When upgrading projects from Unity 5.3 to Unity 5.4, there are some changes you should be aware of which may affect your existing project.
Numerous changes to the Networking API.
WebRequest interface has been promoted from
UnityEngine.Networking. Unity 5.2 and 5.3 projects that use
UnityWebRequest will have to be updated.
An image effect with the
ImageEffectTransformsToLDR attribute will no longer be applied directly to the Scene view if found. A new attribute exists for applying effects to the Scene view:
ImageEffectAllowedInSceneView. The 5.4 Standard Assets have been upgraded to reflect this change.
A number of built-in shader variables were renamed for consistency:
The variable references will be automatically renamed in .shader and .cginc files when importing them. However, after the import the shaders will not be usable in Unity 5.3 or earlier, without manually renaming the variables.
In Unity 5.4, the way arrays of shader properties are handled has changed. Now there is “native” support for float/vector/matrix arrays in shaders (via
Shader.SetGlobalFloatArray etc.). These new APIs allow arrays up to 1,023 elements.
The old way of using number-suffixed names for referring to individual array elements is deprecated (e.g.
_Colors1) in both
MaterialPropertyBlock. Properties of this kind, serialized with the
Material are no longer able to set array elements (but if any uniform array’s name is suffixed by a number it still works).
The default shader compilation target has changed to “#pragma target 2.5” (SM3.0 on DX9, DX11 9.3 feature level on WinPhone). You can still target DX9 SM2.0 and DX11 9.1 feature level with “#pragma target 2.0”.
The majority of built-in shaders target 2.5 now: Notable exceptions are Unlit, VertexLit and fixed function shaders. In practice, this means that most of built-in shaders and newly-created shaders, by default, will not work on PC GPUs that are made before 2004. See this blog post for details.
Material class constructor
Material(string), which was already deprecated, stops working in 5.4. Using it will print an error and result in the magenta error shader.
The internal shader used to compute screen-space directional light shadows has moved to the Graphics settings. If you were using a customized version of directional light shadows by having a copy of that shader in your project, it will no longer be used. Instead, select your custom shader under Edit > Project Settings, then select the Graphics category.
Reflection probes share a sampler between the two textures. If you are sampling them manually in your shader, and get an “undeclared identifier samplerunity_SpecCube1” error, you’ll need to change code from
UnityEditor.ShaderUtil.ShaderPropertyTexDim is deprecated; use
The data layout of ComputeBuffers in automatically-converted OpenGL shaders has changed to match the layout of DirectX ComputeBuffers. If you use ComputeBuffers in OpenGL, remove any code that tweaks the data to match the previous OpenGL-specific layout rules. Please see Compute Shaders for more information.
Playables are now structs instead of classes.
Playable structs are handles to native
Playable classes, instead of pointers to native
Playable struct doesn’t guarantee that the Playable is usable. Use the
.IsValid method to verify that your Playable can be used.
Any method that used to return null for empty inputs/outputs will now return
Playable.Null is an invalid Playable.
Playable.Null can be passed to
SetInputs to reserve empty inputs, or to implicitly disconnect connected inputs.
Playable.Null or any invalid Playable as an input to any method, or calling a method on an invalid Playable will throw appropriate exceptions for the operation.
Comparing Playables with
null is now meaningless. Compare with
Playables must be allocated using the
Create static method of the class you wish to use.
Playables must be de-allocated using the
.Destroy method on the Playable handle.
Playables that are not de-allocated will leak.
Playables were converted to structs to improve performance by avoiding boxing/unboxing (more info on boxing).
Playable to an object, implicitly or explicitly, will cause boxing/unboxing, thus reducing performance.
Inheriting from a Playable class will cause boxing/unboxing of instances of the child class.
Since only animation is available for now,
ScriptPlayables have been replaced by
It is no longer possible to derive from base Playables. Simply aggregate Playables in your custom Playables.
Follow these instructions to upgrade your Oculus VR project from Unity 5.3:
Re-enable virtual reality support.
Remove Oculus Spatializer.
There has been a change to the events that are triggered when sibling GameObjects are re-ordered in Unity 5.4. Sibling GameObjects are GameObjects which all share the same parent in the Hierarchy window. In prior versions of Unity, changing the order of sibling GameObjects would cause every sibling to receive an
OnTransformParentChanged call. In 5.4, the sibling GameObjects no longer get this call. Instead, the parent GameObject receives a single call to
This means that if you have code in your project that relies on OnTransformParentChanged being called when siblings are re-ordered, these calls will no longer occur, and you need to update your code to take action when the parent object receives the OnTransformChildrenChanged call instead.
This changed because the new behavior gives improved performance.
Due to optimisations in the Transform component, using
Destroying parts of hierarchies involving 1000+ GameObjects may now take a long time. Calling
SetParent on or otherwise rearranging such large hierarchies at runtime is not recommended.
The generated Visual Studio project format was updated for all .NET scripting backend SDKs. This fixes excessive rebuilding when nothing has changed in the generated project. You might need to delete your existing generated *.csproj, especially if it was built with the “Generate C# projects” option checked, so Unity can regenerate it.
There are two new script serialization errors to catch when the Unity API is being called from constructors and field initializers during deserialization (loading). Deserialization might happen on a different thread to the main thread and it is therefore not safe to call the Unity API during deserialization. There are more details at the bottom of the (Script Serialization)[script-Serialization] page in the Unity Manual.
The editor now supports Retina resolutions on Mac OS X with high-resolution text, UI and 3D views.
The Editor GUI is now defined in point space rather than pixel space. On standard resolution displays, there is no change because each point is one pixel. On Retina displays, however, every point is two pixels. The current screen to UI scale is available as
EditorGUIUtility.pixelsPerPoint. Since Unity can have multiple windows, each on monitors with different pixel densities, this value might change between views.
If your editor code uses regular Editor/GUI/Layout methods, it is quite likely that you will not need to change anything.
If you are using
Screen.width/height, switch to
EditorWindow.position.width/height instead. This is because screen size is measured in pixels, but UI is defined in points. For custom Editors displaying in the Inspector, use
EditorGUIUtility.currentViewWidth, which properly accounts for the presence of a scroll bar.
If you are displaying other content in your UI, such as a RenderTexture, you are probably calculating its size in points. To support Retina resolutions, you will need to convert your point sizes to pixel sizes. There are new methods in EditorGUIUtility for this.
If you are using GUIStyles with custom backgrounds, you can add Retina versions of background textures by putting one texture with exactly doubled dimensions into a ‘GUIStyleState.scaledBackgrounds’ array.
Macs with underpowered graphics hardware may experience unacceptably slow editor frame rates in 3D views due to increased resolution. Retina support can be disabled by choosing “Get Info” on Unity.app in the Finder, and checking “Open in Low Resolution”.
The 5.3 behavior is that the animation system always sends Transform update messages for animation curves which are constant. These messages wake up the Rigidbodies and fixing this proved very risky in 5.3.
The 5.4 behavior is that if there are no position changes, the Rigidbody does not wake up (as most people would expect).
If your project relies on the 5.3 behavior of waking Rigidbody all the time, it might not work as expected in 5.4.
The Unity Web Player target has been dropped from Unity 5.4. If you upgrade your project to 5.4, you will not be able to deploy it to the Web Player platform.
If you have legacy Web Player projects that you need to maintain, do not upgrade them to 5.4 or later.