1
2/* Copyright (c) Mark J. Kilgard, 1994. */
3
4/*
5 * (c) Copyright 1993, Silicon Graphics, Inc.
6 * ALL RIGHTS RESERVED
7 * Permission to use, copy, modify, and distribute this software for
8 * any purpose and without fee is hereby granted, provided that the above
9 * copyright notice appear in all copies and that both the copyright notice
10 * and this permission notice appear in supporting documentation, and that
11 * the name of Silicon Graphics, Inc. not be used in advertising
12 * or publicity pertaining to distribution of the software without specific,
13 * written prior permission.
14 *
15 * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU "AS-IS"
16 * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,
17 * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR
18 * FITNESS FOR A PARTICULAR PURPOSE.  IN NO EVENT SHALL SILICON
19 * GRAPHICS, INC.  BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,
20 * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY
21 * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,
22 * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF
23 * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC.  HAS BEEN
24 * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON
25 * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE
26 * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.
27 *
28 * US Government Users Restricted Rights
29 * Use, duplication, or disclosure by the Government is subject to
30 * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph
31 * (c)(1)(ii) of the Rights in Technical Data and Computer Software
32 * clause at DFARS 252.227-7013 and/or in similar or successor
33 * clauses in the FAR or the DOD or NASA FAR Supplement.
34 * Unpublished-- rights reserved under the copyright laws of the
35 * United States.  Contractor/manufacturer is Silicon Graphics,
36 * Inc., 2011 N.  Shoreline Blvd., Mountain View, CA 94039-7311.
37 *
38 * OpenGL(TM) is a trademark of Silicon Graphics, Inc.
39 */
40/*
41 *  stroke.c
42 *  This program demonstrates some characters of a
43 *  stroke (vector) font.  The characters are represented
44 *  by display lists, which are given numbers which
45 *  correspond to the ASCII values of the characters.
46 *  Use of glCallLists() is demonstrated.
47 */
48#include <stdlib.h>
49#include <string.h>
50#include "glut_wrap.h"
51
52#define PT 1
53#define STROKE 2
54#define END 3
55
56typedef struct charpoint {
57    GLfloat   x, y;
58    int    type;
59} CP;
60
61CP Adata[] = {
62    { 0, 0, PT}, {0, 9, PT}, {1, 10, PT}, {4, 10, PT},
63    {5, 9, PT}, {5, 0, STROKE}, {0, 5, PT}, {5, 5, END}
64};
65
66CP Edata[] = {
67    {5, 0, PT}, {0, 0, PT}, {0, 10, PT}, {5, 10, STROKE},
68    {0, 5, PT}, {4, 5, END}
69};
70
71CP Pdata[] = {
72    {0, 0, PT}, {0, 10, PT},  {4, 10, PT}, {5, 9, PT}, {5, 6, PT},
73    {4, 5, PT}, {0, 5, END}
74};
75
76CP Rdata[] = {
77    {0, 0, PT}, {0, 10, PT},  {4, 10, PT}, {5, 9, PT}, {5, 6, PT},
78    {4, 5, PT}, {0, 5, STROKE}, {3, 5, PT}, {5, 0, END}
79};
80
81CP Sdata[] = {
82    {0, 1, PT}, {1, 0, PT}, {4, 0, PT}, {5, 1, PT}, {5, 4, PT},
83    {4, 5, PT}, {1, 5, PT}, {0, 6, PT}, {0, 9, PT}, {1, 10, PT},
84    {4, 10, PT}, {5, 9, END}
85};
86
87/*  drawLetter() interprets the instructions from the array
88 *  for that letter and renders the letter with line segments.
89 */
90static void drawLetter(CP *l)
91{
92    glBegin(GL_LINE_STRIP);
93    for (;;) {
94	switch (l->type) {
95	    case PT:
96		glVertex2fv(&l->x);
97		break;
98	    case STROKE:
99		glVertex2fv(&l->x);
100		glEnd();
101		glBegin(GL_LINE_STRIP);
102		break;
103	    case END:
104		glVertex2fv(&l->x);
105		glEnd();
106		glTranslatef(8.0, 0.0, 0.0);
107		return;
108	}
109	l++;
110    }
111}
112
113/*  Create a display list for each of 6 characters	*/
114static void myinit (void)
115{
116    GLuint base;
117
118    glShadeModel (GL_FLAT);
119
120    base = glGenLists (128);
121    glListBase(base);
122    glNewList(base+'A', GL_COMPILE); drawLetter(Adata); glEndList();
123    glNewList(base+'E', GL_COMPILE); drawLetter(Edata); glEndList();
124    glNewList(base+'P', GL_COMPILE); drawLetter(Pdata); glEndList();
125    glNewList(base+'R', GL_COMPILE); drawLetter(Rdata); glEndList();
126    glNewList(base+'S', GL_COMPILE); drawLetter(Sdata); glEndList();
127    glNewList(base+' ', GL_COMPILE); glTranslatef(8.0, 0.0, 0.0); glEndList();
128}
129
130char *test1 = "A SPARE SERAPE APPEARS AS";
131char *test2 = "APES PREPARE RARE PEPPERS";
132
133static void printStrokedString(char *s)
134{
135    GLsizei len = (GLsizei) strlen(s);
136    glCallLists(len, GL_BYTE, (GLbyte *)s);
137}
138
139static void display(void)
140{
141    glClear(GL_COLOR_BUFFER_BIT);
142    glColor3f(1.0, 1.0, 1.0);
143    glPushMatrix();
144    glScalef(2.0, 2.0, 2.0);
145    glTranslatef(10.0, 30.0, 0.0);
146    printStrokedString(test1);
147    glPopMatrix();
148    glPushMatrix();
149    glScalef(2.0, 2.0, 2.0);
150    glTranslatef(10.0, 13.0, 0.0);
151    printStrokedString(test2);
152    glPopMatrix();
153    glFlush();
154}
155
156static void reshape(GLsizei w, GLsizei h)
157{
158    glViewport(0, 0, w, h);
159    glMatrixMode(GL_PROJECTION);
160    glLoadIdentity();
161    glOrtho(0.0, (GLdouble)w, 0.0, (GLdouble)h, -1.0, 1.0);
162    glMatrixMode(GL_MODELVIEW);
163    glLoadIdentity();
164}
165
166static void
167key(unsigned char k, int x, int y)
168{
169  switch (k) {
170  case 27:  /* Escape */
171    exit(0);
172    break;
173  default:
174    return;
175  }
176  glutPostRedisplay();
177}
178
179/*  Main Loop
180 *  Open window with initial window size, title bar,
181 *  RGBA display mode, and handle input events.
182 */
183int main(int argc, char** argv)
184{
185    glutInit(&argc, argv);
186    glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);
187    glutInitWindowSize (440, 120);
188    glutCreateWindow (argv[0]);
189    myinit ();
190    glutDisplayFunc(display);
191    glutReshapeFunc(reshape);
192    glutKeyboardFunc(key);
193    glutMainLoop();
194    return 0;             /* ANSI C requires main to return int. */
195}
196