Instead of displaying Texture2Ds, present the RenderTexture directly to the window:

- Previously, we copied the texture from the GPU into a Texture2D to display it.
- Now, we instantiate as many different RenderTexture as necessary and display those instead.

Author: hai-vr

Packages/dev.hai-vr.lightbox-viewer/Scripts/Editor/LightboxViewerGenerator.cs

@@ -19,6 +19,7 @@ public class LightboxViewerGenerator
         private GameObject _animatedRoot;
         private Camera _camera;
         private Material _material;
+        private bool _needsCounterRoll;
 
         public void Begin(GameObject animatedRoot, float customRoll, bool counterRotate, Camera cameraOptional, bool usePostProcessing)
         {
@@ -29,6 +30,7 @@ public void Begin(GameObject animatedRoot, float customRoll, bool counterRotate,
                 _material = new Material(Shader.Find("Hai/LightboxViewerCounterRoll"));
                 _material.SetFloat("_CounterRoll", -customRoll / 180f);
             }
+            _needsCounterRoll = isCustomRollSlanted && counterRotate;
 
             Profiler.BeginSample("LightboxViewer.Generator.Begin.AddCameraComponent");
             _camera = cameraOptional != null ? Object.Instantiate(cameraOptional) : new GameObject().AddComponent<Camera>();
@@ -65,7 +67,7 @@ public void Terminate()
             Object.DestroyImmediate(_camera.gameObject);
         }
 
-        public void RenderNoAnimator(Texture2D element, GameObject currentLightbox, RenderTexture renderTexture, Vector3 referentialVector, Quaternion referentialQuaternion, float verticalDisplacement)
+        public void RenderNoAnimator(Texture element, GameObject currentLightbox, RenderTexture renderTexture, Vector3 referentialVector, Quaternion referentialQuaternion, float verticalDisplacement)
         {
             var rootTransform = _animatedRoot.transform;
             var camTransform = _camera.transform;
@@ -83,16 +85,34 @@ public void RenderNoAnimator(Texture2D element, GameObject currentLightbox, Rend
                 camTransform.rotation = currentLightbox.transform.rotation * referentialQuaternion * camTransform.rotation;
                 rootTransform.rotation = currentLightbox.transform.rotation * referentialQuaternion * rootTransform.rotation;
 
-                renderTexture.wrapMode = TextureWrapMode.Clamp;
-
-                RenderCamera(renderTexture, _camera);
-                if (SystemInfo.supportsAsyncGPUReadback && !DoNotUseAsyncReadback)
+                if (element is RenderTexture rt)
                 {
-                    AsyncRenderTextureTo(renderTexture, element);
+                    RenderCamera(rt, _camera);
+                    if (_needsCounterRoll && _material != null)
+                    {
+                        var diff = RenderTexture.GetTemporary(rt.width, rt.height, 24);
+                        Graphics.Blit(rt, diff);
+                        
+                        _material.SetTexture("_MainTex", diff);
+                        var ratio = rt.width / (float)rt.height;
+                        _material.SetFloat("_Ratio", ratio);
+                        Graphics.Blit(diff, rt, _material);
+                        
+                        RenderTexture.ReleaseTemporary(diff);
+                    }
                 }
-                else
+                else if (false)
                 {
-                    SyncRenderTextureTo(renderTexture, element);
+                    renderTexture.wrapMode = TextureWrapMode.Clamp;
+                    RenderCamera(renderTexture, _camera);
+                    if (SystemInfo.supportsAsyncGPUReadback && !DoNotUseAsyncReadback)
+                    {
+                        AsyncRenderTextureTo(renderTexture, element as Texture2D);
+                    }
+                    else
+                    {
+                        SyncRenderTextureTo(renderTexture, element as Texture2D);
+                    }
                 }
             }
             finally

Packages/dev.hai-vr.lightbox-viewer/Scripts/Editor/LightboxViewerRenderQueue.cs

@@ -19,12 +19,12 @@ public class LightboxViewerRenderQueue
 
         internal const bool WhenInEditMode_DoNotDisableMainAvatar = true;
 
-        private readonly Dictionary<int, Texture2D> _lightboxIndexToTexture;
+        private readonly Dictionary<int, Texture> _lightboxIndexToTexture;
         private readonly Queue<int> _queue;
         private int _queueSize;
         private Scene _openScene;
         private bool _sceneLoaded;
-        private Texture2D[] _textures = new Texture2D[1];
+        private Texture[] _textures = new Texture[1];
         private string[] _names = new string[1];
         private int _width = 512;
         private int _height = 512;
@@ -71,11 +71,11 @@ public void EnableDepthTexture(bool enableDepthTexture, GameObject depthEnabler)
 
         public LightboxViewerRenderQueue()
         {
-            _lightboxIndexToTexture = new Dictionary<int, Texture2D>();
+            _lightboxIndexToTexture = new Dictionary<int, Texture>();
             _queue = new Queue<int>();
         }
 
-        private Texture2D RequireRender(int lightboxIndex, int width, int height)
+        private Texture RequireRender(int lightboxIndex, int width, int height)
         {
             if (_lightboxIndexToTexture.ContainsKey(lightboxIndex)
                 && _lightboxIndexToTexture[lightboxIndex] != null // Can happen when the texture is destroyed (Unity invalid object)
@@ -89,7 +89,11 @@ private Texture2D RequireRender(int lightboxIndex, int width, int height)
                 return _lightboxIndexToTexture[lightboxIndex];
             }
 
-            var texture = new Texture2D(width, height, TextureFormat.RGB24, false);
+            if (_lightboxIndexToTexture.ContainsKey(lightboxIndex))
+            {
+                Object.DestroyImmediate(_lightboxIndexToTexture[lightboxIndex]);
+            }
+            var texture = new RenderTexture(width, height, 0, RenderTextureFormat.ARGB32);
             _lightboxIndexToTexture[lightboxIndex] = texture; // TODO: Dimensions
 
             _queue.Enqueue(lightboxIndex);
@@ -423,7 +427,7 @@ private void TrueRender(GameObject copy)
                 }
 
                 var itemCount = 0;
-                var renderTexture = RenderTexture.GetTemporary(_lightboxIndexToTexture[0].width, _lightboxIndexToTexture[0].height, 24);
+                RenderTexture renderTexture = null;
                 var allApplicableLightboxes = AllApplicableLightboxes();
                 while (_queue.Count > 0 && itemCount < _queueSize)
                 {
@@ -438,7 +442,6 @@ private void TrueRender(GameObject copy)
                         itemCount++;
                     }
                 }
-                RenderTexture.ReleaseTemporary(renderTexture);
             }
             finally
             {
@@ -501,7 +504,7 @@ public void ForceRequireRenderAll()
             var lightboxes = AllApplicableLightboxes();
             if (_textures.Length != lightboxes.Length)
             {
-                _textures = new Texture2D[lightboxes.Length];
+                _textures = new Texture[lightboxes.Length];
                 _names = new string[lightboxes.Length];
             }
             for (var i = 0; i < lightboxes.Length; i++)