Window10手写笔压感数据获取

win10中获取手写笔压感数据使用GetPointerPenInfo函数，该函数在win7中不支持。
注：代码来源于互联网
使用方法：
1、在消息循环中增加处理 WM_POINTERUPDATE 消息

LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    switch (message)
    {
   ...
    case WM_POINTERUPDATE:
        if(!OnPointer(hWnd, message, wParam, lParam))
        	return DefWindowProc(hWnd, message, wParam, lParam);
    default:
        return DefWindowProc(hWnd, message, wParam, lParam);
    }
    return 0;
}

2、在OnPointer方法中处理该消息

LRESULT OnPointer(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
	UINT32       pointerId = GET_POINTERID_WPARAM(wParam);
	POINTER_INPUT_TYPE pointerType = PT_POINTER;

	// default to unhandled to enable call to DefWindowProc
	if (!GetPointerType(pointerId, &pointerType))	//获取消息类型
	{
		// failure, call GetLastError()
		// set PT_POINTER to fall to default case below
		pointerType = PT_POINTER;
	}
	if (pointerType == PT_PEN)				//手写笔的消息
	{
		POINTER_PEN_INFO penInfo;
		if (GetPointerPenInfo(pointerId, &penInfo))
		{
			Draw(penInfo.pointerInfo.ptPixelLocation.x,		//X坐标
			penInfo.pointerInfo.ptPixelLocation.y,			//Y坐标
			penInfo.pressure);								//压力值0~1024
		}
		return TRUE;
	}
	else if (pointerType == PT_TOUCH)				//触摸的消息
	{
		POINTER_TOUCH_INFO touchInfo;
		if (GetPointerTouchInfo(pointerId, &touchInfo))
		{
			Draw(touchInfo.pointerInfo.ptPixelLocation.x,		//X坐标
			touchInfo.pointerInfo.ptPixelLocation.y,			//Y坐标
			touchInfo.pressure);								//压力值（512固定）
		}
		return TRUE;
	}
	//其他的消息返回FALSE，交给windows的默认处理函数
	return FALSE;
}