Open Inventor练习-传感器（SoFieldSensor）功能

传感器是Open Inventor的重要功能，也是其重要特性，有了它三维功能可以做的活灵活现，此例子是演示的一个圆锥体动作传感器（SoFieldSensor）监视，实际是关联到视镜的摄像头上，只要其位置发生变化，传感器就会感知到，并输出新的位置信息到控制台窗口。代码如下。

#define COIN_DLL  
#define SOWIN_DLL  
// 加载COIN库文件  
#ifdef _DEBUG  
#pragma comment(lib, "SoWin1d.lib")  
#pragma comment(lib, "Coin3d.lib")  
#else  
#pragma comment(lib, "SoWin1.lib")  
#pragma comment(lib, "Coin3.lib")  
#endif  
// 添加COIN头文件-Window操作显示库和节点库  
#include <Inventor/Win/SoWin.h>
#include <Inventor/Win/viewers/SoWinExaminerViewer.h>
#include <Inventor/events/SoKeyboardEvent.h>
#include <Inventor/nodes/SoCone.h>
#include <Inventor/nodes/SoDirectionalLight.h>
#include <Inventor/nodes/SoEventCallback.h>
#include <Inventor/nodes/SoMaterial.h>
#include <Inventor/nodes/SoPerspectiveCamera.h>
#include <Inventor/nodes/SoTransform.h>
#include <Inventor/nodes/SoSeparator.h>
#include <Inventor/nodes/SoSwitch.h>
#include <Inventor/sensors/SoFieldSensor.h>

void moveCB(void *data, SoSensor *sensor) 
{
	SoSFVec3f *pos = (SoSFVec3f *)((SoFieldSensor *)sensor)->getAttachedField();
	printf("detected camera movement: %f %f %f\n", 
		pos->getValue()[0], pos->getValue()[1], pos->getValue()[2]);
}

int main(int argc, char **argv) 
{
	HWND w = SoWin::init(argv[0]);
	SoWinExaminerViewer *viewer = new SoWinExaminerViewer(w);
	viewer->setSceneGraph(new SoCone);
	SoCamera *camera = viewer->getCamera();

	SoFieldSensor *sensor = new SoFieldSensor(moveCB, NULL);
	sensor->attach(&camera->position);

	SoWin::show(w);
	viewer->show();
	SoWin::mainLoop();
}

演示结果如下.