Create Subversion repository

git-svn-id: http://svn.code.sf.net/p/netpbm/code/trunk@1 9d0c8265-081b-0410-96cb-a4ca84ce46f8

1 files changed, 170 insertions, 0 deletions

diff --git a/generator/pgmramp.c b/generator/pgmramp.c
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--- /dev/null
+++ b/generator/pgmramp.c
@@ -0,0 +1,170 @@
+/* pgmramp.c - generate a grayscale ramp
+**
+** 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 <math.h>
+#include "pgm.h"
+#include "shhopt.h"
+
+enum ramptype {RT_LR, RT_TB, RT_RECT, RT_ELLIP};
+
+
+struct cmdlineInfo {
+    /* All the information the user supplied in the command line,
+       in a form easy for the program to use.
+    */
+    enum ramptype ramptype;
+    unsigned int cols;
+    unsigned int rows;
+    gray maxval;
+};
+
+
+
+static void
+parseCommandLine(int argc, char ** argv,
+                 struct cmdlineInfo * const cmdlineP) {
+/*----------------------------------------------------------------------------
+  Convert program invocation arguments (argc,argv) into a format the 
+  program can use easily, struct cmdlineInfo.  Validate arguments along
+  the way and exit program with message if invalid.
+
+  Note that some string information we return as *cmdlineP is in the storage 
+  argv[] points to.
+-----------------------------------------------------------------------------*/
+    optEntry *option_def = malloc(100*sizeof(optEntry));
+        /* Instructions to OptParseOptions2 on how to parse our options.
+         */
+    optStruct3 opt;
+
+    unsigned int lrSpec, tbSpec, rectangleSpec, ellipseSpec;
+    unsigned int maxvalSpec;
+    unsigned int option_def_index;
+
+    option_def_index = 0;   /* incremented by OPTENTRY */
+    OPTENT3(0,   "lr",        OPT_FLAG, NULL,              &lrSpec,        0);
+    OPTENT3(0,   "tb",        OPT_FLAG, NULL,              &tbSpec,        0);
+    OPTENT3(0,   "rectangle", OPT_FLAG, NULL,              &rectangleSpec, 0);
+    OPTENT3(0,   "ellipse",   OPT_FLAG, NULL,              &ellipseSpec,   0);
+    OPTENT3(0,   "maxval",    OPT_UINT, &cmdlineP->maxval, &maxvalSpec,    0);
+
+    opt.opt_table = option_def;
+    opt.short_allowed = FALSE;  /* We have no short (old-fashioned) options */
+    opt.allowNegNum = FALSE;  /* We have no parms that are negative numbers */
+
+    optParseOptions3(&argc, argv, opt, sizeof(opt), 0);
+        /* Uses and sets argc, argv, and some of *cmdlineP and others. */
+
+    if (lrSpec + tbSpec + rectangleSpec + ellipseSpec == 0)
+        pm_error("You must specify one of -lr, -tb, -rectangle, or -ellipse");
+    if (lrSpec + tbSpec + rectangleSpec + ellipseSpec > 1)
+        pm_error("You may specify at most one of "
+                 "-lr, -tb, -rectangle, or -ellipse");
+    if (lrSpec)
+        cmdlineP->ramptype = RT_LR;
+    else if (tbSpec)
+        cmdlineP->ramptype = RT_TB;
+    else if (rectangleSpec)
+        cmdlineP->ramptype = RT_RECT;
+    else if (ellipseSpec)
+        cmdlineP->ramptype = RT_ELLIP;
+    else
+        pm_error("INTERNAL ERROR - no ramp type option found");
+
+    if (!maxvalSpec)
+        cmdlineP->maxval = PGM_MAXMAXVAL;
+    else {
+        if (cmdlineP->maxval > PGM_OVERALLMAXVAL)
+            pm_error("The value you specified for -maxval (%u) is too big.  "
+                     "Max allowed is %u", cmdlineP->maxval, PGM_OVERALLMAXVAL);
+        
+        if (cmdlineP->maxval < 1)
+            pm_error("You cannot specify 0 for -maxval");
+    }    
+
+    if (argc-1 < 2)
+        pm_error("Need two arguments: width and height.");
+    else if (argc-1 > 2)
+        pm_error("Only two arguments allowed: width and height.  "
+                 "You specified %d", argc-1);
+    else {
+        cmdlineP->cols = atoi(argv[1]);
+        cmdlineP->rows = atoi(argv[2]);
+        if (cmdlineP->cols <= 0)
+            pm_error("width argument must be a positive number.  You "
+                     "specified '%s'", argv[1]);
+        if (cmdlineP->rows <= 0)
+            pm_error("height argument must be a positive number.  You "
+                     "specified '%s'", argv[2]);
+    }
+}
+
+
+
+int 
+main(int argc, char *argv[]) {
+
+    struct cmdlineInfo cmdline;
+    gray *grayrow;
+    int rowso2, colso2;
+    unsigned int row;
+
+    pgm_init( &argc, argv );
+
+    parseCommandLine(argc, argv, &cmdline);
+
+    colso2 = MAX(1, cmdline.cols / 2);
+    rowso2 = MAX(1, cmdline.rows / 2);
+    
+    pgm_writepgminit(stdout, cmdline.cols, cmdline.rows, cmdline.maxval, 0);
+    grayrow = pgm_allocrow(cmdline.cols);
+    
+    for (row = 0; row < cmdline.rows; ++row) {
+        unsigned int col;
+        for (col = 0; col < cmdline.cols; ++col) {
+            switch (cmdline.ramptype) {
+            case RT_LR:
+                grayrow[col] = 
+                    col * cmdline.maxval / MAX(cmdline.cols-1, 1);
+                break;
+            case RT_TB:
+                grayrow[col] = 
+                    row * cmdline.maxval / MAX(cmdline.rows-1, 1);
+                break;
+
+            case RT_RECT: {
+                float const r = fabs((int)(rowso2 - row)) / rowso2;
+                float const c = fabs((int)(colso2 - col)) / colso2;
+                grayrow[col] = 
+                    cmdline.maxval - (r + c) / 2.0 * cmdline.maxval;
+            }
+            break;
+            
+            case RT_ELLIP: {
+                float const r = fabs((int)(rowso2 - row)) / rowso2;
+                float const c = fabs((int)(colso2 - col)) / colso2;
+                float v;
+
+                v = r * r + c * c;
+                if ( v < 0.0 ) v = 0.0;
+                else if ( v > 1.0 ) v = 1.0;
+                grayrow[col] = cmdline.maxval - v * cmdline.maxval;
+            }
+            break;
+            }
+	    }
+        pgm_writepgmrow(stdout, grayrow, cmdline.cols, cmdline.maxval, 0);
+	}
+
+    pgm_freerow(grayrow);
+    pm_close(stdout);
+    return 0;
+}