engine-info.md

Engine Backend & Feature Level Info

react-native-filament exposes three read-only getters from the underlying Filament engine that describe the GPU backend and its capabilities. These are useful for adaptive quality, diagnostics, and telemetry.

API

engine.getBackend()

Returns the resolved graphics backend as a string:

Value	Meaning
"metal"	Apple Metal (default on iOS/macOS)
"opengl"	OpenGL ES (default on Android)
"vulkan"	Vulkan (opt-in on Android/Linux/Windows)
"default"	Should not appear at runtime -- the engine always resolves to a concrete backend

engine.getSupportedFeatureLevel()

Returns the highest feature level the device's GPU supports, as an integer 0-3:

Level	Capabilities
0	OpenGL ES 2.0 features only
1	OpenGL ES 3.0 features (default on most modern devices)
2	OpenGL ES 3.1 + 16 texture units + cubemap arrays
3	OpenGL ES 3.1 + 31 texture units + cubemap arrays

On iOS with Metal, devices typically report feature level 3. On Android the level depends on the GPU -- budget GPUs may report 1, while mid-range and flagship GPUs report 2 or 3.

engine.getActiveFeatureLevel()

Returns the currently active feature level. This equals the supported level unless a lower level was explicitly set via Engine.Builder.featureLevel().

Example: Adaptive Quality

import { useFilamentContext } from 'react-native-filament';
import { useEffect } from 'react';

function AdaptiveScene() {
  const { engine } = useFilamentContext();

  useEffect(() => {
    const backend = engine.getBackend();
    const featureLevel = engine.getSupportedFeatureLevel();

    console.log(`Backend: ${backend}, Feature Level: ${featureLevel}`);

    // Use feature level as a GPU capability signal:
    //   Level 0-1: budget GPU -- use lower-poly models, fewer draw calls
    //   Level 2+:  capable GPU -- enable full-quality rendering
  }, [engine]);

  return (
    // ... your scene
  );
}

Example: Device Diagnostics Screen

import { useFilamentContext } from 'react-native-filament';
import { Text, View } from 'react-native';

function DiagnosticsPanel() {
  const { engine } = useFilamentContext();

  return (
    <View>
      <Text>Backend: {engine.getBackend()}</Text>
      <Text>Supported Feature Level: {engine.getSupportedFeatureLevel()}</Text>
      <Text>Active Feature Level: {engine.getActiveFeatureLevel()}</Text>
    </View>
  );
}

Background

Filament's C++ Engine class has always had getBackend(), getSupportedFeatureLevel(), and getActiveFeatureLevel() -- zero-cost const getters that return immediately. This change bridges them through the JSI layer so they are accessible from JavaScript, following the same EngineImpl -> EngineWrapper -> TypeScript pattern used by all other Engine methods.