STROKE.C

/* 
 * (c) Copyright 1993, Silicon Graphics, Inc. 
 *               1993-1995 Microsoft Corporation 
 * 
 * ALL RIGHTS RESERVED 
 * 
 * Please refer to OpenGL/readme.txt for additional information 
 * 
 */ 
 
/* 
 *  stroke.c  
 *  This program demonstrates some characters of a  
 *  stroke (vector) font.  The characters are represented 
 *  by display lists, which are given numbers which  
 *  correspond to the ASCII values of the characters. 
 *  Use of glCallLists() is demonstrated. 
 */ 
#include "glos.h" 
 
#include <GL/gl.h> 
#include <GL/glu.h> 
#include <GL/glaux.h> 
 
typedef struct charpoint { 
    GLfloat   x, y; 
    int    type; 
} CP; 
 
void myinit(void); 
void drawLetter(CP *l); 
void printStrokedString(char *s); 
void CALLBACK display(void); 
void CALLBACK myReshape(GLsizei w, GLsizei h); 
 
#define PT 1 
#define STROKE 2 
#define END 3 
 
 
CP Adata[] = { 
    { 0, 0, PT}, {0, 9, PT}, {1, 10, PT}, {4, 10, PT},  
    {5, 9, PT}, {5, 0, STROKE}, {0, 5, PT}, {5, 5, END} 
}; 
 
CP Edata[] = { 
    {5, 0, PT}, {0, 0, PT}, {0, 10, PT}, {5, 10, STROKE}, 
    {0, 5, PT}, {4, 5, END} 
}; 
 
CP Pdata[] = { 
    {0, 0, PT}, {0, 10, PT},  {4, 10, PT}, {5, 9, PT}, {5, 6, PT},  
    {4, 5, PT}, {0, 5, END} 
}; 
 
CP Rdata[] = { 
    {0, 0, PT}, {0, 10, PT},  {4, 10, PT}, {5, 9, PT}, {5, 6, PT},  
    {4, 5, PT}, {0, 5, STROKE}, {3, 5, PT}, {5, 0, END} 
}; 
 
CP Sdata[] = { 
    {0, 1, PT}, {1, 0, PT}, {4, 0, PT}, {5, 1, PT}, {5, 4, PT},  
    {4, 5, PT}, {1, 5, PT}, {0, 6, PT}, {0, 9, PT}, {1, 10, PT},  
    {4, 10, PT}, {5, 9, END} 
}; 
 
/*  drawLetter() interprets the instructions from the array 
 *  for that letter and renders the letter with line segments. 
 */ 
void drawLetter(CP *l) 
{ 
    glBegin(GL_LINE_STRIP); 
    while (1) { 
    switch (l->type) { 
        case PT: 
        glVertex2fv(&l->x); 
        break; 
        case STROKE: 
        glVertex2fv(&l->x); 
        glEnd(); 
        glBegin(GL_LINE_STRIP); 
        break; 
        case END: 
        glVertex2fv(&l->x); 
        glEnd(); 
        glTranslatef(8.0, 0.0, 0.0); 
        return; 
    } 
    l++; 
    } 
} 
 
/*  Create a display list for each of 6 characters  */ 
void myinit (void) 
{ 
    GLuint base; 
 
    glShadeModel (GL_FLAT); 
 
    base = glGenLists (128); 
    glListBase(base); 
    glNewList(base+'A', GL_COMPILE); drawLetter(Adata); glEndList(); 
    glNewList(base+'E', GL_COMPILE); drawLetter(Edata); glEndList(); 
    glNewList(base+'P', GL_COMPILE); drawLetter(Pdata); glEndList(); 
    glNewList(base+'R', GL_COMPILE); drawLetter(Rdata); glEndList(); 
    glNewList(base+'S', GL_COMPILE); drawLetter(Sdata); glEndList(); 
    glNewList(base+' ', GL_COMPILE); glTranslatef(8.0, 0.0, 0.0); glEndList(); 
} 
 
char *test1 = "A SPARE SERAPE APPEARS AS"; 
char *test2 = "APES PREPARE RARE PEPPERS"; 
 
void printStrokedString(char *s) 
{ 
    GLsizei len = strlen(s); 
    glCallLists(len, GL_BYTE, (GLbyte *)s); 
} 
 
void CALLBACK display(void) 
{ 
    glClear(GL_COLOR_BUFFER_BIT); 
    glColor3f(1.0, 1.0, 1.0); 
    glPushMatrix(); 
    glScalef(2.0, 2.0, 2.0); 
    glTranslatef(10.0, 30.0, 0.0); 
    printStrokedString(test1); 
    glPopMatrix(); 
    glPushMatrix(); 
    glScalef(2.0, 2.0, 2.0); 
    glTranslatef(10.0, 13.0, 0.0); 
    printStrokedString(test2); 
    glPopMatrix(); 
    glFlush(); 
} 
 
/*  Main Loop 
 *  Open window with initial window size, title bar,  
 *  RGBA display mode, and handle input events. 
 */ 
int main(int argc, char** argv) 
{ 
    auxInitDisplayMode (AUX_SINGLE | AUX_RGB); 
    auxInitPosition (0, 0, 440, 120); 
    auxInitWindow ("Stroke Font"); 
    myinit (); 
    auxMainLoop(display); 
    return(0); 
}