Release Notes 1.64.0

Migration guide

Backend changes

In this release, we have added the possibility to resolve a multi-sampled stencil texture region directly to a 1x MSAA color texture. Custom backend users have to implement the following:

• A command BC_ResolveAndCopyStencilRegion, which resolves the stencil of a source depth-stencil texture onto a 1x MSAA destination texture (e.g. by using a compute shader)
• A newly added backend capability SupportsDepthStencilResolve indicating whether the backend supports BC_ResolveAndCopyStencilRegion
• A new Texture2D property IsUnorderedAccessEnabled when creating color textures, which indicates that the texture should be bindable as a "random access texture"
• A new DepthStencilTexture property IsShaderResource when creating depth-stencil textures, which indicates that the texture could be sampled from in a shader
• The render target could be an invalid handle now, indicating that only a depth-stencil resource should be bound

Changelog

Version 1.64.0

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Released 04 Mar 2025

Feature	Optimized SynchronizeModels significantly by computing some of complex expressions in the attributes directly, without compiling and invoking a JavaScript function
Enhancement	Improved error message for engine.call to include the name of the function when there is no handler for it
Enhancement	Improved performance of UnregisterDataBindAttributes() for pages with a lot of data-binding attributes used
Enhancement	Modified the Components sample to use Shadow DOM
Enhancement	Optimized layout for deep DOM structures with automatically sized children
Enhancement	Optimized text layout performance and memory usage
Enhancement	Improved error messages when data binding expression fails to parse or compile
Enhancement	Added support for multiple keyframe rules with the same name
Enhancement Unreal Engine	Added a delegate for mouse wheel event in HUD setups
Enhancement Unreal Engine	Added sharing of depth stencil textures for views with compatible dimensions to save texture memory
Enhancement	Refactor backends to standardize the storing of GPU objects
Enhancement	Added profiling data and documentation for handling bad cases for the flex layout algorithm
Enhancement	Added the possibility to directly resolve a multi-sampled stencil texture region to 1xMSAA color texture for DirectX 11,12, and PlayStation rendering backends
Fix	Fixed child element transitions not triggering after the hidden parent becomes visible
Fix	Updated the TypeScript definitions for the cohtml.js
Fix Unity	Added Dispose method for the CohtmlLogHandler
Fix Unity	Fixed Unity 6 treating UPM packages as experimental
Fix	Disabled emitting of some profile events when Library::EnableProfiling is disabled
Fix	Fixed a visual artifact when applying backdrop filter to the whole viewport
Fix	Fixed visual artefacts of left over text when changing the text dynamically in an inline container
Fix	Fixed crash when accessing unreachable array element with the safe binding enabled
Fix	Fixed animations sometimes failing to pause or wrongly resuming
Fix	Keyframe rules no longer pass the shadow DOM boundary
Fix	CSS animations now stop once their keyframe rule is removed
Fix Unreal Engine	Fixed unsafe access of texture when texture draws tracking is enabled on console platforms
Fix Unreal Engine	Fixed issues when recording screenshots with Inspector profiling
Fix Unreal Engine	Fixed assert when resolving MSAA render targets on some mobile devices
Fix Unreal Engine	Fixed a crash on older android devices related to unsupported shader buffer sizes
Fix	Fixed cases where scissor rect would be bigger than than the viewport
Fix	Fixed a crash when UnregisterModel with arrays when safe binding is enabled
Fix	Fixed a crash when a precompiled script throws an exception
Fix	Fixed binding of nested maps and arrays when safe binding is enabled
Fix Unreal Engine	Fixed assert during shader compilation on Mac OS when ShaderModel 6 is enabled
API	Added a new BC_ResolveAndCopyStencilRegion backend command and a SupportsDepthStencilResolve capability whether it can be used.