THORLABS DCC1 45 Series, User Manual

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130 DCx camera
© 2010 Thorlabs
7.3.9
is_DirectRenderer
USB 2.0 -
Syntax
INT is_DirectRenderer (HIDS hCam, UINT nMode, void* pParam, UINT nSize)
Description
is_DirectRenderer()
provides a set of advanced rendering functions and allows inserting overlay
data into the camera's live image without flicker. The graphics card functions of the Direct3D library
are supported under Windows.
Notes on using the function:
The second input parameter
nMode
specifies the effect of the
is_DirectRenderer()
call.
The value of the third parameter
pParam
depends on the mode selected with
nMode
: For example,
when setting the overlay size (
nMode = DR_SET_OVERLAY_SIZE
), a pointer to an array of two values
(x and y) is passed (see code samples). When you load a bitmap image (
nMode =
DR_LOAD_OVERLAY_FROM_FILE
),
pParam
passes the path to the file (see code samples). The required
parameters are illustrated in the sample codes at the end of this section.
To use the Direct3D functionality, the appropriate version of the Microsoft DirectX Runtime has
to be installed in your PC.
When you are using high-resolution cameras, the maximum texture size supported by the
graphics card should be at least 4096 x 4096 pixels. You can check the maximum texture size
by reading out the D3D_GET_MAX_OVERLAY_SIZE parameter.
The Direct3D mode automatically uses the Windows Desktop color depth setting for the
display.
Please also read the notes on graphics cards which are provided in the System Requirements
chapter.
Input Parameters
hCam
Camera handle
nMode
DR_GET_OVERLAY_DC
Returns the device context (DC) handle to the overlay area of the graphics card.
In Direct3D mode, the DR_GET_OVERLAY_DC mode returns the device context (DC)
handle of the overlay area. Using this handle, it is possible to access the overlay using the
Windows GDI functionality. Thus, all Windows graphics commands (e.g. Line, Circle,
Rectangle, TextOut) are available. To transfer the drawn elements to the overlay, release the
DC handle by calling DR_RELEASE_OVERLAY_DC.
- Code sample
DR_RELEASE_OVERLAY_DC
Releases the device context (DC) handle.
Using DR_RELEASE_OVERLAY_DC, you can release the DC handle and update the overlay
data.
- Code sample
DR_GET_MAX_OVERLAY_SIZE
Returns the width
x
and height
y
of the maximum overlay area supported by the graphics card.
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