计算机图形学实验四

#include <gl/glut.h>

static GLsizei iMode = 1;

static GLfloat xRot = 0.0f; 

static GLfloat yRot = 0.0f; 

int winWidth = 400, winHeight = 200;

int iPointNum = 0;  

int x1=0,x2=0,y1=0,y2=0;

GLuint Cube;

 

void initial(void)

{

      

              glClearColor(1.0, 1.0, 1.0, 1.0);  

              glMatrixMode (GL_PROJECTION);

              glLoadIdentity();

              gluOrtho2D(-3.0, 3.0, -3.0,3.0);

 

              Cube=glGenLists(1);

 

       glNewList(Cube,GL_COMPILE);

 

           glBegin(GL_TRIANGLE_FAN);

              glShadeModel(GL_FLAT);

              glColor3f(1.0,0.0,0.0); 

           glVertex3f(1,1,1);

                     glVertex3f(2,0,0);

                     glVertex3f(2,1,0);  

              glEnd();

 

              glBegin(GL_TRIANGLE_FAN); 

              glShadeModel(GL_FLAT);

              glColor3f(1.0,1.0,0.0);

               glVertex3f(1,1,1);

                     glVertex3f(0,1,0);

                     glVertex3f(2,1,0);

           glEnd();

             

              glBegin(GL_TRIANGLE_FAN);

              glShadeModel(GL_FLAT);

              glColor3f(0.0,0.0,1.0);

               glVertex3f(1,1,1);

                     glVertex3f(0,1,0);

                     glVertex3f(2,0,0);

              glEnd();

             

              glBegin(GL_TRIANGLE_FAN);

              glShadeModel(GL_FLAT);

              glColor3f(0.0,1.0,0.0);

                  glVertex3f(0,1,0);

                     glVertex3f(2,0,0);

                     glVertex3f(2,1,0);

           glEnd();

 

           glEndList();

}

 

void triangle (GLsizei mode)

{

              if(mode == 1)   

              {

                     glPolygonMode(GL_FRONT_AND_BACK,GL_LINE);

                     glMatrixMode(GL_PROJECTION);

                     glLoadIdentity();

                     gluOrtho2D(-5.0,5.0,-5.0,5.0);

                     glMatrixMode(GL_MODELVIEW);

                     glPushMatrix();

                     glLoadIdentity();

                  switch(iMode){

                          case 1:glCallList(Cube);break;

                             case 2:glRotatef(-90.0,1.0,0.0,0.0);glCallList(Cube);break;

                             case 3:glRotatef(90.0,0.0,1.0,0.0);glCallList(Cube);break;

                     }

                     glPopMatrix();

              }

              else

              {

                     glPolygonMode(GL_FRONT_AND_BACK,GL_FILL);

                  glMatrixMode(GL_PROJECTION);

                     glLoadIdentity();

                     gluPerspective(45.0f,1,1.0f,100.0f);

                     gluLookAt(0,0,-10,0,0,0,0,1,0);

                     glMatrixMode(GL_MODELVIEW);

                     glPushMatrix();

                     glRotatef(xRot,1.0f,0.0f,0.0f);

                     glRotatef(yRot,0.0f,1.0f,0.0f);

                     glCallList(Cube);

                     glPopMatrix();

                  glRotatef(xRot, 1.0f, 0.0f, 0.0f); 

                  glRotatef(yRot, 0.0f, 1.0f, 0.0f);

              }

}

 

void Display(void)

{

              glClear(GL_COLOR_BUFFER_BIT);

              glViewport(0, 0, 200, 200);

              triangle(1);

 

              glViewport(200, 0, 200, 200);

              triangle(2);

 

              glFlush();

}

 

void PassiveMouseMove (GLint xMouse, GLint yMouse)

{

       if(iPointNum == 1)       {

              x2 = xMouse;

              y2 = winHeight - yMouse;    

           if(y2<=y1)     xRot -= 0.05f;

              if(y2>=y1)     xRot += 0.05f;

              if(x2>=x1)     yRot -= 0.05f;

              if(x2<=x1)     yRot += 0.05f;

              if(xRot > 356.0f)   xRot = 0.0f;

              if(xRot < -1.0f)      xRot = 355.0f;

              if(yRot > 356.0f)   yRot = 0.0f;

              if(yRot < -1.0f)      yRot = 355.0f;

              glutPostRedisplay();

       }    

}

 

void ProcessMenu(int value)

{

              iMode = value; 

              glutPostRedisplay();

}

 

void MousePlot(GLint button, GLint action, GLint xMouse, GLint yMouse)

{

       if(button == GLUT_LEFT_BUTTON && action == GLUT_DOWN)       {

              if(iPointNum == 0 || iPointNum == 2){

                     iPointNum = 1;

                     x1 = xMouse;         y1 = winHeight - yMouse;

              }

              else{

                     iPointNum = 2;

                     x2 = xMouse;         y2 = winHeight - yMouse;

              glutPostRedisplay();                

              }

       }

       if(button == GLUT_RIGHT_BUTTON && action == GLUT_DOWN){

              iPointNum = 0;

              glutPostRedisplay();

       }

}

void main()

{

              glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);

              glutInitWindowPosition(100, 100);

              glutInitWindowSize(400,200);

              glutCreateWindow("实验四-三视图与旋转");

 

              int nMainMenu = glutCreateMenu(ProcessMenu);

              glutAddMenuEntry("正视图",1);

              glutAddMenuEntry("俯视图", 2);

              glutAddMenuEntry("侧视图", 3);

              glutAttachMenu(GLUT_RIGHT_BUTTON);

 

           glutMouseFunc(MousePlot);                

           glutPassiveMotionFunc(PassiveMouseMove);  

              initial();

              glutDisplayFunc(Display);

              glutMainLoop();

}