| 1 | import { Matrix4, Quaternion, Vector3 } from "three"; |
| 2 | import { nearestDeviceView } from "./deviceViewSnap.ts"; |
| 3 | import type { DeviceScreenSize } from "./stream.ts"; |
| 4 | |
| 5 | export type DuoRestFace = "cover" | "inside" | "left" | "right"; |
| 6 | export type DuoRestFrame = { face: DuoRestFace; normal: Vector3; up: Vector3; center: Vector3 }; |
| 7 | export type DuoViewSnap = { |
| 8 | rotation: Quaternion; |
| 9 | face: DuoRestFace; |
| 10 | orientation: DeviceScreenSize["orientation"]; |
| 11 | center: Vector3; |
| 12 | yawLimit: number; |
| 13 | }; |
| 14 | const orientations = [ |
| 15 | "portrait", |
| 16 | "landscape_left", |
| 17 | "portrait_upside_down", |
| 18 | "landscape_right", |
| 19 | ] as const; |
| 20 | const z = new Vector3(0, 0, 1); |
| 21 | const y = new Vector3(0, 1, 0); |
| 22 | |
| 23 | /** Build views from the actual hinged display planes, rather than model-specific Euler offsets. */ |
| 24 | export function duoViewSnaps(frames: readonly DuoRestFrame[], panel: 1 | 3) { |
| 25 | const snaps: DuoViewSnap[] = []; |
| 26 | for (const frame of frames) { |
| 27 | const normal = frame.normal.clone().normalize(); |
| 28 | if (normal.lengthSq() < 0.5) continue; |
| 29 | const right = frame.up.clone().cross(normal).normalize(); |
| 30 | const up = normal.clone().cross(right).normalize(); |
| 31 | const faceRotation = new Quaternion() |
| 32 | .setFromRotationMatrix(new Matrix4().makeBasis(right, up, normal)) |
| 33 | .invert(); |
| 34 | for (let index = 0; index < orientations.length; index++) { |
| 35 | // Only these rolls put the partner below the focused lid. Other quarter |
| 36 | // turns belong to the upright, whole-display family. |
| 37 | if (frame.face === "right" && index !== 0) continue; |
| 38 | if (frame.face === "left" && index !== 2) continue; |
| 39 | const roll = (panel === 3 ? Math.PI / 2 : 0) - (index * Math.PI) / 2; |
| 40 | const rotation = faceRotation.clone().premultiply(new Quaternion().setFromAxisAngle(z, roll)); |
| 41 | // A leaf-focused view looks slightly down onto its partner, as in a seated laptop. |
| 42 | if (frame.face === "left" || frame.face === "right") |
| 43 | rotation.premultiply(new Quaternion().setFromAxisAngle(new Vector3(1, 0, 0), Math.PI / 12)); |
| 44 | if ( |
| 45 | panel === 3 && |
| 46 | frames.some( |
| 47 | (leaf) => |
| 48 | (leaf.face === "left" || leaf.face === "right") && |
| 49 | leaf.normal.clone().applyQuaternion(rotation).z < 0.04, |
| 50 | ) |
| 51 | ) |
| 52 | continue; |
| 53 | // Bound yaw using both real leaf normals. A narrow fold cannot tolerate |
| 54 | // the same side view as a fully open display. |
| 55 | let yawLimit = frame.face === "cover" ? Math.PI / 9 : Math.PI / 3; |
| 56 | if (panel === 3) { |
| 57 | for (const sign of [-1, 1]) { |
| 58 | for (let step = 1; step <= 60; step++) { |
| 59 | const turn = new Quaternion().setFromAxisAngle(y, (sign * step * Math.PI) / 180); |
| 60 | if ( |
| 61 | frames.some( |
| 62 | (leaf) => |
| 63 | (leaf.face === "left" || leaf.face === "right") && |
| 64 | leaf.normal.clone().applyQuaternion(rotation).applyQuaternion(turn).z < 0.04, |
| 65 | ) |
| 66 | ) { |
| 67 | yawLimit = Math.min(yawLimit, ((step - 1) * Math.PI) / 180); |
| 68 | break; |
| 69 | } |
| 70 | } |
| 71 | } |
| 72 | } |
| 73 | snaps.push({ |
| 74 | rotation, |
| 75 | face: frame.face, |
| 76 | orientation: orientations[index]!, |
| 77 | center: frame.center.clone(), |
| 78 | yawLimit, |
| 79 | }); |
| 80 | } |
| 81 | } |
| 82 | return snaps; |
| 83 | } |
| 84 | |
| 85 | /** Fold-specific candidates use the base viewer's nearest-family selection. */ |
| 86 | export const nearestDuoView = nearestDeviceView<DuoViewSnap>; |