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- /* pnmflip.c - perform one or more flip operations on a portable anymap
- **
- ** Copyright (C) 1989 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 "pnm.h"
-
- static void leftright ARGS(( int* aP, int* bP, int* cP, int* dP, int* eP, int* fP ));
- static void topbottom ARGS(( int* aP, int* bP, int* cP, int* dP, int* eP, int* fP ));
- static void transpose ARGS(( int* aP, int* bP, int* cP, int* dP, int* eP, int* fP ));
-
- int
- main( argc, argv )
- int argc;
- char* argv[];
- {
- FILE* ifp;
- int argn, cols, rows, format, newrows, newcols;
- int a, b, c, d, e, f;
- register int row, col, newrow, newcol;
- xelval maxval;
- char* usage = "[-leftright|-lr] [-topbottom|-tb] [-transpose|-xy]\n [-rotate90|-r90|-ccw] [-rotate270|r270|-cw]\n [-rotate180|-r180] [pnmfile]";
-
- pnm_init( &argc, argv );
-
- argn = 1;
-
- /* Just check the validity of arguments here. */
- while ( argn < argc && argv[argn][0] == '-' && argv[argn][1] != '\0' )
- {
- if ( pm_keymatch( argv[argn], "-lr", 2 ) ||
- pm_keymatch( argv[argn], "-leftright", 2 ) )
- { }
- else if ( pm_keymatch( argv[argn], "-tb", 3 ) ||
- pm_keymatch( argv[argn], "-topbottom", 3 ) )
- { }
- else if ( pm_keymatch( argv[argn], "-xy", 2 ) ||
- pm_keymatch( argv[argn], "-transpose", 3 ) )
- { }
- else if ( pm_keymatch( argv[argn], "-r90", 3 ) ||
- pm_keymatch( argv[argn], "-rotate90", 8 ) ||
- pm_keymatch( argv[argn], "-ccw", 3 ) )
- { }
- else if ( pm_keymatch( argv[argn], "-r270", 3 ) ||
- pm_keymatch( argv[argn], "-rotate270", 8 ) ||
- pm_keymatch( argv[argn], "-cw", 3 ) )
- { }
- else if ( pm_keymatch( argv[argn], "-r180", 3 ) ||
- pm_keymatch( argv[argn], "-rotate180", 8 ) )
- { }
- else
- pm_usage( usage );
- ++argn;
- }
-
- if ( argn != argc )
- {
- ifp = pm_openr( argv[argn] );
- ++argn;
- }
- else
- ifp = stdin;
-
- if ( argn != argc )
- pm_usage( usage );
-
- pnm_readpnminit( ifp, &cols, &rows, &maxval, &format );
-
- /* Now go through the flags again, this time accumulating transforms. */
- a = 1; b = 0;
- c = 0; d = 1;
- e = 0; f = 0;
- argn = 1;
- while ( argn < argc && argv[argn][0] == '-' )
- {
- if ( pm_keymatch( argv[argn], "-lr", 2 ) ||
- pm_keymatch( argv[argn], "-leftright", 2 ) )
- leftright( &a, &b, &c, &d, &e, &f );
- else if ( pm_keymatch( argv[argn], "-tb", 3 ) ||
- pm_keymatch( argv[argn], "-topbottom", 3 ) )
- topbottom( &a, &b, &c, &d, &e, &f );
- else if ( pm_keymatch( argv[argn], "-xy", 2 ) ||
- pm_keymatch( argv[argn], "-transpose", 3 ) )
- transpose( &a, &b, &c, &d, &e, &f );
- else if ( pm_keymatch( argv[argn], "-r90", 3 ) ||
- pm_keymatch( argv[argn], "-rotate90", 8 ) ||
- pm_keymatch( argv[argn], "-ccw", 3 ) )
- {
- transpose( &a, &b, &c, &d, &e, &f );
- topbottom( &a, &b, &c, &d, &e, &f );
- }
- else if ( pm_keymatch( argv[argn], "-r270", 3 ) ||
- pm_keymatch( argv[argn], "-rotate270", 8 ) ||
- pm_keymatch( argv[argn], "-cw", 3 ) )
- {
- transpose( &a, &b, &c, &d, &e, &f );
- leftright( &a, &b, &c, &d, &e, &f );
- }
- else if ( pm_keymatch( argv[argn], "-r180", 3 ) ||
- pm_keymatch( argv[argn], "-rotate180", 8 ) )
- {
- leftright( &a, &b, &c, &d, &e, &f );
- topbottom( &a, &b, &c, &d, &e, &f );
- }
- else
- pm_error( "shouldn't happen!" );
- ++argn;
- }
-
- /* Okay, we've got a matrix. */
- newcols = abs( a ) * cols + abs( c ) * rows;
- newrows = abs( b ) * cols + abs( d ) * rows;
-
- if ( b == 0 && d == 1 && f == 0 )
- {
- /* In this case newrow is always equal to row, so we can do the
- ** transform line by line and avoid in-memory buffering altogether.
- */
- register xel* xelrow;
- register xel* newxelrow;
- register xel* xP;
-
- xelrow = pnm_allocrow( cols );
- newxelrow = pnm_allocrow( newcols );
- pnm_writepnminit( stdout, newcols, newrows, maxval, format, 0 );
-
- for ( row = 0; row < rows; ++row )
- {
- pnm_readpnmrow( ifp, xelrow, cols, maxval, format );
- for ( col = 0, xP = xelrow; col < cols; ++col, ++xP )
- {
- /* Transform a point:
- **
- ** [ a b 0 ]
- ** [ x y 1 ] [ c d 0 ] = [ x2 y2 1 ]
- ** [ e f 1 ]
- */
- newcol = a * col + c * row + e * ( newcols - 1 );
- newxelrow[newcol] = *xP;
- }
- pnm_writepnmrow( stdout, newxelrow, newcols, maxval, format, 0 );
- }
- }
- #ifdef notdef
- else if ( a == 0 && b != 0 && c != 0 && d == 0 )
- {
- /* This case is likely to thrash. Can't think of any fix at the
- ** moment, though.
- */
- }
- #endif /* notdef */
- else
- {
- /* Generic case. Read in the anymap a line at a time and transform
- ** it into an in-memory array.
- */
- register xel* xelrow;
- register xel** newxels;
- register xel* xP;
-
- xelrow = pnm_allocrow( cols );
- newxels = pnm_allocarray( newcols, newrows );
-
- for ( row = 0; row < rows; ++row )
- {
- pnm_readpnmrow( ifp, xelrow, cols, maxval, format );
- for ( col = 0, xP = xelrow; col < cols; ++col, ++xP )
- {
- /* Transform a point:
- **
- ** [ a b 0 ]
- ** [ x y 1 ] [ c d 0 ] = [ x2 y2 1 ]
- ** [ e f 1 ]
- */
- newcol = a * col + c * row + e * ( newcols - 1 );
- newrow = b * col + d * row + f * ( newrows - 1 );
- newxels[newrow][newcol] = *xP;
- }
- }
-
- pnm_writepnm( stdout, newxels, newcols, newrows, maxval, format, 0 );
- }
-
- pm_close( ifp );
- pm_close( stdout );
-
- exit( 0 );
- }
-
- static void
- leftright( aP, bP, cP, dP, eP, fP )
- int* aP;
- int* bP;
- int* cP;
- int* dP;
- int* eP;
- int* fP;
- {
- *aP = - *aP;
- *cP = - *cP;
- *eP = - *eP + 1;
- }
-
- static void
- topbottom( aP, bP, cP, dP, eP, fP )
- int* aP;
- int* bP;
- int* cP;
- int* dP;
- int* eP;
- int* fP;
- {
- *bP = - *bP;
- *dP = - *dP;
- *fP = - *fP + 1;
- }
-
- static void
- transpose( aP, bP, cP, dP, eP, fP )
- int* aP;
- int* bP;
- int* cP;
- int* dP;
- int* eP;
- int* fP;
- {
- register int t;
-
- t = *aP;
- *aP = *bP;
- *bP = t;
- t = *cP;
- *cP = *dP;
- *dP = t;
- t = *eP;
- *eP = *fP;
- *fP = t;
- }
-