From f1043734438c8518a302f698d9ae6583a75f0c14 Mon Sep 17 00:00:00 2001
From: cashmere <cashmere@autistici.org>
Date: Sun, 16 Aug 2026 06:16:56 +0200
Subject: feat: add transitions, track mixing, and voiceover controls

---
 apps/web/src/services/renderer/resolve.ts | 67 +++++++++++++++++++++----------
 1 file changed, 46 insertions(+), 21 deletions(-)

(limited to 'apps/web/src/services/renderer/resolve.ts')

diff --git a/apps/web/src/services/renderer/resolve.ts b/apps/web/src/services/renderer/resolve.ts
index 12f57e30..54a6eca4 100644
--- a/apps/web/src/services/renderer/resolve.ts
+++ b/apps/web/src/services/renderer/resolve.ts
@@ -22,6 +22,7 @@ import {
 } from "@/text/measure-element";
 import { resolveColorAtTime, resolveOpacityAtTime } from "@/animation/values";
 import { resolveTransformAtTime } from "@/rendering/animation-values";
+import { applyVisualTransition } from "@/rendering/transition";
 import { videoCache } from "@/services/video-cache/service";
 import type { CanvasRenderer } from "./canvas-renderer";
 import type { AnyBaseNode } from "./nodes/base-node";
@@ -148,12 +149,13 @@ function resolveVisualState({
 		return null;
 	}
 
+	const contentDuration = params.contentDuration ?? params.duration;
 	const localTime = getElementLocalTime({
 		timelineTime: context.time,
 		elementStartTime: params.timeOffset,
-		elementDuration: params.duration,
+		elementDuration: contentDuration,
 	});
-	const transform = applyMotionEffects({
+	const baseTransform = applyMotionEffects({
 		baseTransform: resolveTransformAtTime({
 			baseTransform: params.transform,
 			animations: params.animations,
@@ -162,15 +164,24 @@ function resolveVisualState({
 		effects: params.effects,
 		animations: params.animations,
 		localTime,
-		duration: params.duration,
+		duration: contentDuration,
 		canvasWidth: context.renderer.width,
 		canvasHeight: context.renderer.height,
 	});
-	const opacity = resolveOpacityAtTime({
+	const baseOpacity = resolveOpacityAtTime({
 		baseOpacity: params.opacity,
 		animations: params.animations,
 		localTime,
 	});
+	const transitionState = applyVisualTransition({
+		baseTransform,
+		transition: params.transition,
+		localTime,
+		duration: contentDuration,
+		canvasWidth: context.renderer.width,
+	});
+	const transform = transitionState.transform;
+	const opacity = baseOpacity * transitionState.opacityMultiplier;
 	const containScale = Math.min(
 		context.renderer.width / sourceWidth,
 		context.renderer.height / sourceHeight,
@@ -207,17 +218,21 @@ async function resolveVideoNode({
 	if (clipTime < 0 || clipTime >= node.params.duration) {
 		return null;
 	}
+	const contentDuration = node.params.contentDuration ?? node.params.duration;
+	const sourceClipTime = Math.min(clipTime, Math.max(0, contentDuration - 1));
 
 	const sourceTimeTicks =
 		node.params.trimStart +
 		getSourceTimeAtClipTime({
-			clipTime,
+			clipTime: sourceClipTime,
 			retime: node.params.retime,
 		});
 	const frame = await videoCache.getFrameAt({
 		mediaId: node.params.mediaId,
 		file: node.params.file,
-		time: mediaTimeToSeconds({ time: roundMediaTime({ time: sourceTimeTicks }) }),
+		time: mediaTimeToSeconds({
+			time: roundMediaTime({ time: sourceTimeTicks }),
+		}),
 	});
 	if (!frame) {
 		return null;
@@ -344,18 +359,27 @@ function resolveTextNode({
 		elementDuration: node.params.duration,
 	});
 	const background = buildTextBackgroundFromElement({ element: node.params });
+	const baseTransform = resolveTransformAtTime({
+		baseTransform: node.params.transform,
+		animations: node.params.animations,
+		localTime,
+	});
+	const baseOpacity = resolveOpacityAtTime({
+		baseOpacity: node.params.opacity,
+		animations: node.params.animations,
+		localTime,
+	});
+	const transitionState = applyVisualTransition({
+		baseTransform,
+		transition: node.params.transition,
+		localTime,
+		duration: node.params.duration,
+		canvasWidth: context.renderer.width,
+	});
 
 	return {
-		transform: resolveTransformAtTime({
-			baseTransform: node.params.transform,
-			animations: node.params.animations,
-			localTime,
-		}),
-		opacity: resolveOpacityAtTime({
-			baseOpacity: node.params.opacity,
-			animations: node.params.animations,
-			localTime,
-		}),
+		transform: transitionState.transform,
+		opacity: baseOpacity * transitionState.opacityMultiplier,
 		textColor: resolveColorAtTime({
 			baseColor:
 				typeof node.params.params.color === "string"
@@ -438,7 +462,9 @@ async function resolveBackdropSource({
 		const frame = await videoCache.getFrameAt({
 			mediaId: node.params.mediaId,
 			file: node.params.file,
-			time: mediaTimeToSeconds({ time: roundMediaTime({ time: sourceTimeTicks }) }),
+			time: mediaTimeToSeconds({
+				time: roundMediaTime({ time: sourceTimeTicks }),
+			}),
 		});
 		if (!frame) {
 			return null;
@@ -485,10 +511,9 @@ function resolveEffectLayerNode({
 	const motion = definition.motion?.evaluate({
 		effectParams: node.params.effectParams,
 		progress: sampleEasingBezier({
-			bezier:
-				BUILTIN_PRESETS.find(
-					(entry) => entry.id === node.params.effectParams.easing,
-				)?.value ?? [0.25, 0.1, 0.25, 1],
+			bezier: BUILTIN_PRESETS.find(
+				(entry) => entry.id === node.params.effectParams.easing,
+			)?.value ?? [0.25, 0.1, 0.25, 1],
 			x: clamp({
 				value: (time - node.params.timeOffset) / node.params.duration,
 				min: 0,
-- 
cgit v1.3.1