Mobile rendering limitations

See also

The general 3D rendering limitations also apply to mobile platforms.

To improve out-of-the-box performance on mobile devices, Redot automatically uses low-end-friendly settings by default on both Android and iOS. These are configured by project settings with a .mobile feature tag suffix.

One of the most notable changes on mobile that will affect 3D projects is that lighting is done per-vertex instead of per-pixel. This improves performance a lot, but can break rendering in some scenes, especially if your meshes aren't sufficiently subdivided for per-vertex lighting to look good. This can be disabled in the Project Settings at a performance cost (see below).

When using GLES2, some custom shaders may break when exporting to Android. This is caused by a lower shader precision being used by default to improve performance. You can force high precision on all shader computations by enabling rendering/gles2/compatibility/enable_high_float.Android project setting, but this has a significant performance cost and won't work on all devices.

The following project settings have mobile-specific overrides:

Setting	Desktop default	Mobile default
rendering/quality/directional_shadow/size	4096	2048
rendering/quality/intended_usage/framebuffer_allocation	3D	3D Without Effects
rendering/quality/lightmapping/use_bicubic_sampling	true	false
rendering/quality/reflections/high_quality_ggx	true	false
rendering/quality/shading/force_blinn_over_ggx	false	true
rendering/quality/shading/force_lambert_over_burley	false	true
rendering/quality/shading/force_vertex_shading	false	true
rendering/quality/shadow_atlas/size	4096	2048
rendering/quality/shadows/filter_mode	PCF5	Disabled
GLES3 only: rendering/gles3/shaders/max_simultaneous_compiles	2	1
GLES3 only: rendering/gles3/shaders/shader_cache_size_mb	512	128
GLES3 only: rendering/quality/depth/hdr	true	false
GLES3 only: rendering/quality/reflections/texture_array_reflections	true	false

See the ProjectSettings class documentation for more information on those setting overrides.

If you're only targeting mobile platforms in your project, consider changing the project settings' values to match the mobile overrides. This way, you'll get a preview that is closer to the mobile appearance when running the project on a desktop platform (as well as within the editor).

Warning

Due to driver bugs, GLES3 support on Android and iOS can be poor, especially on old or low-end devices. Therefore, it is recommended to use the GLES2 renderer when targeting mobile platforms (especially Android).

You can change the rendering backend in the Project Settings (Rendering > Quality > Driver > Driver Name).