/* Copyright (c) Mark J. Kilgard, 1997. */
/* This program is freely distributable without licensing fees and is provided without guarantee or warrantee expressed or implied. This program is -not- in the public domain. */
/* This program was requested by Patrick Earl; hopefully someone else will write the equivalent Direct3D immediate mode program. */
#include <GL/glut.h>
GLfloat light_diffuse[] = {1.0, 0.0, 0.0, 1.0}; /* Red diffuse light. */ GLfloat light_position[] = {1.0, 1.0, 1.0, 0.0}; /* Infinite light location. */
GLfloat n[6][3] = { /* Normals for the 6 faces of a cube. */ {-1.0, 0.0, 0.0}, {0.0, 1.0, 0.0}, {1.0, 0.0, 0.0}, {0.0, -1.0, 0.0}, {0.0, 0.0, 1.0}, {0.0, 0.0, -1.0} };
GLint faces[6][4] = { /* Vertex indices for the 6 faces of a cube. */ {0, 1, 2, 3}, {3, 2, 6, 7}, {7, 6, 5, 4}, {4, 5, 1, 0}, {5, 6, 2, 1}, {7, 4, 0, 3} };
GLfloat v[8][3]; /* Will be filled in with X,Y,Z vertexes. */
void drawBox(void) { int i;
for (i = 0; i <6 ; i++) { glBegin(GL_QUADS); glNormal3fv(&n[i][0]); glVertex3fv(v[faces[i][0]]); glVertex3fv(v[faces[i][1]]); glVertex3fv(v[faces[i][2]]); glVertex3fv(&v[faces[i][3]][0]); glEnd(); } }
void display(void) { glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); drawBox(); glutSwapBuffers(); }
void init(void) { /* Setup cube vertex data. */ v[0][0] = v[1][0] = v[2][0] = v[3][0] = -1; v[4][0] = v[5][0] = v[6][0] = v[7][0] = 1; v[0][1] = v[1][1] = v[4][1] = v[5][1] = -1; v[2][1] = v[3][1] = v[6][1] = v[7][1] = 1; v[0][2] = v[3][2] = v[4][2] = v[7][2] = 1; v[1][2] = v[2][2] = v[5][2] = v[6][2] = -1;
/* Enable a single OpenGL light. */ glLightfv(GL_LIGHT0, GL_DIFFUSE, light_diffuse); glLightfv(GL_LIGHT0, GL_POSITION, light_position); glEnable(GL_LIGHT0); glEnable(GL_LIGHTING);
/* Use depth buffering for hidden surface elimination. */ glEnable(GL_DEPTH_TEST);
/* Setup the view of the cube. */ glMatrixMode(GL_PROJECTION); gluPerspective( /* field of view in degree */ 40.0, /* aspect ratio */ 1.0, /* Z near */ 1.0, /* Z far */ 10.0); glMatrixMode(GL_MODELVIEW); gluLookAt(0.0, 0.0, 5.0, /* eye is at (0,0,5) */ 0.0, 0.0, 0.0, /* center is at (0,0,0) */ 0.0, 1.0, 0.); /* up is in positive Y direction */
/* Adjust cube position to be asthetic angle. */ glTranslatef(0.0, 0.0, -1.0); glRotatef(60, 1.0, 0.0, 0.0); glRotatef(-20, 0.0, 0.0, 1.0); }
int main(int argc, char **argv) { glutInit(&argc, argv); glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH); glutCreateWindow("red 3D lighted cube"); glutDisplayFunc(display); init(); glutMainLoop(); return 0; /* ANSI C requires main to return int. */ }
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