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| GetDeviceCaps The GetDeviceCaps function retrieves device-specific information about a specified device. VB4-32,5,6
Declare Function GetDeviceCaps Lib "gdi32" Alias "GetDeviceCaps" (ByVal hdc As Long, ByVal nIndex As Long) As Long |
| Operating Systems Supported |
| Requires Windows NT 3.1 or later; Requires Windows 95 or later |
· hdc
Identifies the device context.
· nIndex
Specifies the item to return. This parameter can be one of the following values:
DRIVERVERSION
The device driver version.
TECHNOLOGY
Device technology. It can be any one of the following values:
DT_PLOTTER
Vector plotter
DT_RASDISPLAY
Raster display
DT_RASPRINTER
Raster printer
DT_RASCAMERA
Raster camera
DT_CHARSTREAM
Character stream
DT_METAFILE
Metafile
DT_DISPFILE
Display file
If the hdc parameter identifies the device context of an enhanced metafile, the device technology is that of the referenced device as given to the CreateEnhMetaFile function. To determine whether it is an enhanced metafile device context, use the GetObjectType function.
HORZSIZE
Width, in millimeters, of the physical screen.
VERTSIZE
Height, in millimeters, of the physical screen.
HORZRES
Width, in pixels, of the screen.
VERTRES
Height, in raster lines, of the screen.
LOGPIXELSX
Number of pixels per logical inch along the screen width.
LOGPIXELSY
Number of pixels per logical inch along the screen height.
BITSPIXEL
Number of adjacent color bits for each pixel.
PLANES
Number of color planes.
NUMBRUSHES
Number of device-specific brushes.
NUMPENS
Number of device-specific pens.
NUMFONTS
Number of device-specific fonts.
NUMCOLORS
Number of entries in the device’s color table, if the device has a color depth of no more than 8 bits per pixel. For devices with greater color depths, -1 is returned.
ASPECTX
Relative width of a device pixel used for line drawing.
ASPECTY
Relative height of a device pixel used for line drawing.
ASPECTXY
Diagonal width of the device pixel used for line drawing.
PDEVICESIZE
Reserved.
CLIPCAPS
Flag that indicates the clipping capabilities of the device. If the device can clip to a rectangle, it is 1. Otherwise, it is 0.
SIZEPALETTE
Number of entries in the system palette. This index is valid only if the device driver sets the RC_PALETTE bit in the RASTERCAPS index and is available only if the driver is compatible with Windows version 3.0 or later.
NUMRESERVED
Number of reserved entries in the system palette. This index is valid only if the device driver sets the RC_PALETTE bit in the RASTERCAPS index and is available only if the driver is compatible with Windows version 3.0 or later.
COLORRES
Actual color resolution of the device, in bits per pixel. This index is valid only if the device driver sets the RC_PALETTE bit in the RASTERCAPS index and is available only if the driver is compatible with Windows version 3.0 or later.
PHYSICALWIDTH
For printing devices: the width of the physical page, in device units. For example, a printer set to print at 600 dpi on 8.5"x11" paper has a physical width value of 5100 device units. Note that the physical page is almost always greater than the printable area of the page, and never smaller.
PHYSICALHEIGHT
For printing devices: the height of the physical page, in device units. For example, a printer set to print at 600 dpi on 8.5"x11" paper has a physical height value of 6600 device units. Note that the physical page is almost always greater than the printable area of the page, and never smaller.
PHYSICALOFFSETX
For printing devices: the distance from the left edge of the physical page to the left edge of the printable area, in device units. For example, a printer set to print at 600 dpi on 8.5"x11" paper, that cannot print on the leftmost 0.25" of paper, has a horizontal physical offset of 150 device units.
PHYSICALOFFSETY
For printing devices: the distance from the top edge of the physical page to the top edge of the printable area, in device units. For example, a printer set to print at 600 dpi on 8.5"x11" paper, that cannot print on the topmost 0.5" of paper, has a vertical physical offset of 300 device units.
VREFRESH
Windows NT only: For display devices: the current vertical refresh rate of the device, in cycles per second (Hz).
A vertical refresh rate value of 0 or 1 represents the display hardware’s default refresh rate. This default rate is typically set by switches on a display card or computer motherboard, or by a configuration program that does not use Win32 display functions such as ChangeDisplaySettings.
DESKTOPHORZRES
Windows NT only: Width, in pixels, of the virtual desktop. This value may be larger than HORZRES if the device supports a virtual desktop or multiple displays.
DESKTOPVERTRES
Windows NT only: Height, in pixels, of the virtual desktop. This value may be larger than VERTRES if the device supports a virtual desktop or multiple displays.
BLTALIGNMENT
Windows NT only: Preferred horizontal drawing alignment, expressed as a multiple of pixels. For best drawing performance, windows should be horizontally aligned to a multiple of this value. A value of zero indicates that the device is accelerated, and any alignment may be used.
RASTERCAPS
Value that indicates the raster capabilities of the device, as shown in the following table:
RC_BANDING
Requires banding support.
RC_BITBLT
Capable of transferring bitmaps.
RC_BITMAP64
Capable of supporting bitmaps larger than 64K.
RC_DI_BITMAP
Capable of supporting the SetDIBits and GetDIBits functions.
RC_DIBTODEV
Capable of supporting the SetDIBitsToDevice function.
RC_FLOODFILL
Capable of performing flood fills.
RC_GDI20_OUTPUT
Capable of supporting features of Windows 2.0.
RC_PALETTE
Specifies a palette-based device.
RC_SCALING
Capable of scaling.
RC_STRETCHBLT
Capable of performing the StretchBlt function.
RC_STRETCHDIB
Capable of performing the StretchDIBits function.
CURVECAPS
Value that indicates the curve capabilities of the device, as shown in the following table:
CC_NONE
Device does not support curves.
CC_CIRCLES
Device can draw circles.
CC_PIE
Device can draw pie wedges.
CC_CHORD
Device can draw chord arcs.
CC_ELLIPSES
Device can draw ellipses.
CC_WIDE
Device can draw wide borders.
CC_STYLED
Device can draw styled borders.
CC_WIDESTYLED
Device can draw borders that are wide and styled.
CC_INTERIORS
Device can draw interiors.
CC_ROUNDRECT
Device can draw rounded rectangles.
LINECAPS
Value that indicates the line capabilities of the device, as shown in the following table:
LC_NONE
Device does not support lines.
LC_POLYLINE
Device can draw a polyline.
LC_MARKER
Device can draw a marker.
LC_POLYMARKER
Device can draw multiple markers.
LC_WIDE
Device can draw wide lines.
LC_STYLED
Device can draw styled lines.
LC_WIDESTYLED
Device can draw lines that are wide and styled.
LC_INTERIORS
Device can draw interiors.
POLYGONALCAPS
Value that indicates the polygon capabilities of the device, as shown in the following table:
PC_NONE
Device does not support polygons.
PC_POLYGON
Device can draw alternate-fill polygons.
PC_RECTANGLE
Device can draw rectangles.
PC_WINDPOLYGON
Device can draw winding-fill polygons.
PC_SCANLINE
Device can draw a single scanline.
PC_WIDE
Device can draw wide borders.
PC_STYLED
Device can draw styled borders.
PC_WIDESTYLED
Device can draw borders that are wide and styled.
PC_INTERIORS
Device can draw interiors.
TEXTCAPS
Value that indicates the text capabilities of the device, as shown in the following table:
TC_OP_CHARACTER
Device is capable of character output precision.
TC_OP_STROKE
Device is capable of stroke output precision.
TC_CP_STROKE
Device is capable of stroke clip precision.
TC_CR_90
Device is capable of 90-degree character rotation.
TC_CR_ANY
Device is capable of any character rotation.
TC_SF_X_YINDEP
Device can scale independently in the x- and y-directions.
TC_SA_DOUBLE
Device is capable of doubled character for scaling.
TC_SA_INTEGER
Device uses integer multiples only for character scaling.
TC_SA_CONTIN
Device uses any multiples for exact character scaling.
TC_EA_DOUBLE
Device can draw double-weight characters.
TC_IA_ABLE
Device can italicize.
TC_UA_ABLE
Device can underline.
TC_SO_ABLE
Device can draw strikeouts.
TC_RA_ABLE
Device can draw raster fonts.
TC_VA_ABLE
Device can draw vector fonts.
TC_RESERVED
Reserved; must be zero.
TC_SCROLLBLT
Device cannot scroll using a bit-block transfer. Note that this meaning may be the opposite of what you expect. |
| The return value specifies the value of the desired item. |
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