Thursday, February 16th, 2017 Posted by Jim Thacker

Epic Games releases Unreal Engine 4.15


Unreal Engine 4.15 introduces support for HDR as well as LDR displays, as shown in these simulated images. Other changes to the game engine include improvements to texture streaming and post processing.


Epic Games has released Unreal Engine 4.15, the latest update to the game engine, improving texture streaming and post processing, and adding support for HDR displays and the upcoming Nintendo Switch.

Improved texture streaming and material editing
As usual, the changelog for the release runs to many thousands of words, but the changes most likely to affect artists directly are those affecting materials, rendering and animation.

In the first camp, texture streaming has been overhauled, with Epic claiming a 40% reduction in texture memory usage and a 2-3x increase in texture load times.

There are also three new view modes intended for debugging texture streaming performance.

The Material Editor gets support for Reroute nodes, enabling artists to organise node networks in ways that make them easier to read at a glance. The nodes function identically between Blueprints and the editor.



Texture artists can also now use pre-skinned local normals to achieve effects like automatic UV mapping onto skeletal meshes using locally aligned triplanar materials, as shown above.

New tonemapping and colour grading options
In the rendering and post-processing toolset, the newer ACES-compliant filmic tonemapper is now on by default, and bloom settings have been updated to provide a more physically correct result.

Epic says that it plans to remove the old tonemapper in a future release.

The colour grading controls in the Post Process settings have also been updated, with improved precision for the sliders and a new colour wheel to edit the X, Y and Z channels simultaneously.

Early support for HDR displays
There is now experimental support for HDR rendering to displays that support it, with the engine activating HDR output automatically when a suitable display is detected at launch.

There is also a system for matching the look of the HDR ouptput automatically to that of a LDR UI.

So far, HDR output put is only supported on Windows via Direct3D 11 – and then only on Nvidia GPUs – and on Macs via Metal. Support for other platforms is “coming in future releases”.



Artists working on mobile titles also get an improved viewport preview that emulates the feature set of Android devices running the OpenGL ES 3.1 or Vulkan APIs and iOS devices running Metal.

The update improves support for Metal in general, with UE4’s tessellation features now fully supported.

Other changes to mobile output include experimental support for monoscopic far field rendering, enabling VR applications to render distance objects in mono and nearby objects in stereo, improving performance.

Mobile devices can also now use the Custom Stencil mode for creating object outlines and similar effects.



Updated Blendspace Editor and other animation features
Animators get an update to the Blendspace Editor, updating its UI and standard workflows. You can see it in action above and find details of the specific changes via the link at the foot of the story.

Other changes include a new Modify Curve node for manipulating animation curves arbitrarily, particularly when creating dynamically driven animations; and the option to link animation curves to a particular bone in a skeletal rig so that they can be culled out when switching LODs.

There is also a new option to visualise an object’s centre of mass when debugging physics sims.



Updates to the Sequencer and VR editors
The new Sequencer cinematic editing toolset also gets an update, with support for animation blending, the option to use Sequencer components in Blueprints, and various UI and workflow updates.

The VR Editor gets a few new options, too, including redesigned in-editor radial menus and quick menus, and a new numerical input menu.

Support for the Nintendo Switch and new input peripherals
The range of devices supported by the engine has also been extended: most notably, adding Nintendo’s upcoming Switch console, but also mobile ARM64 devices running Linux.

New peripherals supported include the PlayStation VR Aim controller; steering wheel and flightstick devices; and there is also a new Force Feedback component for creating haptic effects.

Performance improvements and other changes
Other changes include improvements in C++ compilation speed – Epic says that it is now up to 50% faster – while ‘cooking’ Blueprints to C++ code is now officially a production-ready feature.

You can read a full list of changes and bugfixes via the link at the foot of the story.

Pricing and availability
Unreal Engine 4.15 is available for 64-bit Windows 7+, Mac OS X 10.10.5+ or Linux. Use of the editor is free, but Epic takes 5% of gross beyond the first $3,000 per quarter for any product you release commercially.


Read a full list of new features in Unreal Engine 4.15