scenePrePass method

@override void scenePrePass(double deltaSeconds, [ bool ancestorsVisible = true ])

Walks this node's subtree once per frame to prepare it for rendering: ticks components and animation players and refreshes the RenderItems the render passes iterate.

Called by Scene.update and Scene.render; not normally called directly. deltaSeconds is the elapsed time since the previous tick. ancestorsVisible is whether every ancestor of this node is visible, and defaults to true for the root.

Implementation

@override
void scenePrePass(double deltaSeconds, [bool ancestorsVisible = true]) {
  // Components and the animation player tick in super, so the inverse is
  // written after it: a decal driven by its own component would otherwise
  // paint from last frame's transform while its box drew at this frame's.
  super.scenePrePass(deltaSeconds, ancestorsVisible);
  // The world transform can change without project() running (the node or an
  // ancestor moved), so the inverse is refreshed from it each frame.
  if (worldTransformVersion != _writtenTransformVersion) _writeParameters();
}