直接使用变量（数组返回在数组中相同）还是用指针？ [英] Use a variable directly(data return are same in an array) or with pointer?
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问题描述
我有两只鸟传感器，我参考手册中的示例代码＃8，c ++代码正在为我工作。
I had two flock of bird sensor and i have refer to example code #8 in manual, the c++ code is working for me.
但我只得到一个传感器数据从c项目。问题是在C＃示例中，bird_data [1]和bird_data [2]似乎具有相同的位置数据。在C ++示例中，bird_data [1]和bird_data [2]都有正确的数据。我从下面的代码中获取相同的位置输出数据。
But i only get one sensor data from the c sharp project. The problem is that in the C# example, bird_data[1] and bird_data[2] appear to have same position data. In the C++ example both bird_data[1] and bird_data[2] have correct data.I get the same position output data from below code.
LBird1X中的文本输出是相同的LBird2X，LBird1Y是相同的LBird2Y和LBird1Z是相同的LBird2Z。
text output in the LBird1X is same LBird2X,LBird1Y is same LBird2Y and LBird1Z is same LBird2Z.
这可能是与缺乏指向？或者我在导入bird.dll结构数据时做错了什么？
Could this be to do with the lack of pointing ? Or i done something wrong in import the bird.dll stucture data?
C ++代码：
birdStartFrameStream(GROUP_ID);
do // Until Keypress
{
if(birdFrameReady(GROUP_ID)) // Check if there's data available
{
birdGetMostRecentFrame(GROUP_ID,&frame);//Get data from bird BIRDREADING *bird_data; // Transfers data into structure
BIRDREADING *bird_data;
for(int i=1; i<DEVCOUNT+1; i++ ) // Loop to get data from birds
{
// Change pointer to index of first bird (1)
bird_data = &frame.reading[i]; // Convert data into inches and degrees and scale
pos[0] = bird_data->position.nX * 36 / 32767.;
pos[1] = bird_data->position.nY * 36 / 32767.;
pos[2] = bird_data->position.nZ * 36 / 32767.;
ang[0] = bird_data->angles.nAzimuth * 180. / 32767.;
ang[1] = bird_data->angles.nElevation * 180. / 32767.;
ang[2] = bird_data->angles.nRoll * 180. / 32767.;
// print data
printf("%i> %+6.1f %+6.1f %+6.1f ", i,pos[0], pos[1],pos[2]);
// printf("%+6.1f %+6.1f %+6.1f \n",ang[0], ang[1], ang[2]);
} // end move data from structure to screen loop
} // end if frame ready loop
} while(!kbhit()); // loop until any key is pressed
if (birdFrameReady(GROUP_ID))
{
birdGetMostRecentFrame(GROUP_ID, ref frame);
BIRDREADING bird_data = new BIRDREADING();
bird_data = frame.readings[i];
for (i = 1; i < DEVCOUNT + 1; i++)
{
bird_data = frame.readings[i];
string x, y, z;
x = (bird_data.position.nX * 36 / 32767.0).ToString();
y = (bird_data.position.nY * 36 / 32767.0).ToString();
z = (bird_data.position.nZ * 36 / 32767.0).ToString();
switch (i)
{
case 1:
LBird1X.Text = i.ToString() + ": " + x;
LBird1Y.Text = i.ToString() + ": " + y;
LBird1Z.Text = i.ToString() + ": " + z;
break;
case 2:
LBird2X.Text = i.ToString() + ": " + x;
LBird2Y.Text = i.ToString() + ": " + y;
LBird2Z.Text = i.ToString() + ": " + z;
break;
default:
LBird2X.Text = "error";
LBird2Y.Text = "error";
LBird2Z.Text = "error";
break;
}
}
strong>
C++ Struct
#pragma pack(1) // pack the following structures on one-byte boundaries
// Bird position structure
typedef struct tagBIRDPOSITION
{
short nX; // x-coordinate
short nY; // y-coordinate
short nZ; // z-coordinate
}
BIRDPOSITION;
// Bird angles structure
typedef struct tagBIRDANGLES
{
short nAzimuth; // azimuth angle
short nElevation; // elevation angle
short nRoll; // roll angle
}
BIRDANGLES;
// Bird matrix structure
typedef struct tagBIRDMATRIX
{
short n[3][3]; // array of matrix elements
}
BIRDMATRIX;
// Bird quaternion structure
typedef struct tagBIRDQUATERNION
{
short nQ0; // q0
short nQ1; // q1
short nQ2; // q2
short nQ3; // q3
}
BIRDQUATERNION;
#pragma pack() // resume normal packing of structures
// Bird reading structure
typedef struct tagBIRDREADING
{
BIRDPOSITION position; // position of receiver
BIRDANGLES angles; // orientation of receiver, as angles
BIRDMATRIX matrix; // orientation of receiver, as matrix
BIRDQUATERNION quaternion; // orientation of receiver, as quaternion
WORD wButtons; // button states
}
BIRDREADING;
// Bird frame structure
//
// NOTE: In stand-alone mode, the bird reading is stored in reading[0], and
// all other array elements are unused. In master/slave mode, the "reading"
// array is indexed by bird number - for example, bird #1 is at reading[1],
// bird #2 is at reading[2], etc., and reading[0] is unused.
typedef struct tagBIRDFRAME
{
DWORD dwTime; // time at which readings were taken, in msecs
BIRDREADING reading[BIRD_MAX_DEVICE_NUM + 1]; // reading from each bird
}
BIRDFRAME;
// Bird system configuration structure
//
// NOTE: In TCP/IP mode, the following fields are NOT used:
// byXtalSpeed
//
// NOTE: In RS232 and ISA modes, the following fields are NOT used:
// bits BSS_FBB_ERROR, BSS_LOCAL_ERROR, BSS_LOCAL_POWER, and BSS_MASTER of bySystemStatus
// byNumServers
// byChassisNum
// byNumChassisDevices
// byFirstDeviceNum
strong> C sharp Stuct
C sharp Stuct
[StructLayout(LayoutKind.Sequential, Pack = 1)]
public struct BIRDPOSITION
{
public short nX; // x-coordinate
public short nY; // y-coordinate
public short nZ; // z-coordinate
}
// Bird angles structure
[StructLayout(LayoutKind.Sequential, Pack = 1)]
public struct BIRDANGLES
{
public short nAzimuth; // azimuth angle
public short nElevation; // elevation angle
public short nRoll; // roll angle
}
[StructLayout(LayoutKind.Sequential, Pack = 1)]
public struct BIRDMATRIX
{
[MarshalAs(UnmanagedType.ByValArray, SizeConst = 9)]
public short[,] n;
}
[StructLayout(LayoutKind.Sequential, Pack = 1)]
public struct BIRDQUATERNION
{
public short nQ0; // q0
public short nQ1; // q1
public short nQ2; // q2
public short nQ3; // q3
}
[StructLayout(LayoutKind.Sequential, Pack = 0)]
public struct BIRDREADING
{
public BIRDPOSITION position; // position of receiver
public BIRDANGLES angles; // orientation of receiver, as angles
public BIRDMATRIX matrix; // orientation of receiver, as matrix
public BIRDQUATERNION quaternion; // orientation of receiver, as quaternion
public ushort wButtons; // button states
}
[StructLayout(LayoutKind.Sequential, Pack = 0)]
public struct BIRDFRAME
{
public uint dwTime; // time at which readings were taken, in msecs
[MarshalAs(UnmanagedType.ByValArray, SizeConst = 127)]
public BIRDREADING[] readings; // reading from each bird
}
推荐答案
尝试使用 StructLayout（LayoutKind.Explicit）
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