3D Stands

A stand is any FMX style item, so it can contain a 3D scene: a TViewport3D with a TLayer3D inside shows a 2D frame on a plane in a 3D space, which you can rotate, move and animate like any 3D object. demos\Stand3D shows two such stands, stand3D and new3D.

TLayout 'new3D'                         Align = Contents
└── TViewport3D                         Align = Client
    └── TLayer3D 'layer3D'              Align = Client
        ├── TRectangle 'rectangle'
        │   └── TLayout 'container'     ← the frame goes on the 3D layer
        ├── TFloatAnimation             OnShow*: PropertyName = RotationAngle.X
        └── TFloatAnimation             OnHide*: PropertyName = RotationAngle.X

The other stand of the demo, stand3D, uses the TLayer3D itself as container, inside a TDummy, with its own TCamera named camera in a second TDummy.

The frame is placed, as usual, in the container element, which here is inside the TLayer3D: it keeps working as a normal 2D frame, with mouse and touch input.

A 3D object can also be the parent of an ordinary stand: FrameStand1.New<TMyFrame>(Layer3D1) puts the stand on the 2D surface of a TLayer3D, and a TFrameStand dropped on a TForm3D uses the form as default parent.

Wiring the scene

Some 3D settings cannot be expressed in the style and must be applied to each clone. The OnBeforeShow event of the component is the place for them, for example to make the viewport use the camera of the stand:

procedure TMainForm.FrameStand1BeforeShow(const ASender: TSubjectStand;
  const ASubjectInfo: TSubjectInfo);
var
  LViewport: TViewport3D;
begin
  if ASubjectInfo.StandStyleName = 'stand3D' then
  begin
    LViewport := ASubjectInfo.Stand.Children[0] as TViewport3D;  // the root's first child
    LViewport.Camera := ASubjectInfo.Stand.FindStyleResource('camera') as TCamera;
    LViewport.UsingDesignCamera := False;
  end;
end;

The demo also realigns the TLayer3D when the form is resized, to work around an FMX issue with TLayer3D alignment (RSP-18282).