/*  gif_to_gl.c  uses gifread to input a .gif file, needs gif.h */

#include <GL/glut.h>

static char filename[] = "smlogo.gif";
static GLubyte rgbpix[3*39*44]; /* size bigger than smlogo.gif */
static width = 39;              /* also read in */
static height = 44; 
static alpha = -1;

static char filename2[] = "line.gif";
static GLubyte rgbpix2[4*100*50]; /* size for line.gif */
static width2 = 100;              /* also read in */
static height2 = 50; 
static alpha2 = 255;

void display(void)
{
  char *p;
  GLubyte pixels[3];
  int x=100, y=100;
  
  /* clear window */
  glClear(GL_COLOR_BUFFER_BIT); 
  glLoadIdentity ();
  glColor3f(0.0, 0.0, 0.0);


  /* draw .gif files */  
  glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
  glRasterPos2f(-.75, -.75);
  glDrawPixels(width, height, GL_RGB, GL_UNSIGNED_BYTE, rgbpix);
  glRasterPos2f(0.0, 0.0);
  glDrawPixels(width2, height2, GL_RGBA, GL_UNSIGNED_BYTE, rgbpix2);
  
  
  /* draw text */
  glEnable(GL_LINE_SMOOTH);
  glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
  glEnable(GL_BLEND);
  glLoadIdentity ();
  glTranslatef(-0.2, -0.6, 0.0);
  glScalef(0.0015, 0.0015, 0.0);
  for(p=filename; *p; p++)
    glutStrokeCharacter(GLUT_STROKE_ROMAN, *p);
  glLoadIdentity ();
  glTranslatef(0.1, 0.6, 0.0);
  glScalef(0.0015, 0.0015, 0.0);
  for(p=filename2; *p; p++)
    glutStrokeCharacter(GLUT_STROKE_ROMAN, *p);
  glFlush(); 
}

void myreshape(int h, int w)
{
  glMatrixMode(GL_PROJECTION);
  glLoadIdentity();
  gluOrtho2D(-1.0, 1.0, -1.0, 1.0);
  glMatrixMode(GL_MODELVIEW);
  glLoadIdentity();
  glViewport(0,0,h,w);
}

void init()
{
  int status, i, j, k;
  
  printf("test_gifread calling gifread on file %s\n", filename);
  status = gifread("smlogo.gif", alpha, &width, &height, rgbpix);
  printf("gifread returned status=%d, width=%d, height=%d, alpha=%d \n",
         status, width, height, alpha);
  status = gifread("line.gif", alpha2, &width2, &height2, rgbpix2);
  printf("gifread returned status=%d, width2=%d, height2=%d, alpha2=%d \n",
         status, width2, height2, alpha2);

  /* set clear color to green */
  glClearColor (0.0, 1.0, 0.0, 0.0);
  /* set fill  color to black */

  glMatrixMode(GL_PROJECTION);
  glLoadIdentity();
  gluOrtho2D(-1.0, 1.0, -1.0, 1.0);
  glMatrixMode(GL_MODELVIEW);
  glLoadIdentity();
  glViewport(0,0,200,200);
}

int main(int argc, char* argv[])
{
  glutInit(&argc,argv);
  glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);  
  glutInitWindowSize(200,200);
  glutInitWindowPosition(100,100); 
  
  glutCreateWindow(argv[0]);
  glutReshapeFunc(myreshape);
  glutDisplayFunc(display);
  init();
  glutMainLoop();
  return 0;
}