$NetBSD: patch-am,v 1.1 1999/01/10 23:52:16 tron Exp $

--- pnm/pnmarith.c.orig	Wed Jan  5 11:04:53 1994
+++ pnm/pnmarith.c	Sun Jan 10 23:48:40 1999
@@ -29,7 +29,8 @@
     xelval maxval1, maxval2, maxval3;
     int argn, rows1, cols1, format1, rows2, cols2, format2, format3, row, col;
     char function;
-    char* usage = "-add|-subtract|-multiply|-difference pnmfile1 pnmfile2";
+    char* usage =
+"-add|-subtract|-multiply|-difference|-minimum|-maximum pnmfile1 pnmfile2";
 
 
     pnm_init( &argc, argv );
@@ -48,6 +49,10 @@
 	    function = '*';
 	else if ( pm_keymatch( argv[argn], "-difference", 2 ) )
 	    function = 'D';
+	else if ( pm_keymatch( argv[argn], "-minimum", 2 ) )
+	    function = 'N';
+	else if ( pm_keymatch( argv[argn], "-maximum", 2 ) )
+	    function = 'X';
 	else
 	    pm_usage( usage );
 	++argn;
@@ -112,7 +117,7 @@
 	    pnm_promoteformatrow(
 		xelrow2, cols1, maxval2, format2, maxval3, format3 );
 
-        for ( col = 0, x1P = xelrow1, x2P = xelrow2;
+	for ( col = 0, x1P = xelrow1, x2P = xelrow2;
 	      col < cols1; ++col, ++x1P, ++x2P )
 	    {
 	    switch ( PNM_FORMAT_TYPE(format3) )
@@ -153,6 +158,18 @@
 		    b1 = (b1>b2)?(b1-b2):(b2-b1);
 		    break;
 
+		    case 'N':
+		    r1 = (r1>r2)?(r2):(r1);
+		    g1 = (g1>g2)?(g2):(g1);
+		    b1 = (b1>b2)?(b2):(b1);
+		    break;
+  
+		    case 'X':
+		    r1 = (r1>r2)?(r1):(r2);
+		    g1 = (g1>g2)?(g1):(g2);
+		    b1 = (b1>b2)?(b1):(b2);
+		    break;
+
 		    default:
 		    pm_error( "can't happen" );
 		    }
@@ -188,6 +205,14 @@
 
 		    case 'D':
 		    g1 = (g1>g2)?(g1-g2):(g2-g1);
+		    break;
+
+		    case 'N':
+		    g1 = (g1>g2)?(g2):(g1);
+		    break;
+  
+		    case 'X':
+		    g1 = (g1>g2)?(g1):(g2);
 		    break;
 
 		    default: