[UE4]Performance Guidelines for Mobile Devices
keywords: Mobile Performance Optimization, Official Documents
Use Full Precision
The Material Editor contains a section called Mobile, which has two properties:
Use Full Precisionand
Use Lightmap Directionality. These are intended for mobile devices and to save performance. By default, Unreal will use less-precise math in order to save on memory and computation time. When enabled, the
Use Full Precisionproperty will use the highest precision available on a mobile device. This will solve certain rendering issues at the cost of being more expensive to use. Generally, you’ll leave this property disabled unless you notice issues with how the material looks.
Use Lightmap Directionality
Use Lightmap Directionality, has an effect that is very apparent when using a normal map. Basically, it will use the lightmap to show the light at the top of the normal map and shadows at the bottom. You’ll need to
Buildthe project in order to see the lightmap information being used. If disabled, lighting from lightmaps will be flat but cheaper.
Materialsection contains the
Fully Roughproperty that, when enabled, will ignore the
Roughnesschannel and instead force the material to be completely rough. This will save a number of instructions for optimization’s sake and reduce one texture sampler.
High Quality Reflections
Forward Shadingsection contains the
High Quality Reflectionsproperty which, when disabled, can increase the number of texture samples you can use by two. Turning this off will remove them to instead be used for cubemaps to display reflections.
While some of these properties will have less quality than the traditional fully-formed
material, the settings can reduce the number of instructions on the
vertex shader and the
Texture samplers used, which you can see from the
Stats toolbar from the Material Editor.
Quoted from [Unreal Engine 4 Shaders and Effects Cookbook] Chapter 8 Mobile Shaders and Material Optimization
1, Dithered LOD Transitions support on Mobile, but it would increase rendering overhead.
1, Disable HDR on mobile if frame rate is low, otherwise image would be blur when camera transforming. But Lighting effect would lose violently if HRD disabled.
Offical Docs: Mobile Game Development
Mobile Game Development
Materials on Mobile
Materials for Mobile Platforms
Performance on Mobile
Mobile Performance Tips and Tricks
Performance Guidelines for Mobile Devices