I need to save image of my DrawingArea object to Bitmap, but I can't find how to do it. Can anybody tell, how save DrawingArea image to Bitmap?
There are a few ways to do this, it depends exactly what you want to do and whether/why you really need a System.Drawing.Bitmap.
Copy the Widget
You can P/Invoke gtk_widget_get_snapshot to get a Gdk.Pixbuf.
The Pixbuf can be can be saved into a a file, or copied into a System.Drawing.Bitmap.
Using System.Drawing
You could port your drawing code to the System.Drawing API.
In your DrawingArea's Expose method, use Gtk.DotNet.Graphics.FromDrawable to get a System.Drawing.Graphics for your widget and draw onto that using your ported drawing code.
Then, you can create a System.Drawing.Bitmap and use the same drawing code to draw to it.
Using Cairo
You could port your drawing code to Mono.Cairo (the new GTK# drawing APIs, which are much more powerful than System.Drawing).
In your DrawingArea's Expose method, use Gdk.CairoHelper.Create to get a Cairo context for your widget and draw onto that using your ported drawing code.
Then, you can use your Cairo drawing logic to write to a Cairo ImageSurface, which can be saved into a a file, or copied into a System.Drawing.Bitmap.
Related
I have been searching around about this problem for awhile. I am making a cross platform program and I have figured out how to load an animated cursor with the windows API and how to create a cursor during run time from raw bitmap data. However I can't find good documentation for this for X11, for my Unix/Linux build of my program. I know I need to use the XRender extension functions, XRenderCreateCursor and XRenderCreateAnimCursor from this documentation https://www.x.org/releases/X11R7.6/doc/libXrender/libXrender.txt but I do not know how to use these functions and the documentation does now show any examples.
Also the raw image data is in the ARGB format, and I want to support the Alpha channel if possible with these cursors.
Could someone show me how to use the X11 and XRender (or XCursor) Library to create a cursor, static and animated, and possibly how to do it so the cursor can be used with any X11 window.
Thanks!
PS.
I am acually editing a open source libary for cross platfrom Gui that I am using for my program, and I am trying to add this feature into the libary but I am not used to programing with X11.
When it comes to X, nothing is simple.
First, review the specification of the X render extension.
The steps for creating an animated cursor are as follows.
First, you need to create a PICTURE for each frame of the animated cursor, using CreatePicture.
Use CreateCursor to create a CURSOR from each PICTURE. CreateCursor returns a CURSOR handle.
Then, you take the list of all CURSORs for all of the frames, and then use CreateAnimCursor to create a single CURSOR representing the animated cursor.
This all comes down to creating a PICTURE for each frame. A PICTURE is created using CreatePicture from a DRAWABLE and a PICTFORMAT. DRAWABLE would be the PIXMAP with the actual bitmask for the cursor's frame, and PICTFORMAT specifies which channels in the pixmap represent the red, color, and green channels, and must be one of the enumerated PICTFORMATs returned from QueryPictformat.
For more information, see the aforementioned X render extension specification.
I'm trying to create a bitmap that I can change the pixels of and then update the window with that bitmap. I've tried to research a way to just create a bitmap, but that was to no avail.
I need to know how to create a blank bitmap, then change its pixels using x and y coordinates and a color, and then how to draw it to the window. I don't need to save it to the computer and I don't want to convert an existing image into a bitmap.
I'm on windows and using Visual Studio with C++
Just to specify, I need to know the syntax for creating a blank bitmap with a certain width and height, and also what function I need to use to change the pixels' colors, and then how to draw a bitmap to the window. Thank you.
There is a free library ImgSource that you can use which has a huge amount of functionality for images.
http://www.smalleranimals.com/isource.htm
It is available in MSDN, but using a library like ImgSource may be to your advantage.
It provides simple methods for rendering your image onto a device context. And there is a good support forum.
Just like to add a bit question similar to this link. Is there anyway I could do to draw outside the client window using OpenGL without any native commands to be used? or is this beyond OpenGL previleges?
Other ways I could think of is to draw a sub window and remove the built in borders and button on it, then draw what I wanted there?
I want to draw some primitives (for example lines or text) on given window with gtkmm (gdkmm / gdk) with keeping old content of this window. I guess that using DrawingArea widget may be no helpful because I need draw on the old pixbuf.
Maybe I need to rearrange this pixbuf and load it again to this window? Is it possible?
Maybe I need to instert something between begin_paint_region() and end_paint()?
thanks.
I would like a win32 program that takes the desktop and acts like it is shattering glass and in the end would put the pieces back together is there way reference on Doing this kind of effect with C++?
I wrote a program (unfortunately now lost) to do something like this a few years ago.
The desktop image can be retrieved by creating a DC for the screen, creating a compatible bitmap, then using BitBlt to copy the screen contents into the bitmap. Then use GetDIBits to get the pixels from this bitmap in a known format.
This link doesn't do exactly that, but it demonstrates the principle, albeit using MFC. I couldn't find a Win32-specific example:
http://www.flounder.com/screencapture.htm
For the shattering effect, best to use Direct3D or OpenGL. (Further details are up to you.) Create a texture using the bitmap data saved earlier.
By way of window for associating with OpenGL or D3D, create a borderless window that fills the entire screen and doesn't do painting or background erasing. This will prevent any flicker when switching from the desktop image to the copy of the desktop image being used to draw.
(If using D3D, you'll also find GetMonitorInfo useful in conjunction with IDirect3D9::GetAdapterMonitor and friends, as you'll need to create a separate device for each monitor and you'll therefore need to know which portion of the desktop corresponds to that device.)