#include <GL/gl.h>

#include <GL/glu.h>

#include <GL/glut.h>

#include <stdlib.h>

#include <stdio.h>

/* Create checkerboard texture */

#define checkImageWidth 128

#define checkImageHeight 128

static GLubyte checkImage[checkImageHeight][checkImageWidth][4];

static GLuint texName;

void makeCheckImage(void)

{

int i, j, c;

for (i = 0; i < checkImageHeight; i++) {

for (j = 0; j < checkImageWidth; j++) {

c = ((((i&0x8)==0)^((j&0x8)==0)))*255;

checkImage[i][j][0] = (GLubyte) c;

checkImage[i][j][1] = (GLubyte) c;

checkImage[i][j][2] = (GLubyte) c;

checkImage[i][j][3] = (GLubyte) 255;

}

}

}

void init(void)

{

GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 1.0 };

GLfloat mat_shininess[] = { 50.0 };

glClearColor (0.0, 0.0, 0.0, 0.0);

glShadeModel(GL_FLAT);

glEnable(GL_DEPTH_TEST);

glDepthFunc(GL_LEQUAL);

/* texture stuff */

makeCheckImage();

glPixelStorei(GL_UNPACK_ALIGNMENT, 1);

glGenTextures(1, &texName);

glBindTexture(GL_TEXTURE_2D, texName);

glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);

glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);

glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER,

GL_NEAREST);

glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,

GL_NEAREST);

glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, checkImageWidth,

checkImageHeight, 0, GL_RGBA, GL_UNSIGNED_BYTE,

checkImage);

/* lighting stuff */

glShadeModel (GL_SMOOTH);

glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, mat_specular);

glMaterialfv(GL_FRONT_AND_BACK, GL_SHININESS, mat_shininess);

glEnable(GL_LIGHTING);

glEnable(GL_LIGHT0);

}

void display(void)

{

GLfloat mat_red[] = {1.0, 0.0, 0.0, 0.0};

GLfloat mat_green[] = {0.0, 1.0, 0.0, 0.0};

GLfloat mat_blue[] = {0.0, 0.0, 1.0, 0.0};

GLfloat mat_black[] = {0.0, 0.0, 0.0, 0.0};

GLfloat light_position[] = {10.0, 10.0, 10.0, 0.0};

/* this will be your shadow matrix. You need to specify what this contains.

* OpenGL has a funky ordering for rows and columns

* use this ordering for rows and columns

*/

GLfloat m[16];

m[0]= 1; m[4]= 0; m[8] = 0; m[12]= 0;

m[1]= 0; m[5]= 1; m[9] = 0; m[13]= 0;

m[2]= 0; m[6]= 0; m[10]= 0; m[14]= 0;

m[3]= 0; m[7]= 0; m[11]= 0; m[15]= 1;

glLoadIdentity();

gluLookAt(10,0,5, 0,0,0, 0,0,1);

glLightfv(GL_LIGHT0, GL_POSITION, light_position);

glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

/* draw checkered floor */

glEnable(GL_TEXTURE_2D);

glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL);

glBindTexture(GL_TEXTURE_2D, texName);

glBegin(GL_QUADS);

/* z=-0.01 so that the floor doesn't overlap your shadows */

glTexCoord2f(0.0, 0.0); glVertex3f(-4.0, -4.0, -0.01);

glTexCoord2f(0.0, 1.0); glVertex3f(-4.0, 4.0, -0.01);

glTexCoord2f(1.0, 1.0); glVertex3f( 4.0, 4.0, -0.01);

glTexCoord2f(1.0, 0.0); glVertex3f( 4.0, -4.0, -0.01);

glEnd();

glFlush();

glDisable(GL_TEXTURE_2D);

/* draw cubes */

/* scale translate and draw blue cube */

glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, mat_blue);

glPushMatrix();

glTranslatef(2.5, 2.5, 0); // translate cube front and right.

glScalef(0.5, 0.5, 3); // scale to be narrow and tall

glTranslatef(0,0,0.5); // translate unit cube to surface

glutSolidCube(1); // draw unit cube

glPopMatrix();

/* scale rotate and draw green cube */

glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, mat_green);

glPushMatrix();

glTranslatef(0, -3, 0.5); // translate to left side and up so that it is on the surface

glRotatef(90, 1, 0, 0); // rotate to its side

glScalef(0.5, 0.5, 3); // scale to be narrow and tall

glutSolidCube(1); // draw unit cube

glPopMatrix();

/* apply a matrix 'm' to a cone w/o scaling, rotation, or projection */

/* the matrix is wrong, so don't expect this to work */

glDisable(GL_LIGHTING); // so that OpenGL doesn't shade your shadows.

glColor3f(0.0, 0.0, 0.0); // shadow color

glPushMatrix();

glMultMatrixf(m); // apply transform of matrix m

glutSolidCube(1); // draw unit cube

glPopMatrix();

glEnable(GL_LIGHTING); // enable lighting for future calls to display()

glFlush();

}

void reshape(int w, int h)

{

glViewport(0, 0, (GLsizei) w, (GLsizei) h);

glMatrixMode(GL_PROJECTION);

glLoadIdentity();

gluPerspective(60.0, (GLfloat) w/(GLfloat) h, 1.0, 30.0);

glMatrixMode(GL_MODELVIEW);

glLoadIdentity();

}

void keyboard (unsigned char key, int x, int y)

{

switch (key) {

case 27:

exit(0);

break;

default:

break;

}

}

int main(int argc, char** argv)

{

glutInit(&argc, argv);

glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);

glutInitWindowSize(500, 500);

glutInitWindowPosition(100, 100);

glutCreateWindow(argv[0]);

init();

glutDisplayFunc(display);

glutReshapeFunc(reshape);

glutKeyboardFunc(keyboard);

glutMainLoop();

return 0;

}