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Fix subtitles distorted by BopVisualEffects post-processing #14

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Merged
Brollyy merged 4 commits into from
Mar 23, 2026
Merged

Fix subtitles distorted by BopVisualEffects post-processing #14

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92eae8c
Initial plan
Copilot Mar 18, 2026
465ff6d
Fix: keep subtitle canvas in ScreenSpaceOverlay to avoid BopVisualEff…
Copilot Mar 18, 2026
adbb452
Fix editor viewport: use dedicated overlay camera instead of ScreenSp…
Copilot Mar 18, 2026
852db23
Fixed issues with the subs not showing up and not tracking camera cor…
Brollyy Mar 23, 2026
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51 changes: 49 additions & 2 deletions BopSubtitleReader/Core/SubtitleRuntimeController.cs
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Original file line number Diff line number Diff line change
Expand Up @@ -39,6 +39,7 @@ public sealed class SubtitleRuntimeController : MonoBehaviour
private int _cachedActiveSegmentIndex = -1;
private float _cachedKaraokeBeat = float.NaN;
private Camera? _cachedSubtitleCamera;
private CameraViewportState? _cachedSubtitleViewportState;
private float _nextCameraResolveTime;
private const float CameraResolveIntervalSeconds = 0.5f;
public bool HasActiveSession => _track is not null && _loader is not null && _config is not null;
Expand Down Expand Up @@ -71,6 +72,7 @@ public void StartSession(MixtapeLoaderCustom loader, SubtitleTrack track, Subtit
_cachedActiveSegmentIndex = -1;
_cachedKaraokeBeat = float.NaN;
_cachedSubtitleCamera = null;
_cachedSubtitleViewportState = null;
_nextCameraResolveTime = 0f;
RefreshSubtitleCamera(force: true);
_overlay.Hide();
Expand All @@ -90,6 +92,7 @@ public void StopSession()
_cachedActiveSegmentIndex = -1;
_cachedKaraokeBeat = float.NaN;
_cachedSubtitleCamera = null;
_cachedSubtitleViewportState = null;
_nextCameraResolveTime = 0f;
_overlay.Hide();
}
Expand Down Expand Up @@ -290,10 +293,15 @@ private void RefreshSubtitleCamera(bool force = false)
}

var resolvedCamera = ResolveSubtitleCamera(_loader);
if (force || !ReferenceEquals(_cachedSubtitleCamera, resolvedCamera))
var resolvedViewportState = CameraViewportState.Capture(resolvedCamera);
var cameraChanged = !ReferenceEquals(_cachedSubtitleCamera, resolvedCamera);
var viewportChanged = !_cachedSubtitleViewportState.HasValue
|| !CameraViewportState.AreEquivalent(_cachedSubtitleViewportState.Value, resolvedViewportState);
if (force || cameraChanged || viewportChanged)
{
_cachedSubtitleCamera = resolvedCamera;
_overlay.SetCamera(resolvedCamera);
_cachedSubtitleViewportState = resolvedViewportState;
_overlay.SetReferenceCamera(resolvedCamera);
}

_nextCameraResolveTime = Time.unscaledTime + CameraResolveIntervalSeconds;
Expand Down Expand Up @@ -630,4 +638,43 @@ private static string Truncate(string value, int max)
return value.Substring(0, max) + "...";
}

private readonly struct CameraViewportState
{
public CameraViewportState(Rect rect, Rect pixelRect, RenderTexture? targetTexture)
{
Rect = rect;
PixelRect = pixelRect;
TargetTexture = targetTexture;
}

public Rect Rect { get; }
public Rect PixelRect { get; }
public RenderTexture? TargetTexture { get; }

public static CameraViewportState Capture(Camera? camera)
{
return camera is null
? new CameraViewportState(
new Rect(0f, 0f, 1f, 1f),
new Rect(0f, 0f, Screen.width, Screen.height),
null)
: new CameraViewportState(camera.rect, camera.pixelRect, camera.targetTexture);
}

public static bool AreEquivalent(CameraViewportState left, CameraViewportState right)
{
return AreRectsApproximatelyEqual(left.Rect, right.Rect)
&& AreRectsApproximatelyEqual(left.PixelRect, right.PixelRect)
&& ReferenceEquals(left.TargetTexture, right.TargetTexture);
}

private static bool AreRectsApproximatelyEqual(Rect a, Rect b)
{
return Mathf.Approximately(a.x, b.x)
&& Mathf.Approximately(a.y, b.y)
&& Mathf.Approximately(a.width, b.width)
&& Mathf.Approximately(a.height, b.height);
}
}

}
70 changes: 45 additions & 25 deletions BopSubtitleReader/Core/TmpSubtitleOverlay.cs
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Original file line number Diff line number Diff line change
Expand Up @@ -11,11 +11,12 @@ namespace BopSubtitleReader.Core;
public sealed class TmpSubtitleOverlay
{
private static readonly ClassLogger Log = ClassLogger.GetForClass<TmpSubtitleOverlay>();
private const int UiLayer = 5; // Unity built-in "UI" layer

private bool _initializationAttempted;
private bool _available;
private GameObject? _host;
private Canvas? _canvas;
private Camera? _overlayCamera;
private TextMeshProUGUI? _tmpText;
private RectTransform? _tmpRect;
private GameObject? _karaokeLayer;
Expand Down Expand Up @@ -121,37 +122,33 @@ public void Hide()
}
}

public void SetCamera(Camera? camera)
/// <summary>
/// Syncs the subtitle overlay camera's viewport to match <paramref name="referenceCamera"/>'s
/// viewport rect so that subtitles are confined to the same on-screen area (important when
/// the game camera is not full-screen, e.g. in the Bits &amp; Bops editor).
/// Pass <c>null</c> to reset to a full-screen viewport.
/// </summary>
public void SetReferenceCamera(Camera? referenceCamera)
{
if (!EnsureInitialized() || _canvas is null)
if (!EnsureInitialized() || _overlayCamera is null)
{
return;
}

if (camera is not null)
if (referenceCamera is null)
{
if (_canvas.renderMode != RenderMode.ScreenSpaceCamera)
{
_canvas.renderMode = RenderMode.ScreenSpaceCamera;
}

if (!ReferenceEquals(_canvas.worldCamera, camera))
{
_canvas.worldCamera = camera;
}

_overlayCamera.targetDisplay = 0;
_overlayCamera.targetTexture = null;
_overlayCamera.rect = new Rect(0f, 0f, 1f, 1f);
_overlayCamera.pixelRect = new Rect(0f, 0f, Screen.width, Screen.height);
return;
}

if (_canvas.renderMode != RenderMode.ScreenSpaceOverlay)
{
_canvas.renderMode = RenderMode.ScreenSpaceOverlay;
}

if (_canvas.worldCamera is not null)
{
_canvas.worldCamera = null;
}
// Mirror display + render target so subtitles render in the same output surface as gameplay.
_overlayCamera.targetDisplay = referenceCamera.targetDisplay;
_overlayCamera.targetTexture = referenceCamera.targetTexture;
_overlayCamera.rect = referenceCamera.rect;
_overlayCamera.pixelRect = referenceCamera.pixelRect;
}
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private bool EnsureInitialized()
Expand All @@ -168,15 +165,33 @@ private bool EnsureInitialized()

_initializationAttempted = true;

// Create a dedicated overlay camera for the subtitle canvas.
// Using a separate camera (not the game camera) prevents any post-processing effects
// such as BopVisualEffects from being applied to the subtitle canvas.
// Using ScreenSpaceCamera (rather than ScreenSpaceOverlay) ensures the canvas viewport
// tracks the game camera's viewport rect, which is important in the editor where the
// game view is not full-screen.
var cameraHost = new GameObject("BOP_SubtitleCameraHost");
Object.DontDestroyOnLoad(cameraHost);
var overlayCamera = cameraHost.AddComponent<Camera>();
overlayCamera.clearFlags = CameraClearFlags.Depth;
overlayCamera.cullingMask = 1 << UiLayer; // Render only the UI layer for the subtitle canvas
overlayCamera.depth = 100; // Render after the main game camera
overlayCamera.rect = new Rect(0f, 0f, 1f, 1f);
_overlayCamera = overlayCamera;

var canvasObject = new GameObject("BOP_SubtitleCanvas");
Object.DontDestroyOnLoad(canvasObject);
// Place on the UI layer so that game-world cameras cannot accidentally render it.
canvasObject.layer = UiLayer;

var canvas = canvasObject.AddComponent<Canvas>();
canvas.renderMode = RenderMode.ScreenSpaceOverlay;
canvas.renderMode = RenderMode.ScreenSpaceCamera;
canvas.worldCamera = overlayCamera;
canvas.sortingOrder = 100;
_canvas = canvas;

var textObject = new GameObject("BOP_SubtitleText");
textObject.layer = UiLayer;
textObject.transform.SetParent(canvasObject.transform, false);

var rect = textObject.AddComponent<RectTransform>();
Expand Down Expand Up @@ -538,6 +553,7 @@ private void ApplyOutline(TextMeshProUGUI text, Color outlineColor, float outlin
}

_karaokeLayer = new GameObject("BOP_KaraokeLayer");
_karaokeLayer.layer = UiLayer;
_karaokeLayer.transform.SetParent(_tmpText.transform, false);
var rect = _karaokeLayer.AddComponent<RectTransform>();
rect.anchorMin = new Vector2(0f, 0f);
Expand All @@ -557,6 +573,7 @@ private void ApplyOutline(TextMeshProUGUI text, Color outlineColor, float outlin
}

var rootGo = new GameObject($"KaraokeSeg_{_karaokeTextPool.Count:D2}");
rootGo.layer = UiLayer;
rootGo.transform.SetParent(_karaokeLayer.transform, false);
var rootRect = rootGo.AddComponent<RectTransform>();
rootRect.anchorMin = new Vector2(0.5f, 0.5f);
Expand All @@ -565,6 +582,7 @@ private void ApplyOutline(TextMeshProUGUI text, Color outlineColor, float outlin
rootRect.anchoredPosition = Vector2.zero;

var baseGo = new GameObject("Base");
baseGo.layer = UiLayer;
baseGo.transform.SetParent(rootGo.transform, false);
var baseRect = baseGo.AddComponent<RectTransform>();
baseRect.anchorMin = new Vector2(0f, 0f);
Expand All @@ -581,6 +599,7 @@ private void ApplyOutline(TextMeshProUGUI text, Color outlineColor, float outlin
}

var maskGo = new GameObject("FillMask");
maskGo.layer = UiLayer;
maskGo.transform.SetParent(rootGo.transform, false);
var maskRect = maskGo.AddComponent<RectTransform>();
maskRect.anchorMin = new Vector2(0f, 0f);
Expand All @@ -590,6 +609,7 @@ private void ApplyOutline(TextMeshProUGUI text, Color outlineColor, float outlin
maskGo.AddComponent<RectMask2D>();

var fillGo = new GameObject("Fill");
fillGo.layer = UiLayer;
fillGo.transform.SetParent(maskGo.transform, false);
var fillRect = fillGo.AddComponent<RectTransform>();
fillRect.anchorMin = new Vector2(0f, 0f);
Expand Down
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