element.textAlign === "center"
             ? element.width / 2
@@ -290,11 +288,16 @@ const drawElementOnCanvas = (
             : 0;
         context.textBaseline = "bottom";
 
+        const lineHeightPx = getLineHeightInPx(
+          element.fontSize,
+          element.lineHeight,
+        );
+
         for (let index = 0; index < lines.length; index++) {
           context.fillText(
             lines[index],
             horizontalOffset,
-            (index + 1) * lineHeight,
+            (index + 1) * lineHeightPx,
           );
         }
         context.restore();
@@ -1313,7 +1316,10 @@ export const renderElementToSvg = (
           }) rotate(${degree} ${cx} ${cy})`,
         );
         const lines = element.text.replace(/\r\n?/g, "\n").split("\n");
-        const lineHeight = element.height / lines.length;
+        const lineHeightPx = getLineHeightInPx(
+          element.fontSize,
+          element.lineHeight,
+        );
         const horizontalOffset =
           element.textAlign === "center"
             ? element.width / 2
@@ -1331,7 +1337,7 @@ export const renderElementToSvg = (
           const text = svgRoot.ownerDocument!.createElementNS(SVG_NS, "text");
           text.textContent = lines[i];
           text.setAttribute("x", `${horizontalOffset}`);
-          text.setAttribute("y", `${i * lineHeight}`);
+          text.setAttribute("y", `${i * lineHeightPx}`);
           text.setAttribute("font-family", getFontFamilyString(element));
           text.setAttribute("font-size", `${element.fontSize}px`);
           text.setAttribute("fill", element.strokeColor);

src/tests/__snapshots__/linearElementEditor.test.tsx.snap

@@ -5,7 +5,7 @@ exports[`Test Linear Elements Test bound text element should match styles for te
   class="excalidraw-wysiwyg"
   data-type="wysiwyg"
   dir="auto"
-  style="position: absolute; display: inline-block; min-height: 1em; margin: 0px; padding: 0px; border: 0px; outline: 0; resize: none; background: transparent; overflow: hidden; z-index: var(--zIndex-wysiwyg); word-break: break-word; white-space: pre-wrap; overflow-wrap: break-word; box-sizing: content-box; width: 10.5px; height: 24px; left: 35px; top: 8px; transform: translate(0px, 0px) scale(1) rotate(0deg); text-align: center; vertical-align: middle; color: rgb(0, 0, 0); opacity: 1; filter: var(--theme-filter); max-height: -8px; font: Emoji 20px 20px; line-height: 24px; font-family: Virgil, Segoe UI Emoji;"
+  style="position: absolute; display: inline-block; min-height: 1em; margin: 0px; padding: 0px; border: 0px; outline: 0; resize: none; background: transparent; overflow: hidden; z-index: var(--zIndex-wysiwyg); word-break: break-word; white-space: pre-wrap; overflow-wrap: break-word; box-sizing: content-box; width: 10.5px; height: 25px; left: 35px; top: 7.5px; transform: translate(0px, 0px) scale(1) rotate(0deg); text-align: center; vertical-align: middle; color: rgb(0, 0, 0); opacity: 1; filter: var(--theme-filter); max-height: -7.5px; font: Emoji 20px 20px; line-height: 1.25; font-family: Virgil, Segoe UI Emoji;"
   tabindex="0"
   wrap="off"
 />

src/tests/clipboard.test.tsx

@@ -3,8 +3,10 @@ import { render, waitFor, GlobalTestState } from "./test-utils";
 import { Pointer, Keyboard } from "./helpers/ui";
 import ExcalidrawApp from "../excalidraw-app";
 import { KEYS } from "../keys";
-import { getApproxLineHeight } from "../element/textElement";
-import { getFontString } from "../utils";
+import {
+  getDefaultLineHeight,
+  getLineHeightInPx,
+} from "../element/textElement";
 import { getElementBounds } from "../element";
 import { NormalizedZoomValue } from "../types";
 
@@ -118,12 +120,10 @@ describe("paste text as single lines", () => {
 
   it("should space items correctly", async () => {
     const text = "hkhkjhki\njgkjhffjh\njgkjhffjh";
-    const lineHeight =
-      getApproxLineHeight(
-        getFontString({
-          fontSize: h.app.state.currentItemFontSize,
-          fontFamily: h.app.state.currentItemFontFamily,
-        }),
+    const lineHeightPx =
+      getLineHeightInPx(
+        h.app.state.currentItemFontSize,
+        getDefaultLineHeight(h.state.currentItemFontFamily),
       ) +
       10 / h.app.state.zoom.value;
     mouse.moveTo(100, 100);
@@ -135,19 +135,17 @@ describe("paste text as single lines", () => {
       for (let i = 1; i < h.elements.length; i++) {
         // eslint-disable-next-line @typescript-eslint/no-unused-vars
         const [fx, elY] = getElementBounds(h.elements[i]);
-        expect(elY).toEqual(firstElY + lineHeight * i);
+        expect(elY).toEqual(firstElY + lineHeightPx * i);
       }
     });
   });
 
   it("should leave a space for blank new lines", async () => {
     const text = "hkhkjhki\n\njgkjhffjh";
-    const lineHeight =
-      getApproxLineHeight(
-        getFontString({
-          fontSize: h.app.state.currentItemFontSize,
-          fontFamily: h.app.state.currentItemFontFamily,
-        }),
+    const lineHeightPx =
+      getLineHeightInPx(
+        h.app.state.currentItemFontSize,
+        getDefaultLineHeight(h.state.currentItemFontFamily),
       ) +
       10 / h.app.state.zoom.value;
     mouse.moveTo(100, 100);
@@ -158,7 +156,7 @@ describe("paste text as single lines", () => {
       const [fx, firstElY] = getElementBounds(h.elements[0]);
       // eslint-disable-next-line @typescript-eslint/no-unused-vars
       const [lx, lastElY] = getElementBounds(h.elements[1]);
-      expect(lastElY).toEqual(firstElY + lineHeight * 2);
+      expect(lastElY).toEqual(firstElY + lineHeightPx * 2);
     });
   });
 });
@@ -224,7 +222,7 @@ describe("Paste bound text container", () => {
       await sleep(1);
       expect(h.elements.length).toEqual(2);
       const container = h.elements[0];
-      expect(container.height).toBe(354);
+      expect(container.height).toBe(368);
       expect(container.width).toBe(166);
     });
   });
@@ -247,7 +245,7 @@ describe("Paste bound text container", () => {
       await sleep(1);
       expect(h.elements.length).toEqual(2);
       const container = h.elements[0];
-      expect(container.height).toBe(740);
+      expect(container.height).toBe(770);
       expect(container.width).toBe(166);
     });
   });

src/tests/data/__snapshots__/restore.test.ts.snap

@@ -291,6 +291,7 @@ Object {
   "height": 100,
   "id": "id-text01",
   "isDeleted": false,
+  "lineHeight": 1.25,
   "link": null,
   "locked": false,
   "opacity": 100,
@@ -312,7 +313,7 @@ Object {
   "verticalAlign": "middle",
   "width": 100,
   "x": -20,
-  "y": -8.4,
+  "y": -8.75,
 }
 `;
 
@@ -329,6 +330,7 @@ Object {
   "height": 100,
   "id": "id-text01",
   "isDeleted": false,
+  "lineHeight": 1.25,
   "link": null,
   "locked": false,
   "opacity": 100,

src/tests/helpers/api.ts

@@ -181,11 +181,13 @@ export class API {
         });
         break;
       case "text":
+        const fontSize = rest.fontSize ?? appState.currentItemFontSize;
+        const fontFamily = rest.fontFamily ?? appState.currentItemFontFamily;
         element = newTextElement({
           ...base,
           text: rest.text || "test",
-          fontSize: rest.fontSize ?? appState.currentItemFontSize,
-          fontFamily: rest.fontFamily ?? appState.currentItemFontFamily,
+          fontSize,
+          fontFamily,
           textAlign: rest.textAlign ?? appState.currentItemTextAlign,
           verticalAlign: rest.verticalAlign ?? DEFAULT_VERTICAL_ALIGN,
           containerId: rest.containerId ?? undefined,

src/tests/linearElementEditor.test.tsx

@@ -1031,7 +1031,7 @@ describe("Test Linear Elements", () => {
       expect({ width: container.width, height: container.height })
         .toMatchInlineSnapshot(`
         Object {
-          "height": 128,
+          "height": 130,
           "width": 367,
         }
       `);
@@ -1040,7 +1040,7 @@ describe("Test Linear Elements", () => {
         .toMatchInlineSnapshot(`
         Object {
           "x": 272,
-          "y": 46,
+          "y": 45,
         }
       `);
       expect((h.elements[1] as ExcalidrawTextElementWithContainer).text)
@@ -1052,11 +1052,11 @@ describe("Test Linear Elements", () => {
         .toMatchInlineSnapshot(`
         Array [
           20,
-          36,
+          35,
           502,
-          94,
+          95,
           205.9061448421403,
-          53,
+          52.5,
         ]
       `);
     });
@@ -1090,7 +1090,7 @@ describe("Test Linear Elements", () => {
       expect({ width: container.width, height: container.height })
         .toMatchInlineSnapshot(`
         Object {
-          "height": 128,
+          "height": 130,
           "width": 340,
         }
       `);
@@ -1099,7 +1099,7 @@ describe("Test Linear Elements", () => {
         .toMatchInlineSnapshot(`
         Object {
           "x": 75,
-          "y": -4,
+          "y": -5,
         }
       `);
       expect(textElement.text).toMatchInlineSnapshot(`