For loop error in Display Function I have a vector saving 5 cube coordinates in oxy plan. Task: 1st cube roll 90 degrees, then disappear then 2nd cube roll 90 dg … until the last cube in the vector. Problem: whenever the program runs, all the cube will appear and roll the same time. Q: How can I solve this problem? I checked the value in for loop (temp), and value of (count) as below: angle 1 count 1 temp0 temp1 temp2 temp3 temp4 temp5 temp6 temp7 angle 2 count 2 temp0 temp1 temp2 temp3 temp4 temp5 temp6 temp7 => I do not know why the for loop does not wait for for the “presskey” action to increase the angle value before move to the next temp value. int Count(0); void Display(void) { glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glMatrixMode(GL_MODELVIEW); SetLight(); glPushMatrix(); ConclusiveAxis(); DrawGrid(); for (int temp = 0; temp < cube.coordinates.size(); temp++) { cout<< "temp" << temp << endl; if ((cube.coordinates[temp] == true)) { sDirection = true; if (Count <= 90) { glPushMatrix(); glTranslatef(cube.coordinates[temp].x - 0.5, cube.coordinates[temp].y - 0.5, 0.0); glRotatef(angle, 0, 1, 0); glTranslatef(-0.5, 0.5, 0.5); glColor3f(0.5, 1.5, 1.0); glutSolidCube(1); glPopMatrix(); } else if (Count > 90) { angle = 0; Count = 0; } else { sDirection = false; } } else { } } glPopMatrix(); glutSwapBuffers(); } void SpecialKey(unsigned char key, int x, int y) { switch (key) { case 'r': //condition for next check if (sDirection == true) { angle++; glutPostRedisplay(); Count++; cout << "angle " << angle << " count " << Count << endl; } else { glutPostRedisplay(NULL); } break; } } void OpenGLCallBackAnimation(void) { GLSettings0.PickObject = PickObject0; OpenGLInitialize(0, GLSettings0, 300, 150, 1000, 650, "window"); glutDisplayFunc(Display); glutMouseFunc(MouseButton); glutMotionFunc(OnMouseMotion); glutPassiveMotionFunc(PassiveMotion); glutKeyboardFunc(SpecialKey); //keyboard call glutMouseWheelFunc(OpenGLMouseWheel0); glutReshapeFunc(OpenGLReshape0); //glutTimerFunc(0, time_callback, 0); OpenGLPostprocessor(GLSettings0); } https://ift.tt/eA8V8J

I have a vector saving 5 cube coordinates in oxy plan. Task: 1st cube roll 90 degrees, then disappear then 2nd cube roll 90 dg … until the last cube in the vector. Problem: whenever the program runs, all the cube will appear and roll the same time. Q: How can I solve this problem? I checked the value in for loop (temp), and value of (count) as below: angle 1 count 1 temp0 temp1 temp2 temp3 temp4 temp5 temp6 temp7 angle 2 count 2 temp0 temp1 temp2 temp3 temp4 temp5 temp6 temp7 => I do not know why the for loop does not wait for for the “presskey” action to increase the angle value before move to the next temp value. int Count(0); void Display(void) { glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glMatrixMode(GL_MODELVIEW); SetLight(); glPushMatrix(); ConclusiveAxis(); DrawGrid(); for (int temp = 0; temp < cube.coordinates.size(); temp++) { cout<< "temp" << temp << endl; if ((cube.coordinates[temp] == true)) { sDirection = true; if (Count <= 90) { glPushMatrix(); glTranslatef(cube.coordinates[temp].x - 0.5, cube.coordinates[temp].y - 0.5, 0.0); glRotatef(angle, 0, 1, 0); glTranslatef(-0.5, 0.5, 0.5); glColor3f(0.5, 1.5, 1.0); glutSolidCube(1); glPopMatrix(); } else if (Count > 90) { angle = 0; Count = 0; } else { sDirection = false; } } else { } } glPopMatrix(); glutSwapBuffers(); } void SpecialKey(unsigned char key, int x, int y) { switch (key) { case 'r': //condition for next check if (sDirection == true) { angle++; glutPostRedisplay(); Count++; cout << "angle " << angle << " count " << Count << endl; } else { glutPostRedisplay(NULL); } break; } } void OpenGLCallBackAnimation(void) { GLSettings0.PickObject = PickObject0; OpenGLInitialize(0, GLSettings0, 300, 150, 1000, 650, "window"); glutDisplayFunc(Display); glutMouseFunc(MouseButton); glutMotionFunc(OnMouseMotion); glutPassiveMotionFunc(PassiveMotion); glutKeyboardFunc(SpecialKey); //keyboard call glutMouseWheelFunc(OpenGLMouseWheel0); glutReshapeFunc(OpenGLReshape0); //glutTimerFunc(0, time_callback, 0); OpenGLPostprocessor(GLSettings0); }

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