new_extern_window — Create a virtual graphics window under Windows.
new_extern_window opens a new virtual window. Note that this only works on Windows systems.
Virtual means that a new window will not be created, but the window whose window handle is given in the parameter WINHWnd is used to perform output of gray value data, regions, graphics as well as to perform textual output. Visualization parameters for the output of data can be done either using HALCON commands or by the appropriate Windows commands.
Example: setting of the drawing color:
HPEN penGreen = CreatePen(PS_SOLID,1,RGB(0,255,0));
pen = (HPEN*)SelectObject(WINHDC,penGreen);
All operators that allow the user to define graphical primitives through mouse interactions, like for example draw_rectangle1, do not work on external windows. The following operators can be used:
Image part: set_part
You may query current set values by calling operators like get_shape. As some parameters are specified through the hardware (Resolution/Colors), you may query current available resources by calling operators like query_color.
The parameter WINHWnd is used to pass the window handle of the window in which output should be done.
The origin of the coordinate system of the window resides in the upper left corner (coordinates: (0,0)). The row index grows downward (maximum: Height-1), the column index grows to the right (maximal: Width-1).
You may use the value -1 for parameters Width and Height. This means, that the corresponding value is chosen automatically. In particular, this is important if the aspect ratio of the pixels is not 1.0 (see set_system). If one of the two parameters is set to -1, it will be chosen through the size which results out of the aspect ratio of the pixels. If both parameters are set to -1, they will be set to the current image format.
The position and size of a window may change during runtime of a program, e.g., through external influences (window manager). With the operator set_window_extents, you can change the size of the (external) widow via the program. Note that set_window_extents offers to change the position as well, but you cannot change the position of an external window under Windows.
Opening a window causes the assignment of a default font. It is used in connection with operators like write_string and you may change it by performing set_font after calling open_window. On the other hand, you have the possibility to specify a default font by calling set_system(::'default_font',<Fontname>:) before opening a window (and all following windows; see also query_font).
You may set the color of graphics and font, which is used for output operators like disp_region or disp_circle, by calling set_rgb, set_hsi, set_gray or set_pixel. Calling set_insert specifies how graphics is combined with the content of the image repeat memory. Thereto you may achieve by calling, e.g., set_insert(::'not':) to eliminate the font after writing text twice at the same position.
The content of the window is not saved, if other windows overlap the window. This must be done in the program code that handles the window in the calling program.
For graphical output (disp_image,disp_region, etc.) you may adjust the window by calling the operator set_part in order to represent a logical clipping of the image format. In particular this implies that only this part (appropriately scaled) of images and regions is displayed. Before you close your window, you have to close the HALCON-window.
Steps to use new_extern_window:
Create a Windows-window.
Call new_extern_window with the WINHWnd of the above created window.
Before drawing in the window you have to call the method set_window_dc. This ensures that the HALCON drawing routines use the right DC. After drawing call again set_window_dc, but this time with the address of a long set to zero, this ensures that HALCON can delete the created graphic objects.
Note that parameters as Row, Column, Width and Height are constrained through the output device, i.e., the size of the Windows NT desktop. Furthermore, be aware that all operators that allow the user to define graphical primitives through mouse interactions, like for example draw_rectangle1, do not work on external windows.
This operator returns a handle. Note that the state of an instance of this handle type may be changed by specific operators even though the handle is used as an input parameter by those operators.
Windows window handle of a previously created window.
Restriction: WINHWnd != 0
Row coordinate of upper left corner.
Default value: 0
Restriction: Row >= 0
Column coordinate of upper left corner.
Default value: 0
Restriction: Column >= 0
Width of the window.
Default value: 512
Restriction: Width > 0 || Width == -1
Height of the window.
Default value: 512
Restriction: Height > 0 || Height == -1
// Needs to be embedded into an application framework, // see examples/cpp/mfc/MatchingExtWin.
If the values of the specified parameters are correct new_extern_window returns 2 (H_MSG_TRUE). If necessary, an exception is raised.
set_color, query_window_type, get_window_type, set_window_type, get_mposition, set_tposition, set_tshape, set_window_extents, get_window_extents, query_color, set_check, set_system
open_window, disp_region, disp_image, disp_color, set_lut, query_color, set_color, set_rgb, set_hsi, set_pixel, set_gray, set_part, set_part_style, query_window_type, get_window_type, set_window_type, get_mposition, set_tposition, set_window_extents, get_window_extents, set_window_attr, set_check, set_system