openGL+VS2010的例程--空间摄影机（三维）

时间：2022-09-10 16:57:22

openGL+VS2010的例程--空间摄影机（三维）

效果图如上：

步骤：略。

实现代码如下：

1、main.cpp

  1 /**********************************************************************
  2     
  3   Camera with OpenGL
  4 
  5   June, 11th, 2000
  6 
  7   This tutorial was written by Philipp Crocoll
  8   Contact: 
  9     philipp.crocoll@web.de
 10     www.codecolony.de
 11 
 12   Every comment would be appreciated.
 13   
 14   If you want to use parts of any code of mine:
 15     let me know and
 16     use it!
 17 
 18 **********************************************************************
 19 ESC: exit
 20 
 21 CAMERA movement:
 22 w : forwards
 23 s : backwards
 24 a : turn left
 25 d : turn right
 26 x : turn up
 27 y : turn down
 28 v : strafe right
 29 c : strafe left
 30 r : move up
 31 f : move down
 32 
 33 ***********************************************************************/
 34 
 35 #include <GL\glut.h>
 36 #include <windows.h>
 37 #include "camera.h"
 38 
 39 
 40 CCamera Camera;
 41 
 42 
 43 void DrawNet(GLfloat size, GLint LinesX, GLint LinesZ)
 44 {
 45     glBegin(GL_LINES);
 46     for (int xc = 0; xc < LinesX; xc++)
 47     {
 48         glVertex3f(    -size / 2.0 + xc / (GLfloat)(LinesX-1)*size,
 49                     0.0,
 50                     size / 2.0);
 51         glVertex3f(    -size / 2.0 + xc / (GLfloat)(LinesX-1)*size,
 52                     0.0,
 53                     size / -2.0);
 54     }
 55     for (int zc = 0; zc < LinesX; zc++)
 56     {
 57         glVertex3f(    size / 2.0,
 58                     0.0,
 59                     -size / 2.0 + zc / (GLfloat)(LinesZ-1)*size);
 60         glVertex3f(    size / -2.0,
 61                     0.0,
 62                     -size / 2.0 + zc / (GLfloat)(LinesZ-1)*size);
 63     }
 64     glEnd();
 65 }
 66 
 67 void reshape(int x, int y)
 68 {
 69     if (y == 0 || x == 0) return;  //Nothing is visible then, so return
 70     
 71     //Set a new projection matrix
 72     glMatrixMode(GL_PROJECTION);  
 73     glLoadIdentity();
 74     //Angle of view:40 degrees
 75     //Near clipping plane distance: 0.5
 76     //Far clipping plane distance: 20.0
 77     gluPerspective(40.0,(GLdouble)x/(GLdouble)y,0.5,20.0);
 78 
 79     glMatrixMode(GL_MODELVIEW);
 80     glViewport(0,0,x,y);  //Use the whole window for rendering
 81 }
 82 
 83 void Display(void)
 84 {
 85     glClear(GL_COLOR_BUFFER_BIT);
 86     glLoadIdentity();
 87     Camera.Render();
 88     glTranslatef(0.0,0.8,0.0);
 89 
 90     glScalef(3.0,1.0,3.0);
 91     
 92     GLfloat size = 2.0;
 93     GLint LinesX = 30;
 94     GLint LinesZ = 30;
 95     
 96     GLfloat halfsize = size / 2.0;
 97     glColor3f(1.0,1.0,1.0);
 98     glPushMatrix();
 99         glTranslatef(0.0,-halfsize ,0.0);
100         DrawNet(size,LinesX,LinesZ);
101         glTranslatef(0.0,size,0.0);
102         DrawNet(size,LinesX,LinesZ);
103     glPopMatrix();
104     glColor3f(0.0,0.0,1.0);
105     glPushMatrix();
106         glTranslatef(-halfsize,0.0,0.0);    
107         glRotatef(90.0,0.0,0.0,halfsize);
108         DrawNet(size,LinesX,LinesZ);
109         glTranslatef(0.0,-size,0.0);
110         DrawNet(size,LinesX,LinesZ);
111     glPopMatrix();
112     glColor3f(1.0,0.0,0.0);
113     glPushMatrix();
114         glTranslatef(0.0,0.0,-halfsize);    
115         glRotatef(90.0,halfsize,0.0,0.0);
116         DrawNet(size,LinesX,LinesZ);
117         glTranslatef(0.0,size,0.0);
118         DrawNet(size,LinesX,LinesZ);
119     glPopMatrix();
120         
121     glFlush();  
122     glutSwapBuffers();
123 
124 }
125 void KeyDown(unsigned char key, int x, int y)
126 {
127     switch (key) 
128     {
129     case 27:        //ESC
130         PostQuitMessage(0);
131         break;
132     case 'a':        
133         Camera.RotateY(5.0);
134         Display();
135         break;
136     case 'd':        
137         Camera.RotateY(-5.0);
138         Display();
139         break;
140     case 'w':        
141         Camera.MoveForwards( -0.1 ) ;
142         Display();
143         break;
144     case 's':        
145         Camera.MoveForwards( 0.1 ) ;
146         Display();
147         break;
148     case 'x':        
149         Camera.RotateX(5.0);
150         Display();
151         break;
152     case 'y':        
153         Camera.RotateX(-5.0);
154         Display();
155         break;
156     case 'c':        
157         Camera.StrafeRight(-0.1);
158         Display();
159         break;
160     case 'v':        
161         Camera.StrafeRight(0.1);
162         Display();
163         break;
164     case 'f':
165         Camera.Move(F3dVector(0.0,-0.3,0.0));
166         Display();
167         break;
168     case 'r':
169         Camera.Move(F3dVector(0.0,0.3,0.0));
170         Display();
171         break;
172 
173     }
174 }
175 
176 int main(int argc, char **argv)
177 {
178     glutInit(&argc, argv);
179     glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB);
180     glutInitWindowSize(300,300);
181     glutCreateWindow("Camera");
182     Camera.Move( F3dVector(0.0, 0.0, 3.0 ));
183     Camera.MoveForwards( 1.0 );
184     glutDisplayFunc(Display);
185     glutReshapeFunc(reshape);
186     glutKeyboardFunc(KeyDown);
187     glutMainLoop();
188     return 0;             
189 }

2、camera.cpp

  1 #include "camera.h"
  2 #include "math.h"
  3 #include <iostream>
  4 #include "windows.h"
  5 
  6 SF3dVector F3dVector ( GLfloat x, GLfloat y, GLfloat z )
  7 {
  8     SF3dVector tmp;
  9     tmp.x = x;
 10     tmp.y = y;
 11     tmp.z = z;
 12     return tmp;
 13 }
 14 SF3dVector AddF3dVectors (SF3dVector* u, SF3dVector* v)
 15 {
 16     SF3dVector result;
 17     result.x = u->x + v->x;
 18     result.y = u->y + v->y;
 19     result.z = u->z + v->z;
 20     return result;
 21 }
 22 void AddF3dVectorToVector ( SF3dVector * Dst, SF3dVector * V2)
 23 {
 24     Dst->x += V2->x;
 25     Dst->y += V2->y;
 26     Dst->z += V2->z;
 27 }
 28 
 29 
 30 /***************************************************************************************/
 31 
 32 CCamera::CCamera()
 33 {
 34     //Init with standard OGL values:
 35     Position = F3dVector (    0.0, 
 36                             0.0,
 37                             0.0);
 38     ViewDir = F3dVector(    0.0,
 39                             0.0,
 40                             -1.0);
 41     ViewDirChanged = false;
 42     //Only to be sure:
 43     RotatedX = RotatedY = RotatedZ = 0.0;
 44 }
 45 
 46 void CCamera::GetViewDir( void )
 47 {
 48     SF3dVector Step1, Step2;
 49     //Rotate around Y-axis:
 50     Step1.x = cos( (RotatedY + 90.0) * PIdiv180);
 51     Step1.z = -sin( (RotatedY + 90.0) * PIdiv180);
 52     //Rotate around X-axis:
 53     double cosX = cos (RotatedX * PIdiv180);
 54     Step2.x = Step1.x * cosX;
 55     Step2.z = Step1.z * cosX;
 56     Step2.y = sin(RotatedX * PIdiv180);
 57     //Rotation around Z-axis not yet implemented, so:
 58     ViewDir = Step2;
 59 }
 60 void CCamera::Move (SF3dVector Direction)
 61 {
 62     AddF3dVectorToVector(&Position, &Direction );
 63 }
 64 
 65 void CCamera::RotateY (GLfloat Angle)
 66 {
 67     RotatedY += Angle;
 68     ViewDirChanged = true;
 69 }
 70 
 71 void CCamera::RotateX (GLfloat Angle)
 72 {
 73     RotatedX += Angle;
 74     ViewDirChanged = true;
 75 }
 76 
 77 void CCamera::Render( void )
 78 {
 79     glRotatef(-RotatedX , 1.0, 0.0, 0.0);
 80     glRotatef(-RotatedY , 0.0, 1.0, 0.0);
 81     glRotatef(-RotatedZ , 0.0, 0.0, 1.0);
 82     glTranslatef( -Position.x, -Position.y, -Position.z );
 83 }
 84 
 85 void CCamera::MoveForwards( GLfloat Distance )
 86 {
 87     if (ViewDirChanged) GetViewDir();
 88     SF3dVector MoveVector;
 89     MoveVector.x = ViewDir.x * -Distance;
 90     MoveVector.y = ViewDir.y * -Distance;
 91     MoveVector.z = ViewDir.z * -Distance;
 92     AddF3dVectorToVector(&Position, &MoveVector );
 93 }
 94 
 95 void CCamera::StrafeRight ( GLfloat Distance )
 96 {
 97     if (ViewDirChanged) GetViewDir();
 98     SF3dVector MoveVector;
 99     MoveVector.z = -ViewDir.x * -Distance;
100     MoveVector.y = 0.0;
101     MoveVector.x = ViewDir.z * -Distance;
102     AddF3dVectorToVector(&Position, &MoveVector );
103 }

2、camera.h

 1 #include <gl\glut.h>        // Need to include it here because the GL* types are required
 2 #define PI 3.1415265359
 3 #define PIdiv180 3.1415265359/180.0
 4 
 5 /////////////////////////////////
 6 //Note: All angles in degrees  //
 7 /////////////////////////////////
 8 
 9 struct SF3dVector  //Float 3d-vect, normally used
10 {
11     GLfloat x,y,z;
12 };
13 struct SF2dVector
14 {
15     GLfloat x,y;
16 };
17 
18 class CCamera
19 {
20 private:
21     SF3dVector Position;
22     SF3dVector ViewDir;        /*Not used for rendering the camera, but for "moveforwards"
23                             So it is not necessary to "actualize" it always. It is only
24                             actualized when ViewDirChanged is true and moveforwards is called*/
25     bool ViewDirChanged;
26     GLfloat RotatedX, RotatedY, RotatedZ;    
27     void GetViewDir ( void );
28 public:
29     CCamera();                //inits the values (Position: (0|0|0) Target: (0|0|-1) )
30     void Render ( void );    //executes some glRotates and a glTranslate command
31                             //Note: You should call glLoadIdentity before using Render
32     void Move ( SF3dVector Direction );
33     void RotateX ( GLfloat Angle );
34     void RotateY ( GLfloat Angle );
35     void RotateZ ( GLfloat Angle );
36     void RotateXYZ ( SF3dVector Angles );
37     void MoveForwards ( GLfloat Distance );
38     void StrafeRight ( GLfloat Distance );
39 };
40 
41 
42 SF3dVector F3dVector ( GLfloat x, GLfloat y, GLfloat z );
43 SF3dVector AddF3dVectors ( SF3dVector * u, SF3dVector * v);
44 void AddF3dVectorToVector ( SF3dVector * Dst, SF3dVector * V2);

以上代码来源：http://www.codecolony.de/

 

标签：

相关文章