立方體旋轉 - OpenGL

Question

我喜歡openGL和旋轉的幫助。這是我的代碼：

#include <math.h> 
#include <GL/glut.h> 


float transZ=50;  
float rotateA=0;   

float rotateAspeed=0.0; 

void cube (float dimX, float dimY, float dimZ) 
{ 
    glMatrixMode(GL_MODELVIEW); 
    glPushMatrix(); 


     glTranslatef(0,dimY/2,0); 

     glScalef(dimX/2, dimY/2, dimZ/2); 


    glBegin(GL_QUADS);   
    glColor3f(0.0, 1.0, 0.0); // Color Green - TOP 

    glVertex3f(1.0, 1.0, 1.0); // TOP-RIGHT-NEAR 
    glVertex3f(-1.0, 1.0, 1.0); // TOP-LEFT-NEAR 
    glVertex3f(-1.0, 1.0, -1.0); //TOP-LEFT-FAR 
    glVertex3f(1.0, 1.0, -1.0); // TOP-RIGHT-FAR 

    glColor3f(1.0, 0.0, 0.0); // Color RED - Bottom 

    glVertex3f(1.0, -1.0, 1.0); //BOTTOM-RIGHT-NEAR 
    glVertex3f(-1.0, -1.0, 1.0); //BOTTOM-LEFT-NEAR 
    glVertex3f(-1.0, -1.0, -1.0); //BOTTOM-LEFT-FAR 
    glVertex3f(1.0, -1.0, -1.0); //BOTTOM-RIGHT-FAR 

    glColor3f(1.0, 1.0, 0.0); // Color Yellow - Back 

    glVertex3f(1.0, 1.0, -1.0); //TOP-RIGHT-FAR 
    glVertex3f(-1.0, 1.0, -1.0); //TOP-LEFT-FAR 
    glVertex3f(-1.0, -1.0, -1.0); //BOTTOM-LEFT-FAR 
    glVertex3f(1.0, -1.0, -1.0); //BOTTOM-RIGHT-FAR 

    glColor3f(0.0, 0.0, 1.0); //Color Blue - RIGHT 

    glVertex3f(1.0, 1.0, 1.0); //TOP-FRONT-NEAR 
    glVertex3f(1.0, 1.0, -1.0); //TOP-BACK-FAR 
    glVertex3f(1.0, -1.0, -1.0); //BOTTOM-BACK-FAR 
    glVertex3f(1.0, -1.0, 1.0); //BOTTOM-FRONT-NEAR 

    glColor3f(1.0, 0.5, 0.0); //Color Orange - Left 

    glVertex3f(-1.0, 1.0, 1.0); //TOP-FRONT-NEAR 
    glVertex3f(-1.0, 1.0, -1.0); //TOP-BACK-FAR 
    glVertex3f(-1.0, -1.0, -1.0);//BOTTOM-BACK-FAR 
    glVertex3f(-1.0, -1.0, 1.0); //BOTTOM-FRONT-NEAR 




    glEnd(); 


    glPopMatrix(); 
} 


void display(void) 
{ 


    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); 


    glMatrixMode(GL_MODELVIEW); 
    glLoadIdentity(); 


    gluLookAt(transZ*cos(rotateA),10,transZ*sin(rotateA), 0,10,0, 0,1,0); 


    cube(30,30,30); 


    glFlush();    

    glutSwapBuffers(); 
} 

void init (void) 
{ 
    glClearColor(1.0, 1.0, 1.0, 1.0); 
    glMatrixMode(GL_PROJECTION); 
    glLoadIdentity(); 

    glFrustum(-1, 1, -1, 1, 1, 1000); 


    glEnable(GL_DEPTH_TEST); 
} 


void keyboard(unsigned char key, int x, int y) 
{ 
    switch (key) { 
     case 27:     
     exit(0); 
     break; 
     case 'S': 
     transZ+=1.0f; 
     glutPostRedisplay(); 
     break; 
     case 'W': 
     transZ-=1.0f; 
     if (transZ<0) transZ=0; 
     glutPostRedisplay(); 
     break; 
     case 's': 
     transZ+=0.5f; 
     glutPostRedisplay(); 
     break; 
     case 'w': 
     transZ-=0.5f; 
     if (transZ<0) transZ=0; 
     glutPostRedisplay(); 
     break; 
     case 'A': 
     rotateAspeed+=0.001f; 
     glutPostRedisplay(); 
     break; 
     case 'a': 
     rotateAspeed+=0.001f; 
     glutPostRedisplay(); 
     break; 
     case 'D': 
     rotateAspeed-=0.001f; 
     glutPostRedisplay(); 
     break; 
     case 'd': 
     rotateAspeed-=0.001f; 
     glutPostRedisplay(); 
     break; 

    } 
} 

void idle(void) 
{ 
    rotateA=rotateA + rotateAspeed; 
    glutPostRedisplay();  
} 



int main(int argc, char** argv) 
{ 
    glutInit(&argc, argv); 
    glutInitDisplayMode (GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH); 
    glutInitWindowSize (500, 500); 
    glutInitWindowPosition (100, 100); 
    glutCreateWindow ("Cube"); 
    init(); 

    glutDisplayFunc(display); 
    glutIdleFunc(idle); 

    glutKeyboardFunc(keyboard); 
    glutMainLoop(); 
    return 0; 
} 

當我按下A或d立方體狀水平旋轉，但我需要使，當我按下，例如j中的立方體開始垂直地旋轉。任何幫助如何做到這一點？

Answer 1

您需要查看glRotate以及openGL中如何完成轉換。然後用三個角度參數化旋轉，稱爲​​，或使用quaternions或其他適當的旋轉表示。由此轉換將正確地旋轉立方體，它可能看起來像這樣：

glPushMatrix() 
glRotatef(alpha, 1, 0, 0); //rotate alpha around the x axis 
glRotatef(beta, 0, 1, 0); //rotate beta around the y axis 
glRotatef(gamma, 0, 0, 1); //rotate gamma around the z axis 

//dram my cube 
glPopMatrix();