Moving a 3D object with a mouse in OpenGL - c++

Question

I have been trying to make a whale in OpenGL. We have been trying to move the whale using a mouse input. The problem we are facing is with the syntax as well as the logic. We understand that the whale we are making is in a 3 dimensional world whereas the mouse input in in 2D for x and y on the screen.
If someone can be very specific with the syntax of using mouse input relevant to our code, that'd be great!
#include <Windows.h>
#include <GL/gl.h>
#include <GL/glu.h>
#include <stdlib.h>
#include "glut.h"
#include <math.h>
GLUquadric *qobja;
float movez = 0;
#define W_SCREEN 1366
#define H_SCREEN 768
#define TERR_D 75
#define TERR_W 750
#define pi 3.14
int mou_x = 0, mou_y = 0;
float alpha = 0;
float fahad = 0;
GLfloat ctrlpoints[4][4][3] = {
{ { -1.5, -1.5, 4.0 },
{ -0.5, -1.5, 2.0 },
{ 0.5, -1.5, -1.0 },
{ 1.5, -1.5, 2.0 } },
{ { -1.5, -0.5, 1.0 },
{ -0.5, -0.5, 3.0 },
{ 0.5, -0.5, 0.0 },
{ 1.5, -0.5, -1.0 } },
{ { -1.5, -1.5, 4.0 },
{ -0.5, -1.5, 2.0 },
{ 0.5, -1.5, -1.0 },
{ 1.5, -1.5, 2.0 } },
{ { -1.5, 1.5, -2.0 },
{ -0.5, 1.5, -2.0 },
{ 0.5, 1.5, 0.0 },
{ 1.5, 1.5, -1.0 } }
};
float cam_xrot = 180, cam_yrot = 180, cam_zrot = 0;
GLfloat no_mat[] = { 0.0, 0.0, 0.0, 1.0 };
GLfloat mat_ambient[] = { 0.7, 0.7, 0.7, 1.0 };
GLfloat mat_ambient_color[] = { 0.8, 0.8, 0.2, 1.0 };
GLfloat mat_diffuse[] = { 0.1, 0.5, 0.8, 1.0 };
GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 1.0 };
GLfloat no_shininess[] = { 0.0 };
GLfloat low_shininess[] = { 5.0 };
GLfloat high_shininess[] = { 100.0 };
GLfloat mat_emission[] = { 0.3, 0.2, 0.2, 0.0 };
// Function Prototypes ////////////////////////////////////
void drawTerrain();
void drawAxes();
//drawing function decs
void draw_frust(float inner, float outer, float height, float m_z);
void cleanup();
void camera();
void pyramid();
void draw_closed_cyl(float a, float b, float c);
void draw_whale();
/* Initialize z-buffer, projection matrix, light source,
* and lighting model. Do not specify a material property here.
*/
void initLight(void)
{
GLfloat ambient[] = { 0.2, 0.2, 0.2, 1.0 };
GLfloat position[] = { 0.0, 0.0, 2.0, 1.0 };
GLfloat mat_diffuse[] = { 0.6, 0.6, 0.6, 1.0 };
GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 1.0 };
GLfloat mat_shininess[] = { 50.0 };
glEnable(GL_LIGHTING);
glEnable(GL_LIGHT0);
glLightfv(GL_LIGHT0, GL_AMBIENT, ambient);
glLightfv(GL_LIGHT0, GL_POSITION, position);
glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);
glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);
glMaterialfv(GL_FRONT, GL_SHININESS, mat_shininess);
}
void init(void)
{
glClearColor(0.0, 0.0, 0.0, 0.0);
glEnable(GL_DEPTH_TEST);
glMap2f(GL_MAP2_VERTEX_3, 0, 1, 3, 4,
0, 1, 12, 4, &ctrlpoints[0][0][0]);
glEnable(GL_MAP2_VERTEX_3);
glEnable(GL_AUTO_NORMAL);
glMapGrid2f(20, 0.0, 1.0, 20, 0.0, 1.0);
initLight();
}
///////////////////////////////////////////////////////////
void display(void)
{
glClearColor(1.0, 1.0, 1.0, 1.0);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
camera();
drawAxes();
qobja = gluNewQuadric();
gluQuadricNormals(qobja, GLU_SMOOTH);
glPushMatrix();
glTranslatef(0, 0, movez);
draw_whale();
glPopMatrix();
}
void draw_whale()
{
glPushMatrix();
glTranslatef(0, 2, 90);
glRotatef(180, 0.0, 0.0, 1.0);
glScalef(1, 1, 2);
glEvalMesh2(GL_FILL, 0, 25, 0, 25);
glPopMatrix();
glPushMatrix();
float count = 5;
float a = 5;
for (float i = 0; i <= 16; i = i + 1)
{
draw_frust(a*sqrt(i), a*sqrt((i + 1)), 2, count * 2);
count++;
alpha = i + 1;
}
//a few smooth runs
for (int j = 0; j < 3; j++)
{
draw_frust(a*sqrt(alpha), a*sqrt(alpha), 2, count * 2);
count++;
}
float co = count;
for (float i = 17; i >= 3; i = i - 1)
{
draw_frust(a*sqrt(i), a*sqrt(i - 1), 2, co * 2);
co++;
fahad = a*sqrt(i - 1);
}
draw_frust(7.07, 5, 2, co * 2);
co++;
draw_frust(5, 3, 2, co * 2);
co++;
draw_frust(3, 1, 2, co * 2);
glPushMatrix();
//fin left
glPushMatrix();
glTranslatef(-25.5, 10, 25);
glRotatef(100, 1, 0, 0);
glRotatef(135, 0, 1, 0);
glRotatef(45, 0, 0, 1);
glScalef(1, 6, 1);
draw_closed_cyl(0, 0, 0);
glPopMatrix();
//fin right
glPushMatrix();
glTranslatef(25.5, 10, 25);
glRotatef(100, 1, 0, 0);
glRotatef(-135, 0, 1, 0);
glRotatef(-45, 0, 0, 1);
glScalef(1, 6, 1);
draw_closed_cyl(0, 0, 0);
glPopMatrix();
glPopMatrix();
glutSwapBuffers();
}
void draw_frust(float inner, float outer, float height, float m_z)
{
qobja = gluNewQuadric();
gluQuadricNormals(qobja, GLU_SMOOTH);
glPushMatrix();
glTranslatef(0, 0, m_z);
gluDisk(qobja, 0.0, inner, 200, 20);
gluCylinder(qobja, inner, outer, height, 200, 200);
glPopMatrix();
}
void draw_closed_cyl(float a, float b, float c)
{
qobja = gluNewQuadric();
gluQuadricNormals(qobja, GLU_SMOOTH);
glPushMatrix();
glTranslatef(a, b + 2, c);
glRotatef(120, 0, 0, 1);
gluCylinder(qobja, 3.0, 3.0, 2.0, 20, 20);
gluDisk(qobja, 0, 3.0, 20, 20);
glTranslatef(0, 0, 2.0);
gluDisk(qobja, 0, 3.0, 20, 20);
glPopMatrix();
}
void drawTerrain(){
GLfloat color[] = { 0.2, 0.8, 0.2 };
glMaterialfv(GL_FRONT, GL_AMBIENT, color);
glColor3f(0.2, 0.8, 0.2); // this line is not needed when lighting in enabled
glPushMatrix();
glTranslatef(-TERR_W / 2, 0.0, -TERR_D / 2);
glBegin(GL_POLYGON);
glVertex3f(0, 0, 0);
glVertex3f(TERR_W, 0, 0);
glVertex3f(TERR_W, 0, TERR_D);
glVertex3f(0, 0, TERR_D);
glVertex3f(0, 0, 0);
glEnd();
glPopMatrix();
}
void drawAxes(){
glColor3d(1, 0, 0);
glBegin(GL_LINES);
glVertex3f(0, 0, 0);
glVertex3f(3, 0, 0);
glEnd();
glColor3d(0, 1, 0);
glBegin(GL_LINES);
glVertex3f(0, 0, 0);
glVertex3f(0, 3, 0);
glEnd();
glColor3d(0, 0, 1);
glBegin(GL_LINES);
glVertex3f(0, 0, 0);
glVertex3f(0, 0, 3);
glEnd();
}
///////////////////////////////////////////////////////////
void reshape(int w, int h)
{
glViewport(0, 0, (GLsizei)w, (GLsizei)h);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(1.5*60.0, (GLfloat)w / (GLfloat)h, 1, 1.5*120.0);
glMatrixMode(GL_MODELVIEW);
camera();
}
///////////////////////////////////////////////////////////
void camera(){
glLoadIdentity();
glTranslatef(0, 0, -110);
glRotatef(cam_xrot, 1, 0, 0);
glRotatef(cam_yrot, 0, 1, 0);
glRotatef(cam_zrot, 0, 0, 1);
}
///////////////////////////////////////////////////////////
void keyboard(unsigned char key, int x, int y)
{
// Camera controls - Rotation along principle axis
switch (key) {
case 'n':
if (movez <= -100)
movez = movez + 100;
else
movez = movez - 3;
break;
case 'q':
cam_xrot += 10;
if (cam_xrot >360) cam_xrot -= 360;
break;
case 'z':
cam_xrot -= 10;
if (cam_xrot < -360) cam_xrot += 360;
break;
case 'a':
cam_yrot += 10;
if (cam_yrot >360) cam_yrot -= 360;
break;
case 'd':
cam_yrot -= 10;
if (cam_yrot < -360) cam_yrot += 360;
break;
case 'w':
cam_zrot += 10;
if (cam_zrot >360) cam_zrot -= 360;
break;
case 'x':
cam_zrot -= 10;
if (cam_zrot < -360) cam_zrot += 360;
break;
case 27:
cleanup();
exit(0);
break;
default:
break;
}
glutPostRedisplay();
}
///////////////////////////////////////////////////////////
void cleanup() // call once when you exit program
{
}
///////////////////////////////////////////////////////////
int main(int argc, char** argv)
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB);
glutInitWindowSize(W_SCREEN, H_SCREEN);
glutInitWindowPosition(0, 0);
glutCreateWindow(argv[0]);
init();
glutDisplayFunc(display);
glutReshapeFunc(reshape);
glutTimerFunc(25, update, 0);
glutKeyboardFunc(keyboard);
glutMainLoop();
return 0;
}