fix: preserve annotations while resizing selection

frontend/src/utils/annotationGeometry.ts

@@ -0,0 +1,28 @@
+export interface AnnotationPoint {
+  x: number
+  y: number
+}
+
+interface PointCollection {
+  points: AnnotationPoint[]
+}
+
+// Annotations are stored relative to the selection origin. Resizing from the
+// top or left moves that origin, so offset the local points in the opposite
+// direction to keep them attached to the same screen pixels.
+export function preserveAnnotationScreenPositions(
+  annotations: PointCollection[],
+  previousOrigin: AnnotationPoint,
+  nextOrigin: AnnotationPoint
+) {
+  const dx = previousOrigin.x - nextOrigin.x
+  const dy = previousOrigin.y - nextOrigin.y
+  if (dx === 0 && dy === 0) return
+
+  for (const annotation of annotations) {
+    for (const point of annotation.points) {
+      point.x += dx
+      point.y += dy
+    }
+  }
+}

frontend/src/views/CaptureOverlay.vue

@@ -10,6 +10,7 @@ import saveIcon from '../assets/icons/save-local.svg?raw'
 import saveRemoteIcon from '../assets/icons/save-remote.svg?raw'
 import ftpIcon from '../assets/icons/ftp.svg?raw'
 import uploadIcon from '../assets/icons/upload.svg?raw'
+import { preserveAnnotationScreenPositions } from '../utils/annotationGeometry'
 
 interface Props {
   width: number
@@ -539,12 +540,16 @@ function resizeSelection(p: Point) {
   right = clamp(right, 0, props.width)
   top = clamp(top, 0, props.height)
   bottom = clamp(bottom, 0, props.height)
-  rect.value = {
+  const nextRect = {
     x: Math.min(left, right),
     y: Math.min(top, bottom),
     w: Math.abs(right - left),
     h: Math.abs(bottom - top),
   }
+  if (rect.value) {
+    preserveAnnotationScreenPositions(annotations.value, rect.value, nextRect)
+  }
+  rect.value = nextRect
 }
 
 function selectTool(tool: Tool) {