Hi all,
I am a beginner of OpenGL, and I am practicing with gluLookAt(). I want to see that when I change the eye position of gluLookAt(), then the 3D figure shown on the screen changed accordingly (smaller or bigger, rotate left/right/up/down). However, it doesn’t. No matter what value I set for the eye position, the figure always appears to be the same.
The following is my code related with gluLookAt():
void
reshape(int w, int h){
glViewport( 0, 0, (GLsizei) w, (GLsizei)h );
glMatrixMode( GL_PROJECTION );
glLoadIdentity();
gluPerspective( 65.0, (GLfloat) w / h, 1.0, 100.0 );
glMatrixMode( GL_MODELVIEW );
glLoadIdentity();
gluLookAt( 0.0, 0.0, 5.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0 );
}
void
display(void){
glClear(GL_COLOR_BUFFER_BIT);
glClearColor(1.0f, 0.65f, 0.0f, 0.5f);
glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
gluLookAt( 100, 0, 0, 0, -0.456398, 1 , 0, 1, 0 );
glLoadIdentity();
glPushMatrix();
glBegin(GL_TRIANGLES);
//a set of vertex for the triangles
glEnd();
glPopMatrix();
glutSwapBuffers();
glReadBuffer( GL_FRONT );
}
May I ask what did I do wrong?
Thank you very much.