int (*D3DRMUSERVISUALCALLBACK)(LPDIRECT3DRMUSERVISUAL lpD3DRMUV,
LPVOID lpArg, D3DRMUSERVISUALREASON lpD3DRMUVreason,
LPDIRECT3DRMDEVICE lpD3DRMDev, LPDIRECT3DRMVIEWPORT lpD3DRMview);
Alerts an application that supplies user-visual objects that it should execute the execute buffer. This function is application-defined.
·Returns TRUE if the lpD3DRMUVreason parameter is D3DRMUSERVISUAL_CANSEE and the user-visual object is visible in the viewport. Returns FALSE otherwise. If the lpD3DRMUVreason parameter is D3DRMUSERVISUAL_RENDER, the return value is application-defined. It is always safe to return TRUE.
lpD3DRMUV
Address of the Direct3DRMUserVisual object.
lpArg
Address of application-defined data passed to this callback function.
lpD3DRMUVreason
One of the members of the D3DRMUSERVISUALREASON enumerated type:
D3DRMUSERVISUAL_CANSEE
The application should return TRUE if the user-visual object is visible in the viewport. In this case, the application uses the device specified in the lpD3DRMview parameter.
D3DRMUSERVISUAL_RENDER
The application should render the user-visual element. In this case, the application uses the device specified in the lpD3DRMDev parameter.
lpD3DRMDev
Address of a Direct3DRMDevice object used to render the Direct3DRMUserVisual object.
lpD3DRMview
Address of a Direct3DRMViewport object used to determine whether the Direct3DRMUserVisual object is visible.
When determining the order in which to call callback functions, the system searches the objects highest in the hierarchy first, and then calls their callback functions in the order in which they were created.