Udostępnij za pośrednictwem

ATL_DRAWINFO Structure

  • Artykuł

 

The new home for Visual Studio documentation is Visual Studio 2017 Documentation on docs.microsoft.com.

The latest version of this topic can be found at ATL_DRAWINFO Structure.

Contains information used for rendering to various targets, such as a printer, metafile, or ActiveX control.

Syntax

struct ATL_DRAWINFO {
    UINT cbSize;
    DWORD dwDrawAspect;
    LONG lindex;
    DVTARGETDEVICE* ptd;
    HDC hicTargetDev;
    HDC hdcDraw;
    LPCRECTL prcBounds;
    LPCRECTL prcWBounds;
    BOOL bOptimize;
    BOOL bZoomed;
    BOOL bRectInHimetric;
    SIZEL ZoomNum;
    SIZEL ZoomDen;
};

Members

cbSize
The size of the structure, in bytes.

dwDrawAspect
Specifies how the target is to be represented. Representations can include content, an icon, a thumbnail, or a printed document. For a list of possible values, see DVASPECT and DVASPECT2.

lindex
Portion of the target that is of interest for the draw operation. Its interpretation varies depending on the value in the dwDrawAspect member.

ptd
Pointer to a DVTARGETDEVICE structure that enables drawing optimizations depending on the aspect specified. Note that newer objects and containers that support optimized drawing interfaces support this member as well. Older objects and containers that do not support optimized drawing interfaces always specify NULL for this member.

hicTargetDev
Information context for the target device pointed to by ptd from which the object can extract device metrics and test the device's capabilities. If ptd is NULL, the object should ignore the value in the hicTargetDev member.

hdcDraw
The device context on which to draw. For a windowless object, the hdcDraw member is in the MM_TEXT mapping mode with its logical coordinates matching the client coordinates of the containing window. In addition, the device context should be in the same state as the one normally passed by a WM_PAINT message.

prcBounds
Pointer to a RECTL structure specifying the rectangle on hdcDraw and in which the object should be drawn. This member controls the positioning and stretching of the object. This member should be NULL to draw a windowless in-place active object. In every other situation, NULL is not a legal value and should result in an E_INVALIDARG error code. If the container passes a non-NULL value to a windowless object, the object should render the requested aspect into the specified device context and rectangle. A container can request this from a windowless object to render a second, non-active view of the object or to print the object.

prcWBounds
If hdcDraw is a metafile device context (see GetDeviceCaps in the Windows SDK), this is a pointer to a RECTL structure specifying the bounding rectangle in the underlying metafile. The rectangle structure contains the window extent and window origin. These values are useful for drawing metafiles. The rectangle indicated by prcBounds is nested inside this prcWBounds rectangle; they are in the same coordinate space.

bOptimize
Nonzero if the drawing of the control is to be optimized, otherwise 0. If the drawing is optimized, the state of the device context is automatically restored when you are finished rendering.

bZoomed
Nonzero if the target has a zoom factor, otherwise 0. The zoom factor is stored in ZoomNum.

bRectInHimetric
Nonzero if the dimensions of prcBounds are in HIMETRIC, otherwise 0.

ZoomNum
The width and height of the rectangle into which the object is rendered. The zoom factor along the x-axis (the proportion of the object's natural size to its current extent) of the target is the value of ZoomNum.cx divided by the value of ZoomDen.cx. The zoom factor along the y-axis is achieved in a similar fashion.

ZoomDen
The actual width and height of the target.

Remarks

Typical usage of this structure would be the retrieval of information during the rendering of the target object. For example, you could retrieve values from ATL_DRAWINFO inside your overload of CComControlBase::OnDrawAdvanced.

This structure stores pertinent information used to render the appearance of an object for the target device. The information provided can be used in drawing to the screen, a printer, or even a metafile.

Requirements

Header: atlctl.h

See Also

Structures
IViewObject::Draw
CComControlBase::OnDrawAdvanced