[OpenGL] Ansicht drehen

[phibos]

Also ich habe folgenden leicht geänderten Code von einem Tutorial .

#include <GL/gl.h>
#include <GL/glu.h>
#include <GL/glut.h>
#include <stdio.h>
#include <iostream>
using namespace std; /* GLU extention library */

void init(void);
void display(void);
void keyboard(unsigned char, int, int);
void resize(int, int);
void drawcube(int, int, int);

int is_depth; /* depth testing flag */

int main (int argc, char **argv)
{
        glutInit(&argc, argv);
        glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB);
        glutInitWindowSize(600, 600);
        glutInitWindowPosition(40, 40);
        glutCreateWindow("The Cube World");
        init();
        glutDisplayFunc(display);
        glutKeyboardFunc(keyboard);

        /* this time we're going to keep the aspect ratio
        constant by trapping the window resizes */
        glutReshapeFunc(resize);  

        glutMainLoop();
        return 0;
}

void init(void)
{
        glClearColor(0.0, 0.0, 0.0, 0.0);
        glEnable(GL_DEPTH_TEST);
        is_depth = 1;
        glMatrixMode(GL_MODELVIEW);
}

void display(void)
{
        if (is_depth)
                glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
        else
                glClear(GL_COLOR_BUFFER_BIT);
        /* draw the floor */
        glBegin(GL_QUADS);
                glColor3f(0.2f, 0.2f, 0.2f);
                glVertex3f(-100.0, 0.0, -100.0);
                glColor3f(0.4f, 0.4f, 0.4f);
                glVertex3f(-100.0, 0.0, 100.0);
                glColor3f(0.6f, 0.6f, 0.6f);
                glVertex3f(100.0, 0.0, 100.0);
                glColor3f(0.8f, 0.8f, 0.8f);
                glVertex3f(100.0, 0.0, -100.0);         
        glEnd();
        /* draw 12 cubes with different colors */
        drawcube(75, 57, 2);
        drawcube(-65, -12, 3);
        drawcube(50, -50, 1);
        drawcube(-56, 17, 2);
        drawcube(67, 12, 3);
        drawcube(-87, 32, 1);
        drawcube(-26, 75, 2);
        drawcube(57, 82, 3);
        drawcube(-3, 12, 1);
        drawcube(46, 35, 2);
        drawcube(37, -2, 3);
        glutSwapBuffers();
}

void keyboard(unsigned char key, int x, int y)
{
        /* This time the controls are:

          "a": move left
          "d": move right
          "w": move forward
          "s": move back
          "t": toggle depth-testing

        */
        switch (key)
        {
        case 'a':
        case 'A':
                glTranslatef(5.0, 0.0, 0.0);
                break;
        case 'd':
        case 'D':
                glTranslatef(-5.0, 0.0, 0.0);
                break;
        case 'w':
        case 'W':
                glTranslatef(0.0, 0.0, 5.0);
                break;
        case 's':
        case 'S':
                glTranslatef(0.0, 0.0, -5.0);
                break;
        case 'q':
                 glTranslatef(0.0, 5.0, 0.0);
                 break;
        case 'e':
                 glTranslatef(0.0,-5.0,0.0);
                 break;
        case 'f':
                 //FIXME 
                 break;
        case 't':
        case 'T':
                if (is_depth)
                {
                        is_depth = 0;
                        glDisable(GL_DEPTH_TEST);
                }
                else
                {
                        is_depth = 1;
                        glEnable(GL_DEPTH_TEST);
                }
        }
        display();
}

void resize(int width, int height)
{
        if (height == 0) height = 1;

        glMatrixMode(GL_PROJECTION);
        glLoadIdentity();

        /* note we divide our width by our height to get the aspect ratio */
        gluPerspective(45.0, width / height, 1.0, 400.0);

        /* set initial position */
        glTranslatef(0.0, -5.0, -150.0);

        glMatrixMode(GL_MODELVIEW);
}

void drawcube(int x_offset, int z_offset, int color)
{
        /* this function draws a cube centerd at (x_offset, z_offset)
        x and z _big are the back and rightmost points, x and z _small are
        the front and leftmost points */
        float x_big = (float)x_offset + 5;
        float z_big = (float)z_offset + 5;
        float x_small = (float)x_offset - 5;
        float z_small = (float)z_offset - 5;
        switch(color)
        {
        case 1:
                glColor3f(1.0,0.0,0.0);
                break;
        case 2:
                glColor3f(0.0,1.0,0.0);
                break;
        case 3:
                glColor3f(0.0,0.0,1.0);
                break;
        }
        glBegin(GL_QUADS);
                glVertex3f(x_small,10.0,z_big); /* front */
                glVertex3f(x_small,0.0,z_big);
                glVertex3f(x_big,0.0,z_big);
                glVertex3f(x_big,10.0,z_big);

                glVertex3f(x_big,10.0,z_small); /* back */
                glVertex3f(x_big,0.0,z_small);
                glVertex3f(x_small,0.0,z_small);
                glVertex3f(x_small,10.0,z_small);

                glVertex3f(x_big,10.0,z_big); /* right */
                glVertex3f(x_big,0.0,z_big);
                glVertex3f(x_big,0.0,z_small);
                glVertex3f(x_big,10.0,z_small);

                glVertex3f(x_small,10.0,z_small); /* left */
                glVertex3f(x_small,0.0,z_small);
                glVertex3f(x_small,0.0,z_big);
                glVertex3f(x_small,10.0,z_big);

                glVertex3f(x_small,10.0,z_big); /* top */
                glVertex3f(x_big,10.0,z_big);
                glVertex3f(x_big,10.0,z_small);
                glVertex3f(x_small,10.0,z_small);

                glVertex3f(x_small,0.0,z_small); /* bottom */
                glVertex3f(x_big,0.0,z_small);
                glVertex3f(x_big,0.0,z_big);
                glVertex3f(x_small,0.0,z_big);
        glEnd();
}

Ich möchte wenn der Benutzer f drückt dass sich die Welt um 90 Grad dreht , dachte zuerst da könnte ich mit glrotatef machen allerdings geht das nicht da dann die Steuerung nicht mehr richtig funktioniert ...
Wäre sehr dankbar wenn mir jemand sagen könnte wie ich das am besten mache .

Danke

[Krux]

glRotatef ist schon richtig, aber überleg mal, wo es hinkommt.

Ich würd die Positionen der Kamera übrigens in Variablen speichern, und dann für jeden Frame mit glLoadIdentety() und gluLookAt(...) abrufen.