/* example1.c                                                      */
/*                                                                 */
/* This small program shows how to print a rotated string with the */
/* FreeType 2 library.                                             */

#include <stdio.h>
#include <string.h>
#include <math.h>

#include <ft2build.h>
#include FT_FREETYPE_H


#define WIDTH   400
#define HEIGHT  400
#include <gd.h>

/* origin is the upper left corner */
unsigned char image[HEIGHT][WIDTH];

/* Replace this function with something useful. */
void
draw_bitmap( FT_Bitmap*  bitmap,
             FT_Int      x,
             FT_Int      y)
{
  FT_Int  i, j, p, q;
  FT_Int  x_max = x + bitmap->width;
  FT_Int  y_max = y + bitmap->rows;

  for ( i = x, p = 0; i < x_max; i++, p++ )
  {
    for ( j = y, q = 0; j < y_max; j++, q++ )
    {
      if ( i < 0      || j < 0       ||
           i >= WIDTH || j >= HEIGHT )
        continue;

      image[j][i] |= bitmap->buffer[q * bitmap->width + p];
    }
  }
}


void show_image( void )
{
	int  i, j;
	gdImagePtr im;
	FILE *fp;

	im = gdImageCreateTrueColor(WIDTH, HEIGHT);

	for ( i = 0; i < HEIGHT; i++ ) {
		for ( j = 0; j < WIDTH; j++ ) {
			gdImageSetPixel(im, j, i, gdTrueColorAlpha(255, 255, 255, 127 - 127 * (image[i][j]) * 1/255));
		}
	}

	fp = fopen("test3.png", "wb");
 	gdImagePng(im,fp);
	fclose(fp);

	gdImageDestroy(im);
}


int
main( int     argc,
      char**  argv )
{
	FT_Library    library;
	FT_Face       face;

	FT_GlyphSlot  slot;
	FT_Matrix     matrix;                 /* transformation matrix */
	FT_Vector     pen;                    /* untransformed origin  */
	FT_Error      error;

	char*         filename;
	char*         text;

	double        angle;
	double        size;
	int           target_height;
	int           n, num_chars, i;


	if ( argc != 4 ) {
		fprintf ( stderr, "usage: %s font size sample-text\n", argv[0] );
		exit( 1 );
	}

	filename      = argv[1];                           /* first argument     */
	size          = atof(argv[2]);                     /* second argument    */
	text          = argv[3];                           /* second argument    */
	num_chars     = strlen( text );
	angle         = ( 25.0 / 360 ) * 3.14159 * 2;      /* use 25 degrees     */
	angle         = 0;
	target_height = HEIGHT;

	error = FT_Init_FreeType( &library );              /* initialize library */
	/* error handling omitted */

	error = FT_New_Face( library, argv[1], 0, &face ); /* create face object */
	/* error handling omitted */

	/* use 50pt at 100dpi */
	error = FT_Set_Char_Size( face, size * 64, 0,
									 100, 100 );                /* set character size */

	/* error handling omitted */
	slot = face->glyph;
	for(i = 0; i < 4; i++){
		/* set up matrix */
		matrix.xx = (FT_Fixed)( cos( angle ) * 0x10000L );
		matrix.xy = (FT_Fixed)(-sin( angle ) * 0x10000L );
		matrix.yx = (FT_Fixed)( sin( angle ) * 0x10000L );
		matrix.yy = (FT_Fixed)( cos( angle ) * 0x10000L );

		/* the pen position in 26.6 cartesian space coordinates; */
		/* start at (300,200) relative to the upper left corner  */
		pen.x = WIDTH/2 * 64;
		pen.y = ( target_height - 200 ) * 64;

		for ( n = 0; n < num_chars; n++ ) {
			/* set transformation */
			FT_Set_Transform( face, &matrix, &pen );

			/* load glyph image into the slot (erase previous one) */
			error = FT_Load_Char( face, text[n], FT_LOAD_RENDER );
			if ( error ) {
				continue;                 /* ignore errors */
			}

			/* now, draw to our target surface (convert position) */
			draw_bitmap(&slot->bitmap,
						  slot->bitmap_left,
						  target_height - slot->bitmap_top);

			/* increment pen position */
			pen.x += slot->advance.x;
			pen.y += slot->advance.y;
		}
		angle += M_PI_2;
	}

	show_image();

	FT_Done_Face    ( face );
	FT_Done_FreeType( library );

  return 0;
}
