1 files changed, 108 insertions, 0 deletions
diff --git a/converter/ppm/sputoppm.c b/converter/ppm/sputoppm.c
new file mode 100644
index 00000000..2671bffa
--- /dev/null
+++ b/converter/ppm/sputoppm.c
@@ -0,0 +1,108 @@
+/* sputoppm.c - read an uncompressed Spectrum file and produce a portable pixmap
+**
+** Copyright (C) 1991 by Steve Belczyk and 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 "ppm.h"
+
+#define ROWS 200
+#define COLS 320
+#define MAXVAL 7
+
+static pixel pal[ROWS][48];                /* Spectrum palettes, three per row */
+static short screen[ROWS*COLS/4];          /* simulates the Atari's video RAM */
+
+int
+main( argc, argv )
+    int argc;
+    char* argv[];
+    {
+    FILE* ifp;
+    int i, j;
+    pixel* pixelrow;
+    register pixel* pP;
+    int row, col;
+
+
+    ppm_init( &argc, argv );
+
+    /* Check args. */
+    if ( argc > 2 )
+        pm_usage( "[spufile]" );
+
+    if ( argc == 2 )
+        ifp = pm_openr( argv[1] );
+    else
+        ifp = stdin;
+
+    /* Read the SPU file */
+
+    /* Read the screen data. */
+    for ( i = 0; i < ROWS*COLS/4; ++i )
+        (void) pm_readbigshort( ifp, &screen[i] );
+
+    /* Clear the first palette line. */
+    for ( j = 0; j < 48; ++j )
+        PPM_ASSIGN( pal[0][j], 0, 0, 0 );
+
+    /* Read the palettes. */
+    for ( i = 1; i < ROWS; ++i )
+        for ( j = 0; j < 48; ++j )
+            {
+            short k;
+            (void) pm_readbigshort( ifp, &k );
+            PPM_ASSIGN( pal[i][j],
+                ( k & 0x700 ) >> 8,
+                ( k & 0x070 ) >> 4,
+                ( k & 0x007 ) );
+            }
+
+    pm_close( ifp );
+
+    /* Ok, get set for writing PPM. */
+    ppm_writeppminit( stdout, COLS, ROWS, (pixval) MAXVAL, 0 );
+    pixelrow = ppm_allocrow( COLS );
+
+    /* Now do the conversion. */
+    for ( row = 0; row < ROWS; ++row )
+        {
+        for ( col = 0, pP = pixelrow; col < COLS; ++col, ++pP )
+            {
+            int c, ind, b, plane, x1;
+
+            /* Compute pixel value. */
+            ind = 80 * row + ( ( col >> 4 ) << 2 );
+            b = 0x8000 >> (col & 0xf);
+            c = 0;
+            for ( plane = 0; plane < 4; ++plane )
+                if ( b & screen[ind+plane] )
+                    c |= (1 << plane);
+
+            /* Compute palette index. */
+            x1 = 10 * c;
+            if ( c & 1 )
+                x1 -= 5;
+            else
+                ++x1;
+            if ( ( col >= x1 ) && ( col < ( x1 + 160 ) ) )
+                c += 16;
+            if ( col >= ( x1 + 160 ) )
+                c += 32;
+
+            /* Store the proper color. */
+            *pP = pal[row][c];
+            }
+        ppm_writeppmrow( stdout, pixelrow, COLS, (pixval) MAXVAL, 0 );
+        }
+
+    pm_close( stdout );
+
+    exit( 0 );
+    }