On Thu, 25 Jan 2007 09:44:59 -0700, alexander Serechenko Alexander
<[EMAIL PROTECTED]> wrote:
Is there any way to copy some transparent image over another?
Only way I found is to use AlphaCopyToDC to some virtual DC, but i
can't find any way to get Win32::GUI::DC not associated with any
device.
Is any one can help me?
Win32::GUI::DC::CreateCompatibleDC()
Creates a memory device context (DC) compatible with the specified device.
That's all the documentation there is. According to the source (DC.xs), it
returns a Win32::GUI::DC object, not just a handle. Of course, if it is
just a handle, it's easy enough to do:
my $dc = bless {
-handle => Win32::GUI::CreateCompatibleDC(),
}, 'Win32::GUI::DC';
And according to Microsoft, calling it with no handle should give you a DC
compatible with the current screen. Here's an excerpt:
The CreateCompatibleDC function creates a memory device context (DC)
compatible with the specified device.
HDC CreateCompatibleDC(
HDC hdc // handle to DC
);
Parameters
hdc
[in] Handle to an existing DC. If this handle is NULL, the function
creates a memory DC compatible with the application's current screen.
Return Values
If the function succeeds, the return value is the handle to a memory DC.
If the function fails, the return value is NULL.
Remarks
A memory DC exists only in memory. When the memory DC is created, its
display surface is exactly one monochrome pixel wide and one monochrome
pixel high. Before an application can use a memory DC for drawing
operations, it must select a bitmap of the correct width and height into
the DC. To select a bitmap into a DC, use the CreateCompatibleBitmap
function, specifying the height, width, and color organization required.
When a memory DC is created, all attributes are set to normal default
values. The memory DC can be used as a normal DC. You can set the
attributes; obtain the current settings of its attributes; and select
pens, brushes, and regions.
