1 files changed, 105 insertions, 0 deletions
diff --git a/packages/excalidraw/cursor.ts b/packages/excalidraw/cursor.ts
new file mode 100644
index 0000000..759b7a4
--- /dev/null
+++ b/packages/excalidraw/cursor.ts
@@ -0,0 +1,105 @@
+import { CURSOR_TYPE, MIME_TYPES, THEME } from "./constants";
+import OpenColor from "open-color";
+import type { AppState, DataURL } from "./types";
+import { isHandToolActive, isEraserActive } from "./appState";
+
+const laserPointerCursorSVG_tag = `<svg viewBox="0 0 24 24" stroke-width="1" width="28" height="28" xmlns="http://www.w3.org/2000/svg">`;
+const laserPointerCursorBackgroundSVG = `<path d="M6.164 11.755a5.314 5.314 0 0 1-4.932-5.298 5.314 5.314 0 0 1 5.311-5.311 5.314 5.314 0 0 1 5.307 5.113l8.773 8.773a3.322 3.322 0 0 1 0 4.696l-.895.895a3.322 3.322 0 0 1-4.696 0l-8.868-8.868Z" style="fill:#fff"/>`;
+const laserPointerCursorIconSVG = `<path stroke="#1b1b1f" fill="#fff" d="m7.868 11.113 7.773 7.774a2.359 2.359 0 0 0 1.667.691 2.368 2.368 0 0 0 2.357-2.358c0-.625-.248-1.225-.69-1.667L11.201 7.78 9.558 9.469l-1.69 1.643v.001Zm10.273 3.606-3.333 3.333m-3.25-6.583 2 2m-7-7 3 3M3.664 3.625l1 1M2.529 6.922l1.407-.144m5.735-2.932-1.118.866M4.285 9.823l.758-1.194m1.863-6.207-.13 1.408"/>`;
+
+const laserPointerCursorDataURL_lightMode = `data:${
+  MIME_TYPES.svg
+},${encodeURIComponent(
+  `${laserPointerCursorSVG_tag}${laserPointerCursorIconSVG}</svg>`,
+)}`;
+const laserPointerCursorDataURL_darkMode = `data:${
+  MIME_TYPES.svg
+},${encodeURIComponent(
+  `${laserPointerCursorSVG_tag}${laserPointerCursorBackgroundSVG}${laserPointerCursorIconSVG}</svg>`,
+)}`;
+
+export const resetCursor = (interactiveCanvas: HTMLCanvasElement | null) => {
+  if (interactiveCanvas) {
+    interactiveCanvas.style.cursor = "";
+  }
+};
+
+export const setCursor = (
+  interactiveCanvas: HTMLCanvasElement | null,
+  cursor: string,
+) => {
+  if (interactiveCanvas) {
+    interactiveCanvas.style.cursor = cursor;
+  }
+};
+
+let eraserCanvasCache: any;
+let previewDataURL: string;
+export const setEraserCursor = (
+  interactiveCanvas: HTMLCanvasElement | null,
+  theme: AppState["theme"],
+) => {
+  const cursorImageSizePx = 20;
+
+  const drawCanvas = () => {
+    const isDarkTheme = theme === THEME.DARK;
+    eraserCanvasCache = document.createElement("canvas");
+    eraserCanvasCache.theme = theme;
+    eraserCanvasCache.height = cursorImageSizePx;
+    eraserCanvasCache.width = cursorImageSizePx;
+    const context = eraserCanvasCache.getContext("2d")!;
+    context.lineWidth = 1;
+    context.beginPath();
+    context.arc(
+      eraserCanvasCache.width / 2,
+      eraserCanvasCache.height / 2,
+      5,
+      0,
+      2 * Math.PI,
+    );
+    context.fillStyle = isDarkTheme ? OpenColor.black : OpenColor.white;
+    context.fill();
+    context.strokeStyle = isDarkTheme ? OpenColor.white : OpenColor.black;
+    context.stroke();
+    previewDataURL = eraserCanvasCache.toDataURL(MIME_TYPES.svg) as DataURL;
+  };
+  if (!eraserCanvasCache || eraserCanvasCache.theme !== theme) {
+    drawCanvas();
+  }
+
+  setCursor(
+    interactiveCanvas,
+    `url(${previewDataURL}) ${cursorImageSizePx / 2} ${
+      cursorImageSizePx / 2
+    }, auto`,
+  );
+};
+
+export const setCursorForShape = (
+  interactiveCanvas: HTMLCanvasElement | null,
+  appState: Pick<AppState, "activeTool" | "theme">,
+) => {
+  if (!interactiveCanvas) {
+    return;
+  }
+  if (appState.activeTool.type === "selection") {
+    resetCursor(interactiveCanvas);
+  } else if (isHandToolActive(appState)) {
+    interactiveCanvas.style.cursor = CURSOR_TYPE.GRAB;
+  } else if (isEraserActive(appState)) {
+    setEraserCursor(interactiveCanvas, appState.theme);
+    // do nothing if image tool is selected which suggests there's
+    // a image-preview set as the cursor
+    // Ignore custom type as well and let host decide
+  } else if (appState.activeTool.type === "laser") {
+    const url =
+      appState.theme === THEME.LIGHT
+        ? laserPointerCursorDataURL_lightMode
+        : laserPointerCursorDataURL_darkMode;
+    interactiveCanvas.style.cursor = `url(${url}), auto`;
+  } else if (!["image", "custom"].includes(appState.activeTool.type)) {
+    interactiveCanvas.style.cursor = CURSOR_TYPE.CROSSHAIR;
+  } else if (appState.activeTool.type !== "image") {
+    interactiveCanvas.style.cursor = CURSOR_TYPE.AUTO;
+  }
+};