progs/samples/fog.c

   1 /*
   2  * Copyright (c) 1991, 1992, 1993 Silicon Graphics, Inc.
   3  *
   4  * Permission to use, copy, modify, distribute, and sell this software and
   5  * its documentation for any purpose is hereby granted without fee, provided
   6  * that (i) the above copyright notices and this permission notice appear in
   7  * all copies of the software and related documentation, and (ii) the name of
   8  * Silicon Graphics may not be used in any advertising or
   9  * publicity relating to the software without the specific, prior written
  10  * permission of Silicon Graphics.
  11  *
  12  * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF
  13  * ANY KIND,
  14  * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
  15  * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
  16  *
  17  * IN NO EVENT SHALL SILICON GRAPHICS BE LIABLE FOR
  18  * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
  19  * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
  20  * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
  21  * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
  22  * OF THIS SOFTWARE.
  23  */
  24
  25 #include <stdio.h>
  26 #include <string.h>
  27 #include <stdlib.h>
  28 #include <GL/glut.h>
  29
  30 GLenum rgb, doubleBuffer;
  31
  32 #include "tkmap.c"
  33
  34 double plane[4] = {
  35     1.0, 0.0, -1.0, 0.0
  36 };
  37 float rotX = 5.0, rotY = -5.0, zTranslate = -65.0;
  38 float fogDensity = 0.02;
  39 GLint cubeList = 1;
  40
  41 float scp[18][3] = {
  42     {
  43         1.000000, 0.000000, 0.000000
  44     },
  45     {
  46         1.000000, 0.000000, 5.000000
  47     },
  48     {
  49         0.707107, 0.707107, 0.000000
  50     },
  51     {
  52         0.707107, 0.707107, 5.000000
  53     },
  54     {
  55         0.000000, 1.000000, 0.000000
  56     },
  57     {
  58         0.000000, 1.000000, 5.000000
  59     },
  60     {
  61         -0.707107, 0.707107, 0.000000
  62     },
  63     {
  64         -0.707107, 0.707107, 5.000000
  65     },
  66     {
  67         -1.000000, 0.000000, 0.000000
  68     },
  69     {
  70         -1.000000, 0.000000, 5.000000
  71     },
  72     {
  73         -0.707107, -0.707107, 0.000000
  74     },
  75     {
  76         -0.707107, -0.707107, 5.000000
  77     },
  78     {
  79         0.000000, -1.000000, 0.000000
  80     },
  81     {
  82         0.000000, -1.000000, 5.000000
  83     },
  84     {
  85         0.707107, -0.707107, 0.000000
  86     },
  87     {
  88         0.707107, -0.707107, 5.000000
  89     },
  90     {
  91         1.000000, 0.000000, 0.000000
  92     },
  93     {
  94         1.000000, 0.000000, 5.000000
  95     },
  96 };
  97
  98
  99 static void Build_lists(void)
 100 {
 101
 102     glNewList(cubeList, GL_COMPILE);
 103         glBegin(GL_TRIANGLE_STRIP);
 104            glNormal3fv(scp[0]); glVertex3fv(scp[0]);
 105            glNormal3fv(scp[0]); glVertex3fv(scp[1]);
 106            glNormal3fv(scp[2]); glVertex3fv(scp[2]);
 107            glNormal3fv(scp[2]); glVertex3fv(scp[3]);
 108            glNormal3fv(scp[4]); glVertex3fv(scp[4]);
 109            glNormal3fv(scp[4]); glVertex3fv(scp[5]);
 110            glNormal3fv(scp[6]); glVertex3fv(scp[6]);
 111            glNormal3fv(scp[6]); glVertex3fv(scp[7]);
 112            glNormal3fv(scp[8]); glVertex3fv(scp[8]);
 113            glNormal3fv(scp[8]); glVertex3fv(scp[9]);
 114            glNormal3fv(scp[10]); glVertex3fv(scp[10]);
 115            glNormal3fv(scp[10]); glVertex3fv(scp[11]);
 116            glNormal3fv(scp[12]); glVertex3fv(scp[12]);
 117            glNormal3fv(scp[12]); glVertex3fv(scp[13]);
 118            glNormal3fv(scp[14]); glVertex3fv(scp[14]);
 119            glNormal3fv(scp[14]); glVertex3fv(scp[15]);
 120            glNormal3fv(scp[16]); glVertex3fv(scp[16]);
 121            glNormal3fv(scp[16]); glVertex3fv(scp[17]);
 122         glEnd();
 123     glEndList();
 124 }
 125
 126 static void Init(void)
 127 {
 128     static float ambient[] = {0.1, 0.1, 0.1, 1.0};
 129     static float diffuse[] = {1.0, 1.0, 1.0, 1.0};
 130     static float position[] = {90.0, 90.0, 0.0, 0.0};
 131     static float front_mat_shininess[] = {30.0};
 132     static float front_mat_specular[] = {0.0, 0.0, 0.0, 1.0};
 133     static float front_mat_diffuse[] = {0.0, 1.0, 0.0, 1.0};
 134     static float back_mat_shininess[] = {50.0};
 135     static float back_mat_specular[] = {0.0, 0.0, 1.0, 1.0};
 136     static float back_mat_diffuse[] = {1.0, 0.0, 0.0, 1.0};
 137     static float lmodel_ambient[] = {0.0, 0.0, 0.0, 1.0};
 138     static float fog_color[] = {0.8, 0.8, 0.8, 1.0};
 139
 140     glFrontFace(GL_CW);
 141
 142     glEnable(GL_DEPTH_TEST);
 143
 144     glLightfv(GL_LIGHT0, GL_AMBIENT, ambient);
 145     glLightfv(GL_LIGHT0, GL_DIFFUSE, diffuse);
 146     glLightfv(GL_LIGHT0, GL_POSITION, position);
 147     glLightModelfv(GL_LIGHT_MODEL_AMBIENT, lmodel_ambient);
 148     glLightModeli(GL_LIGHT_MODEL_TWO_SIDE, GL_TRUE);
 149     glEnable(GL_LIGHTING);
 150     glEnable(GL_LIGHT0);
 151
 152     glMaterialfv(GL_FRONT, GL_SHININESS, front_mat_shininess);
 153     glMaterialfv(GL_FRONT, GL_SPECULAR, front_mat_specular);
 154     glMaterialfv(GL_FRONT, GL_DIFFUSE, front_mat_diffuse);
 155     glMaterialfv(GL_BACK, GL_SHININESS, back_mat_shininess);
 156     glMaterialfv(GL_BACK, GL_SPECULAR, back_mat_specular);
 157     glMaterialfv(GL_BACK, GL_DIFFUSE, back_mat_diffuse);
 158
 159     glEnable(GL_FOG);
 160     glFogi(GL_FOG_MODE, GL_EXP);
 161     glFogf(GL_FOG_DENSITY, fogDensity);
 162     if (rgb) {
 163         glFogfv(GL_FOG_COLOR, fog_color);
 164         glClearColor(0.8, 0.8, 0.8, 1.0);
 165     } else {
 166         glFogi(GL_FOG_INDEX, 1<<5);
 167         SetFogRamp(5, 3);
 168         glClearIndex(128);
 169     }
 170
 171     Build_lists();
 172 }
 173
 174 static void Reshape(int width, int height)
 175 {
 176
 177     glViewport(0, 0, (GLint)width, (GLint)height);
 178
 179     glMatrixMode(GL_PROJECTION);
 180     glLoadIdentity();
 181     gluPerspective(45.0, 1.0, 1.0, 200.0);
 182     glMatrixMode(GL_MODELVIEW);
 183 }
 184
 185 static void Key2(int key, int x, int y)
 186 {
 187
 188     switch (key) {
 189       case GLUT_KEY_UP:
 190         rotX -= 5;
 191         break;
 192       case GLUT_KEY_DOWN:
 193         rotX += 5;
 194         break;
 195       case GLUT_KEY_LEFT:
 196         rotY -= 5;
 197         break;
 198       case GLUT_KEY_RIGHT:
 199         rotY += 5;
 200         break;
 201       default:
 202         return;
 203     }
 204
 205     glutPostRedisplay();
 206 }
 207
 208 static void Key(unsigned char key, int x, int y)
 209 {
 210
 211     switch (key) {
 212       case 27:
 213         exit(1);
 214       case 'D':
 215         if (rgb) {
 216             fogDensity *= 1.10;
 217             glFogf(GL_FOG_DENSITY, fogDensity);
 218         }
 219         break;
 220       case 'd':
 221         if (rgb) {
 222             fogDensity /= 1.10;
 223             glFogf(GL_FOG_DENSITY, fogDensity);
 224         }
 225         break;
 226       default:
 227         return;
 228     }
 229
 230     glutPostRedisplay();
 231 }
 232
 233 static void Draw(void)
 234 {
 235
 236     glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
 237
 238     glPushMatrix();
 239
 240     glTranslatef(0, 0, zTranslate);
 241     glRotatef(rotY, 0,1,0);
 242     glRotatef(rotX, 1,0,0);
 243     glScalef(1.0, 1.0, 10.0);
 244
 245     glCallList(cubeList);
 246
 247     glPopMatrix();
 248
 249     glFlush();
 250
 251     if (doubleBuffer) {
 252         glutSwapBuffers();
 253     }
 254 }
 255
 256 static GLenum Args(int argc, char **argv)
 257 {
 258     GLint i;
 259
 260     rgb = GL_TRUE;
 261     doubleBuffer = GL_TRUE;
 262
 263     for (i = 1; i < argc; i++) {
 264         if (strcmp(argv[i], "-ci") == 0) {
 265             rgb = GL_FALSE;
 266         } else if (strcmp(argv[i], "-rgb") == 0) {
 267             rgb = GL_TRUE;
 268         } else if (strcmp(argv[i], "-sb") == 0) {
 269             doubleBuffer = GL_FALSE;
 270         } else if (strcmp(argv[i], "-db") == 0) {
 271             doubleBuffer = GL_TRUE;
 272         } else {
 273             printf("%s (Bad option).\n", argv[i]);
 274             return GL_FALSE;
 275         }
 276     }
 277     return GL_TRUE;
 278 }
 279
 280 int main(int argc, char **argv)
 281 {
 282     GLenum type;
 283
 284     glutInit(&argc, argv);
 285
 286     if (Args(argc, argv) == GL_FALSE) {
 287         exit(1);
 288     }
 289
 290     glutInitWindowPosition(0, 0); glutInitWindowSize( 300, 300);
 291
 292     type = GLUT_DEPTH;
 293     type |= (rgb) ? GLUT_RGB : GLUT_INDEX;
 294     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
 295     glutInitDisplayMode(type);
 296
 297     if (glutCreateWindow("Fog Test") == GL_FALSE) {
 298         exit(1);
 299     }
 300
 301     InitMap();
 302
 303     Init();
 304
 305     glutReshapeFunc(Reshape);
 306     glutKeyboardFunc(Key);
 307     glutSpecialFunc(Key2);
 308     glutDisplayFunc(Draw);
 309     glutMainLoop();
 310         return 0;
 311 }