Initial v2 overhaul

packages/streamwall-shared/src/geometry.ts

@@ -0,0 +1,109 @@
+import { Rectangle } from 'electron'
+import { isEqual } from 'lodash-es'
+import { ContentKind } from './types'
+
+export interface ViewPos extends Rectangle {
+  /**
+   * Grid space indexes inhabited by the view.
+   */
+  spaces: number[]
+}
+
+export interface ViewContent {
+  url: string
+  kind: ContentKind
+}
+export type ViewContentMap = Map<string, ViewContent>
+
+export function boxesFromViewContentMap(
+  width: number,
+  height: number,
+  viewContentMap: ViewContentMap,
+) {
+  const boxes = []
+  const visited = new Set()
+
+  function isPosContent(
+    x: number,
+    y: number,
+    content: ViewContent | undefined,
+  ) {
+    const checkIdx = width * y + x
+    return (
+      !visited.has(checkIdx) &&
+      isEqual(viewContentMap.get(String(checkIdx)), content)
+    )
+  }
+
+  function findLargestBox(x: number, y: number) {
+    const idx = width * y + x
+    const spaces = [idx]
+    const content = viewContentMap.get(String(idx))
+
+    let maxY
+    for (maxY = y + 1; maxY < height; maxY++) {
+      if (!isPosContent(x, maxY, content)) {
+        break
+      }
+      spaces.push(width * maxY + x)
+    }
+
+    let cx = x
+    let cy = y
+    scan: for (cx = x + 1; cx < width; cx++) {
+      for (cy = y; cy < maxY; cy++) {
+        if (!isPosContent(cx, cy, content)) {
+          break scan
+        }
+      }
+      for (let cy = y; cy < maxY; cy++) {
+        spaces.push(width * cy + cx)
+      }
+    }
+    const w = cx - x
+    const h = maxY - y
+    spaces.sort()
+    return { content, x, y, w, h, spaces }
+  }
+
+  for (let y = 0; y < width; y++) {
+    for (let x = 0; x < height; x++) {
+      const idx = width * y + x
+      if (visited.has(idx) || viewContentMap.get(String(idx)) === undefined) {
+        continue
+      }
+
+      const box = findLargestBox(x, y)
+      boxes.push(box)
+      for (const boxIdx of box.spaces) {
+        visited.add(boxIdx)
+      }
+    }
+  }
+
+  return boxes
+}
+
+export function idxToCoords(gridCount: number, idx: number) {
+  const x = idx % gridCount
+  const y = Math.floor(idx / gridCount)
+  return { x, y }
+}
+
+export function idxInBox(
+  gridCount: number,
+  start: number,
+  end: number,
+  idx: number,
+) {
+  const { x: startX, y: startY } = idxToCoords(gridCount, start)
+  const { x: endX, y: endY } = idxToCoords(gridCount, end)
+  const { x, y } = idxToCoords(gridCount, idx)
+  const lowX = Math.min(startX, endX)
+  const highX = Math.max(startX, endX)
+  const lowY = Math.min(startY, endY)
+  const highY = Math.max(startY, endY)
+  const xInBox = x >= lowX && x <= highX
+  const yInBox = y >= lowY && y <= highY
+  return xInBox && yInBox
+}