How to make one object "orbit" another object? - c++

Question

I'm currently working on a project involving two cubes. The first cube meant to be static, while the second is going to rotate, or orbit, around the first. I'm very new to OpenGL programming, so I'm having quite a bit of difficulty getting this to work. Can anyone point me in the right direction? So far, I just have two cubes, but I am unable to get them to move as if they were animated. Here is my code if you would like to offer suggestions. Thank you so much!
Main:
#include "vgl.h"
#include <glm/glm.hpp>
#include <glm/gtc/matrix_transform.hpp>
#include <glm/gtc/type_ptr.hpp>
#include <iostream>
#include <vector>
#include "Box.h"
#include "Camera.h"
#include "VertexBufferData.h"
#include <glm/gtc/quaternion.hpp>
#include <glm/gtx/quaternion.hpp>
using namespace std;
using namespace glm;
#define SPACEBAR_KEY 32
#define ESCAPE_KEY 033
Camera* camera;
vector<Box * > gameObjects;
bool keyDown[255];
void CheckKeyboard(){
if (keyDown['a'])
camera->RotateLeft();
if (keyDown['d'])
camera->RotateRight();
if (keyDown['w'])
camera->MoveForward();
if (keyDown['s'])
camera->MoveBackWard();
if (keyDown['e'])
camera->StrafeRight();
if (keyDown['q'])
camera->StrafeLeft();
}
void closeApp()
{
delete camera;
for (auto it = gameObjects.begin(); it != gameObjects.end(); ++it) {
delete (*it);
}
}
void keyboard(unsigned char key, int x, int y)
{
switch (key)
{
case ESCAPE_KEY: // ASCII Escape Key Code
closeApp();
exit(EXIT_SUCCESS);
break;
default:
keyDown[key] = true;
}
glutPostRedisplay();
}
void keyboardUp(unsigned char key, int x, int y)
{
keyDown[key] = false;
}
void mouseWheel(int button, int direction, int x, int y)
{
if (button == 16)
camera->ResetFOV();
else if (direction > 0)
camera->ZoomIn();
else
camera->ZoomOut();
}
void mouseMovement(int x, int y)
{
static bool warp = true;
if (warp)
{
if (x>glutGet(GLUT_WINDOW_WIDTH) / 2)
camera->RotateRight();
else if (x<glutGet(GLUT_WINDOW_WIDTH) / 2)
camera->RotateLeft();
if (y>glutGet(GLUT_WINDOW_HEIGHT) / 2)
camera->RotateUp();
else if (y<glutGet(GLUT_WINDOW_HEIGHT) / 2)
camera->RotateDown();
glutWarpPointer(glutGet(GLUT_WINDOW_WIDTH) / 2, glutGet(GLUT_WINDOW_HEIGHT) / 2);
warp = false;
}
else
warp = true;
}
void timer(int value)
{
glutPostRedisplay();
glutTimerFunc(25, timer, 0);
}
void display()
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
CheckKeyboard();
camera->Update();
for (auto it = gameObjects.begin(); it != gameObjects.end(); ++it) {
(*it)->shaderProgram->bindShader();
glm::mat4 MVP = camera->ProjectionMatrix * camera->ViewMatrix * (*it)->getModelMatrix();
(*it)->shaderProgram->sendUniform4x4("MVP", glm::value_ptr(MVP));
(*it)->Draw();
}
glutSwapBuffers();
}
void init()
{
int i = 0, forever = 0;
camera = new Camera();
memset(keyDown, false, sizeof(keyDown));
glClearColor(0.0f, 0.0f, 0.4f, 0.0f);
glutWarpPointer(glutGet(GLUT_WINDOW_WIDTH) / 2, glutGet(GLUT_WINDOW_HEIGHT) / 2);
glutSetCursor(GLUT_CURSOR_FULL_CROSSHAIR);
glEnable(GL_DEPTH_TEST);
glDepthFunc(GL_LEQUAL);
glEnable(GL_CULL_FACE);
VertexBufferData vertexBufferData = VertexBufferData("Data\\Models\\Objects.xml");
gameObjects.push_back(new Box(vertexBufferData, glm::vec3(-2.0f, 0.0f, 0.0f), "Data\\Shaders\\Vertex.shader", "Data\\Shaders\\Fragment.shader"));
gameObjects.push_back(new Box(vertexBufferData, glm::vec3(2.0f, 0.0f, 0.0f), "Data\\Shaders\\Vertex.shader", "Data\\Shaders\\Fragment.shader"));
gameObjects[1]->setRotation(45.0f, vec3(0.0f, 0.0f, 1.0f));
gameObjects[0]->setScaleMatrix(vec3(2, 2, 2));
}
int main(int argc, char** argv)
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_RGBA | GLUT_DEPTH);
glutInitWindowSize(1024, 768);
glutInitContextProfile(GLUT_CORE_PROFILE);
glutCreateWindow("Satterwhite_Project_3");
if (glewInit())
{
cerr << "Unable to init glew" << endl;
exit(EXIT_FAILURE);
}
init();
glutDisplayFunc(display);
glutKeyboardFunc(keyboard);
glutKeyboardUpFunc(keyboardUp);
glutPassiveMotionFunc(mouseMovement);
glutMouseWheelFunc(mouseWheel);
glutTimerFunc(25, timer, 0);
glutMainLoop();
return 0;
}
Box.cpp
#include "Box.h"
Box::Box(VertexBufferData &vbd, vec3 initialPosition,const string vertexShader, const string fragmentShader):GameObject(vertexShader, fragmentShader)
{
Position=initialPosition;
vertexBufferData =vbd;
RotationMatrix=mat4(1.0f);
OrbitMatrix = mat4(1.0f);
ScaleMatrix=mat4(1.0f);
TranslationMatrix =translate(glm::mat4(1.0f), Position);
if (!shaderProgram->initialize())
{
std::cerr << "Could not initialize the shaders" << std::endl;
}
shaderProgram->bindShader();
glGenVertexArrays(1, &VAO);
glBindVertexArray(VAO);
glGenBuffers(1, &vertexBuffer);
glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer);
glBufferData(GL_ARRAY_BUFFER, vertexBufferData.verticiesSize, &vertexBufferData.verticies[0], GL_STATIC_DRAW);
glGenBuffers(1, &fragmentBuffer);
glBindBuffer(GL_ARRAY_BUFFER, fragmentBuffer);
glBufferData(GL_ARRAY_BUFFER, vertexBufferData.colorSize, &vertexBufferData.colors[0], GL_STATIC_DRAW);
shaderProgram->linkProgram();
}
void Box::setRotation(float degrees, vec3 axis)
{
RotationMatrix=rotate(glm::mat4(1.0f), degrees, axis);
RotationMatrix=rotate(RotationMatrix, degrees, vec3(1.0f,0.0f,0.0f));
}
void Box::setScaleMatrix(vec3 scale)
{
ScaleMatrix = glm::scale(mat4(1.0f), scale);
}
/*void Box::setOrbitMatrix(vec3 Position, vec3 axis)
{
OrbitMatrix =
}*/
void Box::Draw()
{
shaderProgram->bindShader();
glEnableVertexAttribArray(0);
glEnableVertexAttribArray(1);
glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer);
glVertexAttribPointer(0, 3, GL_FLOAT,GL_FALSE, 0, BUFFER_OFFSET(0));
glBindBuffer(GL_ARRAY_BUFFER, fragmentBuffer);
glVertexAttribPointer(1, 3, GL_FLOAT,GL_FALSE, 0, BUFFER_OFFSET(0));
glDrawArrays(GL_TRIANGLES, 0, vertexBufferData.verticies.size());
glDisableVertexAttribArray(0);
glDisableVertexAttribArray(1);
}
Box.h
#pragma once
#include "GameObject.h"
class Box : public GameObject
{
private:
mat4 ModelMatrix;
mat4 RotationMatrix;
mat4 OrbitMatrix;
mat4 TranslationMatrix;
mat4 ScaleMatrix;
public:
void Draw();
virtual ObjectType getType() const { return BOX; }
mat4 getModelMatrix() {return TranslationMatrix*RotationMatrix*ScaleMatrix;}
mat4 getMRotationMatrix() {return RotationMatrix;}
mat4 getTranslationMatrix() {return TranslationMatrix;}
mat4 getOrbitMatrix(){ return OrbitMatrix; }
mat4 getScaleMatrix() {return ScaleMatrix;}
void setRotation(float degrees, vec3 axis);
void setScaleMatrix(vec3 scale);
void setOrbitMatrix(vec3 Position, vec3 axis);
Box(VertexBufferData &vertexBufferData, vec3 initialPosition, const string vertexShader, const string fragmentShader);
vec3 Position;
mat4 rot;
mat4 scale;
};