update method

@override void update(double deltaSeconds)

Called once per frame while the component is mounted, enabled, and loaded. deltaSeconds is the elapsed time since the previous tick. A traversal visits each component at most once. Removing this component or an earlier sibling is safe. A component inserted before the current traversal position starts on the next frame. Reordering component or child lists during traversal is unsupported.

Implementation

@override
void update(double deltaSeconds) {
  if (timeSpeed != 0.0 && deltaSeconds > 0.0) {
    timeOfDay = (timeOfDay + timeSpeed * deltaSeconds) % 24.0;
  }

  final sunDir = sunDirection;
  if (skySource != null) {
    skySource!.sunDirection = sunDir;
  }

  final targetNode =
      sunLightNode ??
      node.children.cast<Node?>().firstWhere(
        (c) => c?.getComponent<DirectionalLightComponent>() != null,
        orElse: () => null,
      );

  if (targetNode == null) return;

  final eye = sunDir * 100.0;
  final target = vm.Vector3.zero();

  // In flutter_scene, DirectionalLightComponent travels along local +Z
  final forward = (target - eye).normalized();
  var up = vm.Vector3(0, 1, 0);
  if (up.cross(forward).length2 < 1e-6) {
    up = vm.Vector3(0, 0, 1);
  }
  final right = up.cross(forward).normalized();
  final actualUp = forward.cross(right).normalized();

  final worldMat = vm.Matrix4.columns(
    vm.Vector4(right.x, right.y, right.z, 0.0),
    vm.Vector4(actualUp.x, actualUp.y, actualUp.z, 0.0),
    vm.Vector4(forward.x, forward.y, forward.z, 0.0),
    vm.Vector4(eye.x, eye.y, eye.z, 1.0),
  );

  final parent = targetNode.parent;
  if (parent != null) {
    final invParent = parent.globalTransform.clone()..invert();
    targetNode.localTransform = invParent * worldMat;
  } else {
    targetNode.localTransform = worldMat;
  }

  if (applyLightingToTarget) {
    final lighting = evaluateLighting();
    final lightComp = targetNode.getComponent<DirectionalLightComponent>();
    if (lightComp != null) {
      lightComp.light.color = lighting.sunColor;
      lightComp.light.intensity = lighting.sunIntensity;
      lightComp.light.castsShadow = lighting.shadowDarkness > 0.0;
      lightComp.light.shadowAmbientStrength = (1.0 - lighting.shadowDarkness)
          .clamp(0.0, 1.0);
    }
    if (targetScene != null) {
      targetScene!.environmentIntensity = lighting.environmentIntensity;
    }
  }
}