Question

我正在创建一个简单的纹理立方体但我的键盘功能有问题我似乎没有互动，我希望立方体在x和y方向移动，但它不移动，我使用此功能

void specialKeys( int key, int x, int y ) {
  if (key == GLUT_KEY_RIGHT)
    rotate_y += 5;
  else if (key == GLUT_KEY_LEFT)
    rotate_y -= 5;
  else if (key == GLUT_KEY_UP)
    rotate_x += 5;
  else if (key == GLUT_KEY_DOWN)
    rotate_x -= 5;
  glutPostRedisplay();

}

在我的主要功能中我使用了这段代码

glutSpecialFunc(specialKeys);

这是我的整个代码

 #include <stdlib.h>
#include <GL/glut.h>
#include "RgbImage.h"

void specialKeys();
double rotate_y=0; 
double rotate_x=0;
GLfloat xRotated, yRotated, zRotated;
GLuint  texture[1];         // Storage For One Texture ( NEW )
void loadTextureFromFile(char *filename)
{   
   glClearColor (0.0, 0.0, 0.0, 0.0);
   glShadeModel(GL_FLAT);
   glEnable(GL_DEPTH_TEST);
   RgbImage theTexMap( filename );  
    glGenTextures(1, &texture[0]);                  // Create The Texture
        glBindTexture(GL_TEXTURE_2D, texture[0]);
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);

        // Typical Texture Generation Using Data From The Bitmap

        glTexImage2D(GL_TEXTURE_2D, 0, 3, theTexMap.GetNumCols(), theTexMap.GetNumRows(), 0, GL_RGB, GL_UNSIGNED_BYTE, theTexMap.ImageData() );

}
void drawScene(void)
{
   glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
   glEnable(GL_TEXTURE_2D);
    glBindTexture(GL_TEXTURE_2D, texture[0]);
   glLoadIdentity();
   glTranslatef(0.0,0.0,-5);
     glRotatef(yRotated, 0, 1, 0);
     glRotatef(zRotated, 0, 0, 1);

  glBegin(GL_QUADS);
        // Front Face

        // Back Face
        glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f);
        glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f,  1.0f, -1.0f);
        glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f,  1.0f, -1.0f);
        glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f);
        // Top Face

        // Bottom Face
        glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, -1.0f, -1.0f);
        glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f, -1.0f, -1.0f);
        glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f,  1.0f);
        glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f,  1.0f);
        // Right face
        glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f);
        glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f,  1.0f, -1.0f);
        glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f,  1.0f,  1.0f);
        glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f,  1.0f);
        // Left Face
        glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f);
        glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f,  1.0f);
        glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f,  1.0f,  1.0f);
        glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f,  1.0f, -1.0f);
    glEnd();

   glFlush();
   glDisable(GL_TEXTURE_2D);

}

void resizeWindow(int x, int y)
{
 if (y == 0 || x == 0) return;
    glMatrixMode(GL_PROJECTION);  
    glLoadIdentity();     
    gluPerspective(40.0,(GLdouble)x/(GLdouble)y,0.5,20.0);
    glMatrixMode(GL_MODELVIEW);
    glViewport(0,0,x,y);
}

void specialKeys( int key, int x, int y ) {
  if (key == GLUT_KEY_RIGHT)
    rotate_y += 5;
  else if (key == GLUT_KEY_LEFT)
    rotate_y -= 5;
  else if (key == GLUT_KEY_UP)
    rotate_x += 5;
  else if (key == GLUT_KEY_DOWN)
    rotate_x -= 5;
  glutPostRedisplay();

}
char* filename = "./salt_on_spoon.bmp";

int main(int argc, char** argv)
{
   glutInit(&argc, argv);
   glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);
   glutInitWindowSize(240, 240);
   glutInitWindowPosition(100, 100);
   glutCreateWindow(argv[0]);
   loadTextureFromFile( filename );
   glutDisplayFunc(drawScene);
   glutSpecialFunc(specialKeys);
   glutReshapeFunc(resizeWindow);
   glutMainLoop();
   return 0;
}

Answer 1

您的回调正在修改rotate_x和rotate_y，但您正在使用不同的变量进行轮换：

glRotatef(yRotated, 0, 1, 0);
glRotatef(zRotated, 0, 0, 1);

Answer 2

试试这个：

#include <GL/glut.h>

GLfloat pos_x = 0, pos_y = 0;
void specialKeys( int key, int x, int y ) 
{
    const float step = 0.01;
    if (key == GLUT_KEY_RIGHT)
        pos_x += step;
    else if (key == GLUT_KEY_LEFT)
        pos_x -= step;
    else if (key == GLUT_KEY_UP)
        pos_y += step;
    else if (key == GLUT_KEY_DOWN)
        pos_y -= step;
    glutPostRedisplay();
}

void drawScene(void)
{
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    glMatrixMode(GL_PROJECTION);  
    glLoadIdentity();    
    double x = glutGet( GLUT_WINDOW_WIDTH );
    double y = glutGet( GLUT_WINDOW_HEIGHT );
    gluPerspective(40.0,x/y,0.5,20.0);

    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
    glTranslatef(0.0,0.0,-5);

    glTranslatef( pos_x, pos_y, 0 );
    glBegin(GL_QUADS);
    // Front Face

    // Back Face
    glColor3ub(255,0,0);
    glVertex3f(-1.0f, -1.0f, -1.0f);
    glVertex3f(-1.0f,  1.0f, -1.0f);
    glVertex3f( 1.0f,  1.0f, -1.0f);
    glVertex3f( 1.0f, -1.0f, -1.0f);
    // Top Face

    // Bottom Face
    glColor3ub(0,255,0);
    glVertex3f(-1.0f, -1.0f, -1.0f);
    glVertex3f( 1.0f, -1.0f, -1.0f);
    glVertex3f( 1.0f, -1.0f,  1.0f);
    glVertex3f(-1.0f, -1.0f,  1.0f);
    // Right face
    glColor3ub(0,0,255);
    glVertex3f( 1.0f, -1.0f, -1.0f);
    glVertex3f( 1.0f,  1.0f, -1.0f);
    glVertex3f( 1.0f,  1.0f,  1.0f);
    glVertex3f( 1.0f, -1.0f,  1.0f);
    // Left Face
    glColor3ub(255,255,255);
    glVertex3f(-1.0f, -1.0f, -1.0f);
    glVertex3f(-1.0f, -1.0f,  1.0f);
    glVertex3f(-1.0f,  1.0f,  1.0f);
    glVertex3f(-1.0f,  1.0f, -1.0f);
    glEnd();

    glFlush();
}

int main(int argc, char** argv)
{
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);
    glutInitWindowSize(240, 240);
    glutInitWindowPosition(100, 100);
    glutCreateWindow(argv[0]);
    glutDisplayFunc(drawScene);
    glutSpecialFunc(specialKeys);
    glutMainLoop();
    return 0;
}

如何使用键盘上的按键功能旋转立方体

2 个答案: