feat: edit moving source trajectories

2026-08-28 16:04:55 +09:00
parent acb36bf15d
commit a20b55e8e2
8 changed files with 499 additions and 15 deletions
@@ -7,11 +7,123 @@ export const DEFAULT_VIEW_PLANE = Object.freeze({

 export const SOURCE_COLORS = ["#65f2bf", "#58c7e8", "#ffc56e", "#ff8f87", "#be9bff", "#8ee36b"];

+export const MAX_TRAJECTORY_KEYFRAMES = 4096;
+
+function copyPosition(position) {
+  return position.map((coordinate) => Number(coordinate));
+}
+
+function clamp(value, minimum, maximum) {
+  return Math.max(minimum, Math.min(maximum, value));
+}
+
+export function synchronizeSourcePosition(source) {
+  if (Array.isArray(source.trajectory) && source.trajectory.length > 0) {
+    source.position = copyPosition(source.trajectory[0].position);
+  }
+  return source.position;
+}
+
+export function createDefaultTrajectory(source, sceneDuration, plane = DEFAULT_VIEW_PLANE) {
+  const start = copyPosition(source.position);
+  const width = Number.isFinite(plane?.xMax - plane?.xMin) && plane.xMax > plane.xMin
+    ? plane.xMax - plane.xMin
+    : DEFAULT_VIEW_PLANE.xMax - DEFAULT_VIEW_PLANE.xMin;
+  const minimum = Number.isFinite(plane?.xMin) ? plane.xMin : DEFAULT_VIEW_PLANE.xMin;
+  const maximum = Number.isFinite(plane?.xMax) ? plane.xMax : DEFAULT_VIEW_PLANE.xMax;
+  const offset = Math.max(0.1, width * 0.25);
+  const rightRoom = maximum - start[0];
+  const leftRoom = start[0] - minimum;
+  const direction = rightRoom >= offset || rightRoom >= leftRoom ? 1 : -1;
+  const endX = clamp(start[0] + direction * offset, minimum, maximum);
+  return [
+    { time: 0, position: start },
+    { time: sceneDuration, position: [endX, start[1], start[2]] },
+  ];
+}
+
+export function enableSourceTrajectory(source, sceneDuration, plane = DEFAULT_VIEW_PLANE) {
+  if (!Array.isArray(source.trajectory) || source.trajectory.length < 2) {
+    source.trajectory = createDefaultTrajectory(source, sceneDuration, plane);
+  }
+  synchronizeSourcePosition(source);
+  return source.trajectory;
+}
+
+export function disableSourceTrajectory(source) {
+  synchronizeSourcePosition(source);
+  delete source.trajectory;
+}
+
+export function insertTrajectoryKeyframe(source) {
+  if (!Array.isArray(source.trajectory) || source.trajectory.length < 2 ||
+      source.trajectory.length >= MAX_TRAJECTORY_KEYFRAMES) {
+    return -1;
+  }
+  let leftIndex = 0;
+  let largestGap = -Infinity;
+  for (let index = 0; index < source.trajectory.length - 1; index += 1) {
+    const gap = source.trajectory[index + 1].time - source.trajectory[index].time;
+    if (gap > largestGap) {
+      largestGap = gap;
+      leftIndex = index;
+    }
+  }
+  if (!(largestGap > 0)) return -1;
+  const left = source.trajectory[leftIndex];
+  const right = source.trajectory[leftIndex + 1];
+  source.trajectory.splice(leftIndex + 1, 0, {
+    time: left.time + largestGap / 2,
+    position: left.position.map((coordinate, index) =>
+      coordinate + (right.position[index] - coordinate) / 2,
+    ),
+  });
+  synchronizeSourcePosition(source);
+  return leftIndex + 1;
+}
+
+export function removeTrajectoryKeyframe(source, index) {
+  if (!Array.isArray(source.trajectory) || source.trajectory.length <= 2 ||
+      !Number.isInteger(index) || index < 0 || index >= source.trajectory.length) return false;
+  source.trajectory.splice(index, 1);
+  synchronizeSourcePosition(source);
+  return true;
+}
+
+export function trajectoryTimeBounds(source, index, sceneDuration) {
+  const trajectory = source.trajectory;
+  const duration = Number.isFinite(sceneDuration) && sceneDuration > 0 ? sceneDuration : 0;
+  const gap = Math.max(1e-9, duration * 1e-9);
+  return {
+    minimum: index === 0 ? 0 : trajectory[index - 1].time + gap,
+    maximum: index === trajectory.length - 1 ? duration : trajectory[index + 1].time - gap,
+  };
+}
+
+export function updateTrajectoryKeyframeTime(source, index, requestedTime, sceneDuration) {
+  if (!Number.isFinite(requestedTime) || !source.trajectory?.[index]) return source.trajectory?.[index]?.time;
+  const { minimum, maximum } = trajectoryTimeBounds(source, index, sceneDuration);
+  source.trajectory[index].time = clamp(requestedTime, minimum, maximum);
+  return source.trajectory[index].time;
+}
+
+export function scaleSceneTrajectories(scene, previousDuration, nextDuration) {
+  if (!Number.isFinite(previousDuration) || previousDuration <= 0 ||
+      !Number.isFinite(nextDuration) || nextDuration <= 0) return;
+  const scale = nextDuration / previousDuration;
+  for (const source of scene.sources) {
+    if (!Array.isArray(source.trajectory)) continue;
+    source.trajectory.forEach((keyframe) => { keyframe.time *= scale; });
+    synchronizeSourcePosition(source);
+  }
+}
+
 export function prepareSceneForEditing(scene) {
  const prepared = structuredClone(scene);
  prepared.assets ??= [];
  prepared.ambient ??= [];
  prepared.mix ??= { normalization: "none", targetPeak: 0.95 };
+  prepared.sources.forEach(synchronizeSourcePosition);
  return prepared;
 }