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- /* brushtopbm.c - read a doodle brush file and write a portable bitmap
- **
- ** Copyright (C) 1988 by Jef Poskanzer.
- **
- ** Permission to use, copy, modify, and distribute this software and its
- ** documentation for any purpose and without fee is hereby granted, provided
- ** that the above copyright notice appear in all copies and that both that
- ** copyright notice and this permission notice appear in supporting
- ** documentation. This software is provided "as is" without express or
- ** implied warranty.
- */
-
- #include "pbm.h"
-
- static void getinit ARGS(( FILE* file, int* colsP, int* rowsP ));
- static bit getbit ARGS(( FILE* file ));
-
- int
- main( argc, argv )
- int argc;
- char* argv[];
- {
- FILE* ifp;
- bit* bitrow;
- register bit* bP;
- int rows, cols, padright, row, col;
-
-
- pbm_init( &argc, argv );
-
- if ( argc > 2 )
- pm_usage( "[brushfile]" );
-
- if ( argc == 2 )
- ifp = pm_openr( argv[1] );
- else
- ifp = stdin;
-
- getinit( ifp, &cols, &rows );
-
- pbm_writepbminit( stdout, cols, rows, 0 );
- bitrow = pbm_allocrow( cols );
-
- /* Compute padding to round cols up to the next multiple of 16. */
- padright = ( ( cols + 15 ) / 16 ) * 16 - cols;
-
- for ( row = 0; row < rows; ++row )
- {
- /* Get data. */
- for ( col = 0, bP = bitrow; col < cols; ++col, ++bP )
- *bP = getbit( ifp );
- /* Discard line padding. */
- for ( col = 0; col < padright; ++col )
- (void) getbit( ifp );
- /* Write row. */
- pbm_writepbmrow( stdout, bitrow, cols, 0 );
- }
-
- pm_close( ifp );
- pm_close( stdout );
-
- exit( 0 );
- }
-
-
- static int item, bitsperitem, bitshift;
-
- static void
- getinit( file, colsP, rowsP )
- FILE* file;
- int* colsP;
- int* rowsP;
- {
- int i;
-
- if ( getc( file ) != 1 )
- pm_error( "bad magic number 1" );
- if ( getc( file ) != 0 )
- pm_error( "bad magic number 2" );
- *colsP = getc( file ) << 8;
- *colsP += getc( file );
- *rowsP = getc( file ) << 8;
- *rowsP += getc( file );
- bitsperitem = 8;
-
- /* Junk rest of header. */
- for ( i = 0; i < 10; ++i ) /* 10 is just a guess at the header size */
- (void) getc( file );
- }
-
- static bit
- getbit( file )
- FILE* file;
- {
- bit b;
-
- if ( bitsperitem == 8 )
- {
- item = getc( file );
- bitsperitem = 0;
- bitshift = 7;
- }
- ++bitsperitem;
- b = ( ( item >> bitshift) & 1 ) ? PBM_WHITE : PBM_BLACK;
- --bitshift;
- return b;
- }
-