Refactor grid state tracking

This commit is contained in:
Robin Townsend 2023-02-07 23:27:49 -05:00
parent 978b0f08e8
commit 8d46687a54
2 changed files with 112 additions and 64 deletions

View file

@ -17,8 +17,11 @@ limitations under the License.
import { SpringRef, TransitionFn, useTransition } from "@react-spring/web";
import { EventTypes, Handler, useScroll } from "@use-gesture/react";
import React, {
Dispatch,
FC,
ReactNode,
SetStateAction,
useCallback,
useEffect,
useMemo,
useRef,
@ -39,8 +42,82 @@ import {
fillGaps,
forEachCellInArea,
cycleTileSize,
appendItems,
} from "./model";
interface GridState extends Grid {
/**
* The ID of the current state of the grid.
*/
generation: number;
}
const useGridState = (
columns: number | null,
items: TileDescriptor[]
): [GridState | null, Dispatch<SetStateAction<Grid>>] => {
const [grid, setGrid_] = useReactiveState<GridState | null>(
(prevGrid = null) => {
if (prevGrid === null) {
// We can't do anything if the column count isn't known yet
if (columns === null) {
return null;
} else {
prevGrid = { generation: 0, columns, cells: [] };
}
}
// Step 1: Update tiles that still exist, and remove tiles that have left
// the grid
const itemsById = new Map(items.map((i) => [i.id, i]));
const grid1: Grid = {
...prevGrid,
cells: prevGrid.cells.map((c) => {
if (c === undefined) return undefined;
const item = itemsById.get(c.item.id);
return item === undefined ? undefined : { ...c, item };
}),
};
// Step 2: Backfill gaps left behind by removed tiles
const grid2 = fillGaps(grid1);
// Step 3: Add new tiles to the end of the grid
const existingItemIds = new Set(
grid2.cells.filter((c) => c !== undefined).map((c) => c!.item.id)
);
const newItems = items.filter((i) => !existingItemIds.has(i.id));
const grid3 = appendItems(newItems, grid2);
return { ...grid3, generation: prevGrid.generation + 1 };
},
[columns, items]
);
const setGrid: Dispatch<SetStateAction<Grid>> = useCallback(
(action) => {
if (typeof action === "function") {
setGrid_((prevGrid) =>
prevGrid === null
? null
: {
...(action as (prev: Grid) => Grid)(prevGrid),
generation: prevGrid.generation + 1,
}
);
} else {
setGrid_((prevGrid) => ({
...action,
generation: prevGrid?.generation ?? 1,
}));
}
},
[setGrid_]
);
return [grid, setGrid];
};
interface Rect {
x: number;
y: number;
@ -133,55 +210,7 @@ export const NewVideoGrid: FC<Props> = ({
[gridBounds]
);
const [grid, setGrid] = useReactiveState<Grid | null>(
(prevGrid = null) => {
if (prevGrid === null) {
// We can't do anything if the column count isn't known yet
if (columns === null) {
return null;
} else {
prevGrid = { generation: slotGridGeneration, columns, cells: [] };
}
}
// Step 1: Update tiles that still exist, and remove tiles that have left
// the grid
const itemsById = new Map(items.map((i) => [i.id, i]));
const grid1: Grid = {
...prevGrid,
generation: prevGrid.generation + 1,
cells: prevGrid.cells.map((c) => {
if (c === undefined) return undefined;
const item = itemsById.get(c.item.id);
return item === undefined ? undefined : { ...c, item };
}),
};
// Step 2: Backfill gaps left behind by removed tiles
const grid2 = fillGaps(grid1);
// Step 3: Add new tiles to the end of the grid
const existingItemIds = new Set(
grid2.cells.filter((c) => c !== undefined).map((c) => c!.item.id)
);
const newItems = items.filter((i) => !existingItemIds.has(i.id));
const grid3: Grid = {
...grid2,
cells: [
...grid2.cells,
...newItems.map((i) => ({
item: i,
slot: true,
columns: 1,
rows: 1,
})),
],
};
return grid3;
},
[items, columns]
);
const [grid, setGrid] = useGridState(columns, items);
const [tiles] = useReactiveState<Tile[]>(
(prevTiles) => {
@ -189,9 +218,9 @@ export const NewVideoGrid: FC<Props> = ({
// the update, because grid and slotRects will be out of sync
if (slotGridGeneration !== grid?.generation) return prevTiles ?? [];
const slotCells = grid.cells.filter((c) => c?.slot) as Cell[];
const tileCells = grid.cells.filter((c) => c?.origin) as Cell[];
const tileRects = new Map<TileDescriptor, Rect>(
zipWith(slotCells, slotRects, (cell, rect) => [cell.item, rect])
zipWith(tileCells, slotRects, (cell, rect) => [cell.item, rect])
);
return items.map((item) => ({ ...tileRects.get(item)!, item }));
},
@ -247,7 +276,7 @@ export const NewVideoGrid: FC<Props> = ({
let slotId = 0;
for (let i = 0; i < grid.cells.length; i++) {
const cell = grid.cells[i];
if (cell?.slot) {
if (cell?.origin) {
const slotEnd = i + cell.columns - 1 + grid.columns * (cell.rows - 1);
forEachCellInArea(
i,

View file

@ -17,29 +17,34 @@ limitations under the License.
import TinyQueue from "tinyqueue";
import { TileDescriptor } from "./TileDescriptor";
/**
* A 1×1 cell in a grid which belongs to a tile.
*/
export interface Cell {
/**
* The item held by the slot containing this cell.
* The item displayed on the tile.
*/
item: TileDescriptor;
/**
* Whether this cell is the first cell of the containing slot.
* Whether this cell is the origin (top left corner) of the tile.
*/
// TODO: Rename to 'start'?
slot: boolean;
origin: boolean;
/**
* The width, in columns, of the containing slot.
* The width, in columns, of the tile.
*/
columns: number;
/**
* The height, in rows, of the containing slot.
* The height, in rows, of the tile.
*/
rows: number;
}
export interface Grid {
generation: number;
columns: number;
/**
* The cells of the grid, in left-to-right top-to-bottom order.
* undefined = empty.
*/
cells: (Cell | undefined)[];
}
@ -55,9 +60,9 @@ export function dijkstra(g: Grid): number[] {
const visit = (curr: number, via: number) => {
const viaCell = g.cells[via];
const viaLargeSlot =
const viaLargeTile =
viaCell !== undefined && (viaCell.rows > 1 || viaCell.columns > 1);
const distanceVia = distances[via] + (viaLargeSlot ? 4 : 1);
const distanceVia = distances[via] + (viaLargeTile ? 4 : 1);
if (distanceVia < distances[curr]) {
distances[curr] = distanceVia;
@ -252,6 +257,21 @@ export function fillGaps(g: Grid): Grid {
return result;
}
export function appendItems(items: TileDescriptor[], g: Grid): Grid {
return {
...g,
cells: [
...g.cells,
...items.map((i) => ({
item: i,
origin: true,
columns: 1,
rows: 1,
})),
],
};
}
export function cycleTileSize(tileId: string, g: Grid): Grid {
const from = g.cells.findIndex((c) => c?.item.id === tileId);
if (from === -1) return g; // Tile removed, no change
@ -273,7 +293,6 @@ export function cycleTileSize(tileId: string, g: Grid): Grid {
const gappyGrid: Grid = {
...g,
generation: g.generation + 1,
cells: new Array(g.cells.length + newRows * g.columns),
};
@ -318,7 +337,7 @@ export function cycleTileSize(tileId: string, g: Grid): Grid {
const toRow = row(to, g);
g.cells.forEach((c, src) => {
if (c?.slot && c.item.id !== tileId) {
if (c?.origin && c.item.id !== tileId) {
const offset =
row(src, g) > toRow + candidateHeight - 1 ? g.columns * newRows : 0;
forEachCellInArea(src, areaEnd(src, c.columns, c.rows, g), g, (c, i) => {
@ -333,7 +352,7 @@ export function cycleTileSize(tileId: string, g: Grid): Grid {
if (c !== undefined) displacedTiles.push(c);
gappyGrid.cells[i] = {
item: g.cells[from]!.item,
slot: i === to,
origin: i === to,
columns: toWidth,
rows: toHeight,
};