1 files changed, 164 insertions, 0 deletions
diff --git a/packages/excalidraw/visualdebug.ts b/packages/excalidraw/visualdebug.ts
new file mode 100644
index 0000000..862f2cf
--- /dev/null
+++ b/packages/excalidraw/visualdebug.ts
@@ -0,0 +1,164 @@
+import type { Curve } from "@excalidraw/math";
+import {
+  isLineSegment,
+  lineSegment,
+  pointFrom,
+  type GlobalPoint,
+  type LocalPoint,
+} from "@excalidraw/math";
+import type { LineSegment } from "@excalidraw/utils";
+import type { Bounds } from "./element/bounds";
+import { isBounds } from "./element/typeChecks";
+
+// The global data holder to collect the debug operations
+declare global {
+  interface Window {
+    visualDebug?: {
+      data: DebugElement[][];
+      currentFrame?: number;
+    };
+  }
+}
+
+export type DebugElement = {
+  color: string;
+  data: LineSegment<GlobalPoint> | Curve<GlobalPoint>;
+  permanent: boolean;
+};
+
+export const debugDrawCubicBezier = (
+  c: Curve<GlobalPoint>,
+  opts?: {
+    color?: string;
+    permanent?: boolean;
+  },
+) => {
+  addToCurrentFrame({
+    color: opts?.color ?? "purple",
+    permanent: !!opts?.permanent,
+    data: c,
+  });
+};
+
+export const debugDrawLine = (
+  segment: LineSegment<GlobalPoint> | LineSegment<GlobalPoint>[],
+  opts?: {
+    color?: string;
+    permanent?: boolean;
+  },
+) => {
+  const segments = (
+    isLineSegment(segment) ? [segment] : segment
+  ) as LineSegment<GlobalPoint>[];
+
+  segments.forEach((data) =>
+    addToCurrentFrame({
+      color: opts?.color ?? "red",
+      data,
+      permanent: !!opts?.permanent,
+    }),
+  );
+};
+
+export const debugDrawPoint = (
+  p: GlobalPoint,
+  opts?: {
+    color?: string;
+    permanent?: boolean;
+    fuzzy?: boolean;
+  },
+) => {
+  const xOffset = opts?.fuzzy ? Math.random() * 3 : 0;
+  const yOffset = opts?.fuzzy ? Math.random() * 3 : 0;
+
+  debugDrawLine(
+    lineSegment(
+      pointFrom<GlobalPoint>(p[0] + xOffset - 10, p[1] + yOffset - 10),
+      pointFrom<GlobalPoint>(p[0] + xOffset + 10, p[1] + yOffset + 10),
+    ),
+    {
+      color: opts?.color ?? "cyan",
+      permanent: opts?.permanent,
+    },
+  );
+  debugDrawLine(
+    lineSegment(
+      pointFrom<GlobalPoint>(p[0] + xOffset - 10, p[1] + yOffset + 10),
+      pointFrom<GlobalPoint>(p[0] + xOffset + 10, p[1] + yOffset - 10),
+    ),
+    {
+      color: opts?.color ?? "cyan",
+      permanent: opts?.permanent,
+    },
+  );
+};
+
+export const debugDrawBounds = (
+  box: Bounds | Bounds[],
+  opts?: {
+    color?: string;
+    permanent?: boolean;
+  },
+) => {
+  (isBounds(box) ? [box] : box).forEach((bbox) =>
+    debugDrawLine(
+      [
+        lineSegment(
+          pointFrom<GlobalPoint>(bbox[0], bbox[1]),
+          pointFrom<GlobalPoint>(bbox[2], bbox[1]),
+        ),
+        lineSegment(
+          pointFrom<GlobalPoint>(bbox[2], bbox[1]),
+          pointFrom<GlobalPoint>(bbox[2], bbox[3]),
+        ),
+        lineSegment(
+          pointFrom<GlobalPoint>(bbox[2], bbox[3]),
+          pointFrom<GlobalPoint>(bbox[0], bbox[3]),
+        ),
+        lineSegment(
+          pointFrom<GlobalPoint>(bbox[0], bbox[3]),
+          pointFrom<GlobalPoint>(bbox[0], bbox[1]),
+        ),
+      ],
+      {
+        color: opts?.color ?? "green",
+        permanent: !!opts?.permanent,
+      },
+    ),
+  );
+};
+
+export const debugDrawPoints = (
+  {
+    x,
+    y,
+    points,
+  }: {
+    x: number;
+    y: number;
+    points: LocalPoint[];
+  },
+  options?: any,
+) => {
+  points.forEach((p) =>
+    debugDrawPoint(pointFrom<GlobalPoint>(x + p[0], y + p[1]), options),
+  );
+};
+
+export const debugCloseFrame = () => {
+  window.visualDebug?.data.push([]);
+};
+
+export const debugClear = () => {
+  if (window.visualDebug?.data) {
+    window.visualDebug.data = [];
+  }
+};
+
+const addToCurrentFrame = (element: DebugElement) => {
+  if (window.visualDebug?.data && window.visualDebug.data.length === 0) {
+    window.visualDebug.data[0] = [];
+  }
+  window.visualDebug?.data &&
+    window.visualDebug.data[window.visualDebug.data.length - 1].push(element);
+};