Returns block width.
arg1: Block handle
arg2: Current character
width
case VSM_WF_GET_WIDTH:
{
int x = (int)lParam;
return (LPSTR)(23 * x);
}
Returns block sizes packed as LOWORD (block width); HIWORD (block height).
arg1: Block handle
arg2: LOWORD: current
character width; HIWORD:current character height
case VSM_WF_GET_HEIGHT:
{
int y = HIWORD(lParam);
int x = LOWORD(lParam);
return (LPSTR)MAKELPARAM(23 * x, 6 * y);
}
Gets the block window style. The styles correspond to the description of the CWnd::CreateEx function.
arg1: &style
arg2: hDC
case VSM_WF_WINDOW_STYLES:
{
DWORD* flags = (DWORD*)wParam;
DWORD* exFlags = (DWORD*)lParam;
// *flags &= ~(WS_CAPTION);
return (LPSTR)true;
}
After getting the styles, Embed creates a block window using the CWnd::CreateEx function. Immediately after the block window is created, Embed invokes the Window function with arguments:
HWND: Block window handle
arg1: Block
handle
At this stage, the provided block window handle should be stored in the block-associated data structure. You can customize the block window—for example, change its title—or create child windows using the provided handle as a parent window handle.
case VSM_WF_CREATE_WINDOW:
{
HWND hParent = h;
Display_INFO* pi =
(Display_INFO*)vissimRequest(VR_GET_BLOCK_PARAMS,
wParam, 0);
pi->hwnd = h;
SetWindowText(pi->hwnd, "New Title");
return (LPSTR)true;
}
As shown above, the identifier Display_INFO defines the user block data structure.
Embed then tries to resize the block window due to Windows mechanics. In this case, Embed resends the VSM_WF_GET_WIDTH and VSM_WF_GET_HEIGHT requests again.
Once a block window is inserted in the diagram, the block plotting function from Embed uses the VSM_WF_RECTANGLE request to provide the exact window sizes to add-on module.
arg1: width
arg2: height
The parameters should be stored within the add-on module for a subsequent printing call, if it needed.
VSM_WF_RECTANGLE is also sent before printing.
case VSM_WF_RECTANGLE:
// This
message is sent right before
VSM_WF_PRINT_WINDOW, thus the values
stay correct
nWidthForPrinting = wParam;
nHeightForPrinting = lParam;
break;
Immediately after VSM_WF_RECTANGLE, Embed sends either:
•A pair of requests VSM_WF_PLOT_WINDOW and VSM_WF_SELECT_WINDOW
•VSM_WF_PRINT_WINDOW
The above requests have similar arguments:
HWND: parent’s handle
arg1: Block
handle
arg2: Device context for painting (hDC)
The add-on must paint the content of the windows as a response to the VSM_WF_PLOT_WINDOW request. If the block has been selected in Embed, it is highlighted by changing the block background color. However, if the block created by the add-on covers the entire area of block window, you must update the block window as a response to VSM_WF_SELECT_WINDOW.
case VSM_WF_PLOT_WINDOW:
{
Display_INFO* pi =
(Display_INFO*)vissimRequest(VR_GET_BLOCK_PARAMS,
wParam, 0);
HDC = (HDC)lParam;
<< some plotting using h, hdc, and pi >>
return (LPSTR)true;
}
During simulation, Embed sends two requests VSM_WF_RECTANGLE and VSM_WF_PLOT_WINDOW on each simulation step.
Before destroying the block window, Embed sends the VSM_WF_DESTROY_WINDOW request with arguments:
HWND: Block window handle
arg1: Block
handle
In response, the add-on must remove everything that uses the block window as a parent window. Also, the block widow handle within the add-on should be changed to NULL. The block window itself is destroyed by Embed.
case VSM_WF_DESTROY_WINDOW:
{
Display_INFO* pi =
(Display_INFO*)vissimRequest(VR_GET_BLOCK_PARAMS,
wParam, 0);
pi->hwnd = NULL;
return (LPSTR)true;
}
If you change settings that affect the entire diagram, such as the font or the current magnification, the add-on receives the VSM_WF_REORG request with arguments:
arg1: Block handle
arg2: LOWORD: current
character width; HIWORD:current character height