OSG 自定义场景漫游示例

Posted 2020-07-27

 

一下代码可以简单实现osg中视角的简单自由漫游.并且可以进行简单的碰撞检测

 

 

mian.cpp

 1 #include <osgViewer/Viewer>
 2 
 3 #include <osg/Node>
 4 #include <osg/Geode>
 5 #include <osg/Group>
 6 
 7 #include <osgDB/ReadFile>
 8 #include <osgDB/WriteFile>
 9 
10 #include <osgUtil/Optimizer>
11 
12 #include "ManipulatorTravel.h"
13 
14 int main()
15 {
16 //创建Viewer对象，场景浏览器
17 osgViewer::Viewer* viewer = new osgViewer::Viewer();
18 
19 //把漫游器加入到场景中
20 TravelManipulator::TravelToScene(viewer);
21 
22 osg::Group* root = new osg::Group();
23 
24 //读取地形模型
25 osg::Node* node = new osg::Node();
26 node = osgDB::readNodeFile("lz.osg");
27 
28 //添加到场景
29 root->addChild(node);
30 
31 //优化场景数据
32 osgUtil::Optimizer optimizer ;
33 optimizer.optimize(root) ;
34 
35 viewer->setSceneData(root);
36 
37 viewer->realize();
38 
39 viewer->run();
40 
41 return 0 ;
42 }

 

 

ManipulatorTravel.h

#pragma once

#include <osgViewer/Viewer>

#include <osg/LineSegment>
#include <osg/Point>
#include <osg/Geometry>
#include <osg/Node>
#include <osg/Geode>
#include <osg/Group>

//#include <osgGA/MatrixManipulator>

#include <osgUtil/IntersectVisitor>

#include <vector>

class TravelManipulator :
public osgGA::CameraManipulator
{
public:

//构造函数
TravelManipulator ();

//析构函数
~TravelManipulator(void);

// 把漫游加入到场景之中
static TravelManipulator * TravelToScene(osg::ref_ptr <osgViewer::Viewer> viewer);

private:
osg::ref_ptr <osgViewer::Viewer>    m_pHostViewer;

//移动速度
float m_fMoveSpeed;
//
osg::Vec3 m_vPosition;
//
osg::Vec3 m_vRotation;

public:

//鼠标左键是否按下
bool m_bLeftButtonDown ;

//鼠标X,Y
float m_fpushY;

float m_fpushX;

//设置矩阵
virtual void setByMatrix(const osg::Matrixd& matrix);
//设置逆矩阵
virtual void setByInverseMatrix(const osg::Matrixd& matrix);
//得到矩阵
virtual osg::Matrixd getMatrix(void) const;
//得到逆矩阵
virtual osg::Matrixd getInverseMatrix(void)const ;

//事件处理函数
virtual bool handle(const osgGA::GUIEventAdapter& ea, osgGA::GUIActionAdapter& us);

// 屏目角度
float m_fAngle;

// 位置变换函数
void ChangePosition(osg::Vec3& delta);

//碰撞检测是否开启
bool m_bPeng;

//设置速度
float getSpeed() ;

void setSpeed(float &) ;

//设置起始位置
void SetPosition(osg::Vec3 &position) ;

osg::Vec3 GetPosition() ;

} ;

 

 

ManipulatorTravel.cpp

 

#include "ManipulatorTravel.h"

//构造函数
TravelManipulator::TravelManipulator(): m_fMoveSpeed(1.0f)
, m_bLeftButtonDown(false)
, m_fpushX(0)
, m_fAngle(2.5)
, m_bPeng(true)
, m_fpushY(0)
{
m_vPosition = osg::Vec3(-22.0f, -274.0f, 100.0f);

m_vRotation = osg::Vec3(osg::PI_2, 0.0f, 0.0f);

}
//析构函数
TravelManipulator::~TravelManipulator()
{
//
}
// 把漫游加入到场景之中
TravelManipulator * TravelManipulator::TravelToScene(osg::ref_ptr <osgViewer::Viewer> viewer)
{
TravelManipulator* camera = new TravelManipulator;

viewer->setCameraManipulator(camera) ;

camera->m_pHostViewer =viewer ;

return camera;    
}

// 设置矩阵
void TravelManipulator::setByMatrix(const osg::Matrixd& matrix)
{
//
}
//设置逆矩阵
void TravelManipulator::setByInverseMatrix(const osg::Matrixd& matrix)
{
//
}
//得到矩阵
osg::Matrixd TravelManipulator::getMatrix(void) const
{
osg::Matrixd mat;

mat.makeRotate(m_vRotation._v[0], osg::Vec3(1.0f, 0.0f, 0.0f),

m_vRotation._v[1], osg::Vec3(0.0f, 1.0f, 0.0f),

m_vRotation._v[2], osg::Vec3(0.0f, 0.0f, 1.0f));

return mat * osg::Matrixd::translate(m_vPosition);
}
//得到逆矩阵
osg::Matrixd TravelManipulator::getInverseMatrix(void) const 
{
osg::Matrixd mat;

mat.makeRotate(m_vRotation._v[0], osg::Vec3(1.0f, 0.0f, 0.0f),

m_vRotation._v[1], osg::Vec3(0.0f, 1.0f, 0.0f),

m_vRotation._v[2], osg::Vec3(0.0f, 0.0f, 1.0f));

return osg::Matrixd::inverse(mat * osg::Matrixd::translate(m_vPosition));
}
//事件处理函数
bool TravelManipulator::handle(const osgGA::GUIEventAdapter& ea, osgGA::GUIActionAdapter& us)
{
//得到鼠标的位置
float mouseX = ea.getX();
float mouseY = ea.getY();

switch(ea.getEventType())
{
case(osgGA::GUIEventAdapter::KEYDOWN):
{
//空格键
if (ea.getKey() == 0x20)
{
us.requestRedraw();

us.requestContinuousUpdate(false);

return true;
}
//上移动
if (ea.getKey() == 0xFF50)
{
ChangePosition(osg::Vec3 (0, 0, m_fMoveSpeed)) ;

return true;
}
//下移动 
if (ea.getKey() == 0xFF57)
{
ChangePosition(osg::Vec3 (0, 0, -m_fMoveSpeed)) ;

return true;
}
//增加速度
if (ea.getKey() == 0x2B)
{
m_fMoveSpeed += 1.0f;

return true;
}
//减少速度
if (ea.getKey() == 0x2D)
{
m_fMoveSpeed -= 1.0f;

if (m_fMoveSpeed < 1.0f)
{
m_fMoveSpeed = 1.0f;
}
return true;
}
//前进
if (ea.getKey() == 0xFF52 || ea.getKey () == 0x57 || ea.getKey () == 0x77)//up
{

ChangePosition(osg::Vec3 (0, m_fMoveSpeed * sinf(osg::PI_2+m_vRotation._v[2]), 0)) ;

ChangePosition(osg::Vec3 (m_fMoveSpeed * cosf(osg::PI_2+m_vRotation._v[2]), 0, 0)) ;

return true;
}
//后退
if (ea.getKey() == 0xFF54 || ea.getKey () == 0x53 || ea.getKey () == 0x73 )//down
{
ChangePosition(osg::Vec3 (0, -m_fMoveSpeed * sinf(osg::PI_2+m_vRotation._v[2]), 0)) ;

ChangePosition(osg::Vec3(-m_fMoveSpeed * cosf(osg::PI_2+m_vRotation._v[2]), 0, 0)) ;

return true;
}
//向左
if (ea.getKey () == 0x41||ea.getKey () == 0x61)
{
ChangePosition(osg::Vec3 (0, m_fMoveSpeed * cosf(osg::PI_2+m_vRotation._v[2]), 0)) ;

ChangePosition(osg::Vec3 (-m_fMoveSpeed * sinf(osg::PI_2+m_vRotation._v[2]), 0, 0)) ;

return true;
}
//向右
if (ea.getKey () == 0x44||ea.getKey () == 0x64) 
{
ChangePosition(osg::Vec3 (0,-m_fMoveSpeed * cosf(osg::PI_2+m_vRotation._v[2]), 0)) ;

ChangePosition(osg::Vec3 (m_fMoveSpeed * sinf(osg::PI_2+m_vRotation._v[2]), 0, 0)) ;

return true;
}
//Right
if (ea.getKey() == 0xFF53)
{
m_vRotation._v[2] -= osg::DegreesToRadians(m_fAngle);
}
//Left
if (ea.getKey()== 0xFF51)
{
m_vRotation._v[2] += osg::DegreesToRadians(m_fAngle);
}
//改变屏角
if (ea.getKey() == 0x46 || ea.getKey() == 0x66)//F
{
m_fAngle -= 0.2 ;

return true ;
}

if (ea.getKey() == 0x47 || ea.getKey() == 0x67)//G
{
m_fAngle += 0.2 ;

return true ;
}

return false;
}
//鼠标按下
case (osgGA::GUIEventAdapter ::PUSH ):

if ( ea.getButton () == 1)
{
m_fpushX = mouseX ;
m_fpushY = mouseY ;

m_bLeftButtonDown = true ;
}

return false ;

//拖动
case (osgGA::GUIEventAdapter ::DRAG ):

if ( m_bLeftButtonDown)

{
m_vRotation._v[2] -= osg::DegreesToRadians(m_fAngle * (mouseX-m_fpushX));

m_vRotation._v[0] += osg::DegreesToRadians(1.1*(mouseY-m_fpushY)) ;

if (m_vRotation._v [0] >= 3.14)
{
m_vRotation._v [0] = 3.14 ;
}

if (m_vRotation._v [0] <= 0)
{
m_vRotation._v [0] = 0 ;
}
}

return false ;
//鼠标释放
case (osgGA::GUIEventAdapter ::RELEASE ):

if ( ea.getButton () == 1)
{
m_bLeftButtonDown = false ;
}

return false ;

default:
return false;
}
}

// 位置变换函数
void TravelManipulator::ChangePosition(osg::Vec3& delta)
{
//碰撞检测
if (m_bPeng)
{
//得到新的位置
osg::Vec3 newPos1 = m_vPosition + delta;

osgUtil::IntersectVisitor ivXY; 
//根据新的位置得到两条线段检测
osg::ref_ptr<osg::LineSegment> lineXY = new osg::LineSegment(newPos1,
m_vPosition);

osg::ref_ptr<osg::LineSegment> lineZ = new osg::LineSegment(newPos1+osg::Vec3(0.0f,0.0f,10.0f),
newPos1-osg::Vec3(0.0f,0.0f,-10.0f)) ;

ivXY.addLineSegment(lineZ.get()) ;

ivXY.addLineSegment(lineXY.get()) ;
//结构交集检测
m_pHostViewer->getSceneData()->accept(ivXY) ;
//如果没有碰撞检测
if(!ivXY.hits())
{
m_vPosition += delta;
}
}
else
{
m_vPosition += delta;
}

}

//设置速度
void TravelManipulator::setSpeed (float &sp)
{
m_fMoveSpeed = sp ;
}

//得到当前速度
float TravelManipulator::getSpeed() 
{
return m_fMoveSpeed ;
}

//设置起始的位置
void TravelManipulator::SetPosition (osg::Vec3 &position)
{
m_vPosition = position ;
}

//得到当前的所在位置
osg::Vec3 TravelManipulator::GetPosition ()
{
return m_vPosition ;
}