How to accept MathML?

Question

I discovered today that Windows 7 comes with a very impressive MathPanel utility for performing handwriting recognition:

This is normal. (Here I introduced the formula for the gamma conversion part of the sRGB color space)

But now I seem to be unable to do anything about it.

There is an Insert button. I would suggest that clicking Paste will paste it into the active application behind it (just like the on-screen keyboard works):

In addition, I assume that it will work as an Insert operation.

I can not find any information in the help system about what the application requires for its operation. There is no mention of any special APIs that some programs must support.

Also I can not find any information about MSDN about what special API is required to accept the insertion of the equation.

What API, registration, callback, listener, message, COM object do I need to implement so that I get the MathPanel input?

The only reason I mention MathML is the answer to SuperUser mentioned by MathML :

Theoretically, any application that supports MathML (a mathematical markup language) can be used with the Math Windows 7 input panel. The Math input panel only works with programs that support MathML. Here are a few of these applications: StarOffice, OpenOffice, Opera, and Maple.

Well, how do I make support for my MathML program?

As far as I know, MathML is a markup language; not the Windows API. It would be like saying: "How do I make HTML support for my program?" Html is text and you can paste it anywhere.

MathPad refuses to embed if I do not support MathML?

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Update

Checking IDataObject in the clipboard after clicking Paste , I see two available formats (none of them are text, which explains why I am not getting markup):

Format 1:

  CLIPFORMAT cfFormat: "MathML Presentation" (49839) PDVTargetDevice ptd: 0x00000000 DWORD dwAspect: DVASPECT_CONTENT DWORD lindex: -1 DWORD tymed: 1 (TYMED_HGLOBAL) 

Format 2:

  CLIPFORMAT cfFormat:"MathML" (49838) PDVTargetDevice ptd: 0x00000000 DWORD dwAspect: DVASPECT_CONTENT DWORD lindex: -1 DWORD tymed: 1 (TYMED_HGLOBAL) 

So, at least now I have some clipboard formats:

• "MathML Presentation"
• "MathML"

I still cannot find anything on MSDN about any clipboard format.

Answer 1

Tracking messages sent to my window looks like this: the Math Input Panel application sends Ctrl+V :

• WM_KEYDOWN (0x11) VK_CONTROL
• WM_KEYDOWN Button (0x56) V
• WM_CHAR (0x16)
• WM_KEYUP (0x11) VK_CONTROL
• WM_KEYUP (0x56) V key

So, you need to admit that someone is trying to press Ctrl + V. Then you have to extract the contents.

First register three clipboard formats:

 Handle CF_MathML_Presentation = RegisterClipboardFormat("MathML Presentation"); Handle CF_MathML_Content = RegisterClipboardFormat("MathML Content"); Handle CF_MathML = RegisterClipboardFormat("MathML"); 

Note: Appendix B of the W3C Markup Language (MathML) version 3.0 documents the names of the Windows clipboard format for registration:

• Generic MathML Windows Clipboard Name: MathML
• MathML Presentation Windows Clipboard Name: MathML Presentation
• MathML Content Windows Clipboard Name: MathML Content

Then take the IDataObject handle on the clipboard:

 IDataObject dataObject; OleGetClipboard(dataObject); 

Then list all the formats, looking for the one you like:

 IEnumFORMATETC enum; dataObject.EnumFormatEtc(DATADIR_GET, out enum); String mathXml = ""; foreach (FormatEtc format in enum) { if (format.cfFormat = CF_MathML_Presentation) || (format.cfFormat = CF_MathML_Content) || (format.cfFormat = CF_MathML) { //We know how to handle these formats: STGMEDIUM medium; dataObject.GetData(format.cfFormat, out medium); mathXml = GetStringFromStorageMedium(medium); //handles all the nasty HGlobal/IStream/IStorage nonsense } } ShowMessage(mathXml); //tada! 

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Microsoft also lets you program the Math Input COM object :

 //Create the COM object IMathInputControl mathInputControl = CreateComObject(CLSID_MathInputControl); mathInputControl.Show(); 

Then you can create an object that receives notifications:

 class MathEvents : _IMathInputControlEvents { public HRESULT Insert(String mathXml) { //Notifies the event handler when the Insert button is clicked. MessageBox.Show(mathXml); return S_OK; } public HRESULT Clear() { //Notifies the event handler when the Clear button is clicked. return S_OK; } public HRESULT Close() { //Notifies the event handler when the Close button is clicked. return S_OK; } public HRESULT PaintHRESULT Paint(LONG_PTR hdc, LONG Left, LONG Top, LONG Right, LONG Bottom, LONG Element, LONG State) { //Notifies the event handler when the buttons and background of the control require painting. return S_OK; } 

An invalid ingredient is to give mathInputControl link to our callback object.

This top-secret complex COM code, including ConnectionPointContainer, and Advise`, which cannot be executed with C #.

But you do not need it, you can just use Ctrl+V

Answer 2

I think this is officially called the “Math Input Panel” (MIP Input Panel) (MIP). The MathType product supports it and provides a menu item to launch it. As the other answers mention, pressing the MIP Insert button sends Ctrl-V to the window below it. If this window supports this key combination and processes MathML, then it will work.

Although the MathML Clipboard format is the recommended way to handle MathML input in paste, if you use MathML support in your application, you should also accept the MathML text offered as CF_UNICODETEXT. Some applications support copying MathML to the clipboard, but do not seem to be aware of the MathML Clipboard format. Of course, your embed code will need to sniff the text to identify MathML, not plain text without MathML. You should also consider accepting drag and drop as well as paste.

Math Input Control is a related but slightly different MIP configuration. If I remember correctly, he lacks history and some other MIP features. We started working with him for MathType and quickly realized that there were no benefits. You should simply ignore it and just support the paste and drag and drop of MathML. Add a menu item to the Math Input Panel, if that makes sense for your application.

Answer 3

The "MathML Presentation" clipboard format actually contains text; I tried this before using the Windows API GetClipboardData ().

In addition, if you copy the MathML fragment to the clipboard as plain text (e.g. CF_TEXT), and then paste it into a Word document, you will also get plain text, i.e. Word does NOT interpret it as Presentation MathML.

For Word to do this, you must copy it as CF_TEXT, as well as "MathML Presentation". To get the ID of the latter, try registering "MathML Presentation" in the clipboard format proposed by Ian Boyd. Windows will return the clipboard format identifier; use this identifier with SetClipboardData ().