refactor: packages/

1 files changed, 75 insertions, 0 deletions

diff --git a/packages/excalidraw/renderer/helpers.ts b/packages/excalidraw/renderer/helpers.ts
new file mode 100644
index 0000000..90f4009
--- /dev/null
+++ b/packages/excalidraw/renderer/helpers.ts
@@ -0,0 +1,75 @@
+import type { StaticCanvasAppState, AppState } from "../types";
+
+import type { StaticCanvasRenderConfig } from "../scene/types";
+
+import { THEME, THEME_FILTER } from "../constants";
+
+export const fillCircle = (
+  context: CanvasRenderingContext2D,
+  cx: number,
+  cy: number,
+  radius: number,
+  stroke = true,
+) => {
+  context.beginPath();
+  context.arc(cx, cy, radius, 0, Math.PI * 2);
+  context.fill();
+  if (stroke) {
+    context.stroke();
+  }
+};
+
+export const getNormalizedCanvasDimensions = (
+  canvas: HTMLCanvasElement,
+  scale: number,
+): [number, number] => {
+  // When doing calculations based on canvas width we should used normalized one
+  return [canvas.width / scale, canvas.height / scale];
+};
+
+export const bootstrapCanvas = ({
+  canvas,
+  scale,
+  normalizedWidth,
+  normalizedHeight,
+  theme,
+  isExporting,
+  viewBackgroundColor,
+}: {
+  canvas: HTMLCanvasElement;
+  scale: number;
+  normalizedWidth: number;
+  normalizedHeight: number;
+  theme?: AppState["theme"];
+  isExporting?: StaticCanvasRenderConfig["isExporting"];
+  viewBackgroundColor?: StaticCanvasAppState["viewBackgroundColor"];
+}): CanvasRenderingContext2D => {
+  const context = canvas.getContext("2d")!;
+
+  context.setTransform(1, 0, 0, 1, 0, 0);
+  context.scale(scale, scale);
+
+  if (isExporting && theme === THEME.DARK) {
+    context.filter = THEME_FILTER;
+  }
+
+  // Paint background
+  if (typeof viewBackgroundColor === "string") {
+    const hasTransparence =
+      viewBackgroundColor === "transparent" ||
+      viewBackgroundColor.length === 5 || // #RGBA
+      viewBackgroundColor.length === 9 || // #RRGGBBA
+      /(hsla|rgba)\(/.test(viewBackgroundColor);
+    if (hasTransparence) {
+      context.clearRect(0, 0, normalizedWidth, normalizedHeight);
+    }
+    context.save();
+    context.fillStyle = viewBackgroundColor;
+    context.fillRect(0, 0, normalizedWidth, normalizedHeight);
+    context.restore();
+  } else {
+    context.clearRect(0, 0, normalizedWidth, normalizedHeight);
+  }
+
+  return context;
+};