Program 5: Write a program to create a scene using OpenGL illumination functions.

PROGRAM 5: LIGHT

·         Header File

·         Render func

·         Handle resize

·         Display

·         Timer

·         Main func

1.      Header File.(gl/glut.h , math.h, windows.h) // REFER 2d 
       link:http://simplifiedopengl.blogspot.in/2016/08/program-3-write-program-to-implement-2d.html

2.      Initialise rendering function for the 2d object// REFER 2d and include the below mentioned effects for 3d

glEnable(GL_COLOR_MATERIAL);

            glEnable(GL_LIGHTING); //Enable lighting

            glEnable(GL_LIGHT0); //Enable light #0

            glEnable(GL_NORMALIZE); //Automatically normalize normals

3.      Create Handle Resize // REFER 2d

4.       Display Function // REFER 2d

void drawScene()

{

    glClearColor(0.0f, 0.0f, 1.0f, 0.0f);//dark blue

    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);

    glMatrixMode(GL_MODELVIEW);

    glLoadIdentity();

    glRotatef(_angle,0.0f,0.0f,1.0f); //rotate object by 30 degree with respect to y-axis

    glTranslatef(0.0f, 0.0f, -10.0f);

GLfloat ambientColor[] = {0.2f, 0.2f, 0.2f, 1.0f}; //Color (0.2, 0.2, 0.2)

       GLfloat light_ambient[] = {1.0, 1.0,1.0,1.0};//producing the color

      glLightModelfv(GL_LIGHT_MODEL_AMBIENT, ambientColor);

      GLfloat lightPos0[] = {0.0f, 0.0f, 1.0f, 0.0f}; //Positioned at (4, 0, 8)

      glLightfv(GL_LIGHT0, GL_DIFFUSE, light_ambient);

      glLightfv(GL_LIGHT0, GL_POSITION, lightPos0);

    //************************

      //OBJ

//Right face (x = 1.0f), Left face (x = -1.0f), Back face (z = -1.0f), Front face  (z = 1.0f), Bottom face (y = -1.0f), top face(z=1.0f)

glutSwapBuffers();

}

5.      Timer

6.      Main Function

SAMPLE PROGRAM

#include <iostream>

#include <stdlib.h>

#include <GL/glut.h>

using namespace std;

//Initializes 3D rendering

void initRendering() {

            glEnable(GL_DEPTH_TEST);

            glEnable(GL_COLOR_MATERIAL);

            glEnable(GL_LIGHTING); //Enable lighting

            glEnable(GL_LIGHT0); //Enable light #0

            glEnable(GL_NORMALIZE); //Automatically normalize normals

}

void handleResize(int w, int h) {

            glViewport(0, 0, w, h);

            glMatrixMode(GL_PROJECTION);

            glLoadIdentity();

            gluPerspective(45.0, (double)w / (double)h, 1.0, 200.0);

}

float _angle = 0.0f;

//Draws the 3D scene

void drawScene() {

            glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

            glMatrixMode(GL_MODELVIEW);

            glLoadIdentity();

            glTranslatef(0.0f, 0.0f, -5.0f);

            //Add ambient light

            GLfloat ambientColor[] = {0.2f, 0.2f, 0.2f, 1.0f}; //Color (0.2, 0.2, 0.2)

             GLfloat light_ambient[] = {1.0, 1.0,1.0,1.0};//producing the color

            glLightModelfv(GL_LIGHT_MODEL_AMBIENT, ambientColor);

            GLfloat lightPos0[] = {0.0f, 0.0f, 1.0f, 0.0f}; //Positioned at (4, 0, 8)

            glLightfv(GL_LIGHT0, GL_DIFFUSE, light_ambient);

            glLightfv(GL_LIGHT0, GL_POSITION, lightPos0);

            glRotatef(_angle, 1.0f,0.0f, 0.0f);

    glColor4f(0.0f, 1.0f, 1.0f, 1.0f);//light blue

    glBegin(GL_QUADS);                // Begin drawing the color cube with 6 quads

      // Top face (y = 1.0f)

      // Define vertices in counter-clockwise (CCW) order with normal pointing out

      glColor3f(0.0f, 1.0f, 0.0f);     // Green

      glVertex3f( 1.0f, 1.0f, -1.0f);

      glVertex3f(-1.0f, 1.0f, -1.0f);

      glVertex3f(-1.0f, 1.0f,  1.0f);

      glVertex3f( 1.0f, 1.0f,  1.0f);

      // Bottom face (y = -1.0f)

    glColor3f(1.0f, 1.0f, 0.0f);     // Yellow

      glVertex3f( 1.0f, -1.0f,  1.0f);

      glVertex3f(-1.0f, -1.0f,  1.0f);

      glVertex3f(-1.0f, -1.0f, -1.0f);

      glVertex3f( 1.0f, -1.0f, -1.0f);

      // Front face  (z = 1.0f)

      glColor3f(1.0f, 0.0f, 0.0f);     // Red

      glVertex3f( 1.0f,  1.0f, 1.0f);

      glVertex3f(-1.0f,  1.0f, 1.0f);

      glVertex3f(-1.0f, -1.0f, 1.0f);

      glVertex3f( 1.0f, -1.0f, 1.0f);

      // Back face (z = -1.0f)

      glColor3f(1.0f, 1.0f, 1.0f);     // Yellow

      glVertex3f( 1.0f, -1.0f, -1.0f);

      glVertex3f(-1.0f, -1.0f, -1.0f);

      glVertex3f(-1.0f,  1.0f, -1.0f);

      glVertex3f( 1.0f,  1.0f, -1.0f);

      // Left face (x = -1.0f)

      glColor3f(0.0f, 0.0f, 1.0f);     // Blue

      glVertex3f(-1.0f,  1.0f,  1.0f);

      glVertex3f(-1.0f,  1.0f, -1.0f);

      glVertex3f(-1.0f, -1.0f, -1.0f);

      glVertex3f(-1.0f, -1.0f,  1.0f);

      // Right face (x = 1.0f)

      glColor3f(1.0f, 0.0f, 1.0f);     // Magenta

      glVertex3f(1.0f,  1.0f, -1.0f);

      glVertex3f(1.0f,  1.0f,  1.0f);

      glVertex3f(1.0f, -1.0f,  1.0f);

      glVertex3f(1.0f, -1.0f, -1.0f);

    glEnd();  // End of drawing color-cube

            glutSwapBuffers();

            glFlush();

}

void update(int value) {

            _angle += 1.5f;

            if (_angle > 360) {

                        _angle -= 360;

            }

            glutPostRedisplay();

            glutTimerFunc(25, update,0);

}

int main(int argc, char** argv) {

            //Initialize GLUT

            glutInit(&argc, argv);

            glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);

            glutInitWindowSize(400, 400);

            glutCreateWindow("Lighting");

            initRendering();

            glutDisplayFunc(drawScene);

            glutReshapeFunc(handleResize);

            glutTimerFunc(25, update, 0); //Add a timer

            glutMainLoop();

            return 0;

}

Program 4: Write a program to implement 3D Geometric Transformations.

PROGRAM 4: 3D

·         Header File

·         Render func

·         Handle resize

·         Display

·         Timer

·         Main func

1.      Header File.(gl/glut.h , math.h, windows.h) // REFER 2d link: http://simplifiedopengl.blogspot.in/2016/08/program-3-write-program-to-implement-2d.html

2.      Initialise rendering function for the 2d object// REFER 2d

3.      Create Handle Resize // REFER 2d

4.      Display Function // REFER 2d

void drawScene()

{

    glClearColor(0.0f, 0.0f, 1.0f, 0.0f);//dark blue

    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);

    glMatrixMode(GL_MODELVIEW);

    glLoadIdentity();

    glRotatef(_angle,0.0f,0.0f,1.0f); //rotate object by 30 degree with respect to y-axis

    glTranslatef(0.0f, 0.0f, -10.0f);

    //************************

      //OBJ

//Right face (x = 1.0f), Left face (x = -1.0f), Back face (z = -1.0f), Front face  (z = 1.0f), Bottom face (y = -1.0f), top face(z=1.0f)

glutSwapBuffers();

}

5.      Timer

6.      Main Function

SAMPLE PROGRAM: 4 3D

//header file same as all

GLfloat angleCube = 0.0f;     // Rotational angle for cube [NEW]

void initRendering() {

   glEnable(GL_DEPTH_TEST);   // Enable depth testing for z-culling

}

void handleResize(int w,int h)

{

glViewport(0,0,w,h);

glMatrixMode(GL_PROJECTION);

glLoadIdentity();

gluPerspective(45.0,(double)w/(double)h,1.0,200.0);

}

void display() {

   glClearColor(0.0f, 0.0f, 0.0f, 1.0f); // Set background color to black and opaque

   glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // Clear color and depth buffers

   glMatrixMode(GL_MODELVIEW);     // To operate on model-view matrix

   glLoadIdentity();                 // Reset the model-view matrix

   glTranslatef(-1.5f, 0.0f, -6.0f);  // Move right and into the screen

   glRotatef(angleCube, 0.0f, 1.0f, 1.0f);  // Rotate about (1,1,1)-axis [NEW]

   glBegin(GL_QUADS);                // Begin drawing the color cube with 6 quads

      glColor3f(0.0f, 1.0f, 0.0f);     // Green

      glVertex3f( 1.0f, 1.0f, -1.0f);

      glVertex3f(-1.0f, 1.0f, -1.0f);

      glVertex3f(-1.0f, 1.0f,  1.0f);

      glVertex3f( 1.0f, 1.0f,  1.0f);

      // Bottom face (y = -1.0f)

    glColor3f(1.0f, 1.0f, 0.0f);     // Yellow

      glVertex3f( 1.0f, -1.0f,  1.0f);

      glVertex3f(-1.0f, -1.0f,  1.0f);

      glVertex3f(-1.0f, -1.0f, -1.0f);

      glVertex3f( 1.0f, -1.0f, -1.0f);

      // Front face  (z = 1.0f)

      glColor3f(1.0f, 0.0f, 0.0f);     // Red

      glVertex3f( 1.0f,  1.0f, 1.0f);

      glVertex3f(-1.0f,  1.0f, 1.0f);

      glVertex3f(-1.0f, -1.0f, 1.0f);

      glVertex3f( 1.0f, -1.0f, 1.0f);

      // Back face (z = -1.0f)

      glColor3f(1.0f, 1.0f, 0.0f);     // Yellow

      glVertex3f( 1.0f, -1.0f, -1.0f);

      glVertex3f(-1.0f, -1.0f, -1.0f);

      glVertex3f(-1.0f,  1.0f, -1.0f);

      glVertex3f( 1.0f,  1.0f, -1.0f);

      // Left face (x = -1.0f)

      glColor3f(0.0f, 0.0f, 1.0f);     // Blue

      glVertex3f(-1.0f,  1.0f,  1.0f);

      glVertex3f(-1.0f,  1.0f, -1.0f);

      glVertex3f(-1.0f, -1.0f, -1.0f);

      glVertex3f(-1.0f, -1.0f,  1.0f);

      // Right face (x = 1.0f)

      glColor3f(1.0f, 0.0f, 1.0f);     // Magenta

      glVertex3f(1.0f,  1.0f, -1.0f);

      glVertex3f(1.0f,  1.0f,  1.0f);

      glVertex3f(1.0f, -1.0f,  1.0f);

      glVertex3f(1.0f, -1.0f, -1.0f);

   glEnd();  // End of drawing color-cube

    glutSwapBuffers();  // Swap the front and back frame buffers (double buffering)

    angleCube -= 0.15f;

}

void update(int value) {

    angleCube+=2.0f;

    if(angleCube>360.f)

    {

    angleCube-=360;

    }

    glutPostRedisplay();

    glutTimerFunc(25,update,0);

}

int main(int argc, char** argv) {

   glutInit(&argc, argv);            // Initialize GLUT

   glutInitDisplayMode(GLUT_DOUBLE); // Enable double buffered mode

   glutInitWindowSize(640, 480);   // Set the window's initial width & height

   glutInitWindowPosition(50, 50); // Position the window's initial top-left corner

   glutCreateWindow("PROGRAM4");          // Create window with the given title

   glutDisplayFunc(display);       // Register callback handler for window re-paint event

   glutReshapeFunc(handleResize);       // Register callback handler for window re-size event

   initRendering();                       // Our own OpenGL initialization

   glutTimerFunc(0, update, 0);     // First timer call immediately [NEW]

   glutMainLoop();                 // Enter the infinite event-processing loop

   return 0;

}

Program 3: Write a program to implement 2D Geometric Transformations.

PROGRAM 3: 2D transformations

·         Header File

·         Render func

·         Handle resize

·         Display

·         Timer

·         Main func

1.      Header File.(gl/glut.h , math.h, windows.h)

2.      Initialise rendering function for the 2d object

void initRendering()

{         

glEnable(GL_DEPTH_TEST);

}

3.      Create Handle Resize

void handleResize(int w,int h)

{

glViewport(0,0,w,h);

glMatrixMode(GL_PROJECTION);

glLoadIdentity();

gluPerspective(45.0,(double)w/(double)h,1.0,200.0);

}

4.      Display Function

void drawScene()

{

    glClearColor(0.0f, 0.0f, 1.0f, 0.0f);//dark blue

    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);

    glMatrixMode(GL_MODELVIEW);

    glLoadIdentity();

    glRotatef(_angle,0.0f,0.0f,1.0f); //rotate object by 30 degree with respect to y-axis

    glTranslatef(0.0f, 0.0f, -10.0f);

    //************************

    glPushMatrix();

    glScalef(2,2,2);

    //OBJ

      glPopMatrix();

    glutSwapBuffers();

}

5.      Timer

void update(int value)

{

       _angle+=2.0f;

      if(_angle>360.f)

      {

                  _angle-=360;

      }

    glutPostRedisplay();

    glutTimerFunc(25,update,0);

}

6.      Main Function

int main(int argc,char**argv)

{

    glutInit(&argc,argv);

    glutInitDisplayMode(GLUT_DOUBLE|GLUT_RGB|GLUT_DEPTH);

    glutInitWindowSize(600,600);

    glutCreateWindow("rotate");

    initRendering();

    glutDisplayFunc(drawScene);

    glutReshapeFunc(handleResize);

    glutTimerFunc(25,update,0);

    glutMainLoop();

    return 0;

}

SAMPLE PROGRAM:PROGRAM 3

//header file and include math.h as well

#include<math.h>

float _angle=45.0;

void initRendering()

{

glEnable(GL_DEPTH_TEST);

}

void handleResize(int w,int h)

{

glViewport(0,0,w,h);

glMatrixMode(GL_PROJECTION);

glLoadIdentity();

gluPerspective(45.0,(double)w/(double)h,1.0,200.0);

}

void drawScene()

{

    glClearColor(0.0f, 0.0f, 1.0f, 0.0f);//dark blue

    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);

    glMatrixMode(GL_MODELVIEW);

    glLoadIdentity();

    glRotatef(_angle,0.0f,0.0f,1.0f); //rotate object by 30 degree with respect to y-axis

    glTranslatef(0.0f, 0.0f, -10.0f);

    //************************

    glPushMatrix();

    glScalef(2,2,2);

    //OBJ

    glPopMatrix();

    glutSwapBuffers();

}

void update(int value)

{

    _angle+=2.0f;

    if(_angle>360.f)

    {

    _angle-=360;

    }

    glutPostRedisplay();

    glutTimerFunc(25,update,0);

}

int main(int argc,char**argv)

{

    glutInit(&argc,argv);

    glutInitDisplayMode(GLUT_DOUBLE|GLUT_RGB|GLUT_DEPTH);

    glutInitWindowSize(600,600);

    glutCreateWindow("rotate");

    initRendering();

    glutDisplayFunc(drawScene);

    glutReshapeFunc(handleResize);

    glutTimerFunc(25,update,0);

    glutMainLoop();

    return 0;

}

Program 2: Write a program to draw objects using Line-Attribute, Fill-Area Attribute, Color functions of OpenGL.

PROGRAM 2: (Line, fill, color attributes)

1.      Header File : same as the previous prog. link: http://simplifiedopengl.blogspot.in/2016/08/simplified-output-primitive-function.html

2.      Display Function

//LINE ATTRIBUTES: line colour, stipple, width.

    GLint factor=1;

    GLushort pattern=0x00ff;

    glEnable(GL_LINE_STIPPLE);

    glLineStipple(factor,pattern);

//then create the object.

glDisable(GL_LINE_STIPPLE);

//COLOR FUNCTION: gradient color and solid color.

Gradient: Give, glColor3f(0.0,0.0,1.0); before every vertex;

Solid: glColor3f(0.0,0.0,1.0); before the object creation.

//POLYGON FILL

//declare: GLubyte mask[128]; outside the display function

GLubyte Lines[] = {

    0x00, 0x00, 0x00, 0x00,

    0xff, 0xff, 0xff, 0xff,

    };

    glEnable(GL_POLYGON_STIPPLE);

     glPolygonStipple(Lines);

//draw polygon

    glDisable(GL_POLYGON_STIPPLE);

3.      Main function same as the firs program.

SAMPLE: PROGRAM 2

//header file: windows and glut

GLubyte mask[128];

void display()

{

    glClearColor(0.0,0.0,0.0,0.0);

    glClear(GL_COLOR_BUFFER_BIT);

    //LINE ATRRIBUTES:

    GLint factor=1;

    GLushort pattern=0x00ff;

    glEnable(GL_LINE_STIPPLE);

    glLineStipple(factor,pattern);

    glColor3f(1.0,1.0,1.0); //solid line color

    glBegin(GL_LINES);

    glVertex2f(0.0,0.0);

    glVertex2f(0.40,0.0);

    glLineWidth(10.0f);// line attribute

    glEnd();

    glDisable(GL_LINE_STIPPLE);

    //COLOR FUNCTION: gradient

    glBegin(GL_LINES);

    glColor3f(0.0,0.0,1.0); //blue

    glVertex2f(0.0,0.10);

    glColor3f(1.0,1.0,0.0);//yellow

    glVertex2f(0.40,0.10);

    glEnd();

    //Fill area:POLYGON FILL

    GLubyte Lines[] = {

    0x00, 0x00, 0x00, 0x00,

    0xff, 0xff, 0xff, 0xff,

    };

    glEnable(GL_POLYGON_STIPPLE);

     glPolygonStipple(Lines);

    glColor4f(1.0f, 0.0f, 0.0f, 0.0f);//red

    glBegin(GL_POLYGON);

    glVertex2f(-0.44,0.45);

    glVertex2f(-0.57,0.45);

    glVertex2f(-0.65,0.10);

    glVertex2f(-0.90,-0.60);

    glVertex2f(-0.10,-0.60);

    glEnd();

    glDisable(GL_POLYGON_STIPPLE);

    glFlush();

}

int main(int argc,char** argv)

{

    glutInit(&argc, argv);

    glutCreateWindow("Prog");

    glutInitWindowSize(320,320);

    glutDisplayFunc(display);

    glutMainLoop();

    return 0;

}