moving trunk for module inkscape

(bzr r1)

1 files changed, 485 insertions, 0 deletions

diff --git a/src/svg/ftos.cpp b/src/svg/ftos.cpp
new file mode 100644
index 000000000..c468b4c63
--- /dev/null
+++ b/src/svg/ftos.cpp
@@ -0,0 +1,485 @@
+/* //////////////////////////////////////////////////////////////////////
+//                               ftos.cc
+//
+// Copyright (c) 1996-2003 Bryce W. Harrington  [bryce at osdl dot org]
+//
+//-----------------------------------------------------------------------
+// License:  This code may be used by anyone for any purpose
+//           so long as the copyright notices and this license
+//           statement remains attached.
+//-----------------------------------------------------------------------
+//
+// string ftos(double val[, char mode[, int sigfig[, int precision[, int options]]]])
+//
+//  DESCRIPTION
+//    This routine is intended to replace the typical use of sprintf for
+//    converting floating point numbers into strings.
+//
+//    To one-up sprintf, an additional mode was created - 'h' mode -
+//    which produces numbers in 'engineering notation' - exponents are
+//    always shown in multiples of 3.  To non-engineers this mode is
+//    probably irrelevant, but for engineers (and scientists) it is SOP.
+//
+//    One other new feature is an option to use 'x10^' instead of the
+//    conventional 'E' for exponental notation.  This is entirely for
+//    aesthetics since numbers in the 'x10^' form cannot be used as
+//    inputs for most programs.
+//
+//    For most cases, the routine can simply be used with the defaults
+//    and acceptable results will be produced.  No fill zeros or trailing
+//    zeros are shown, and exponential notation is only used for numbers
+//    greater than 1e6 or less than 1e-3.
+//
+//    The one area where sprintf may surpass this routine is in width control.
+//    No provisions are made in this routine to restrict a number to a
+//    certain number of digits (thus allowing the number to be constrained
+//    to an 8 space column, for instance.)  Along with this, it does not
+//    support pre-padding a number with zeros (e.g., '5' -> '0005') and will
+//    not post-pad a number with spaces (i.e., allow left-justification.)
+//
+//    If width control is this important, then the user will probably want to
+//    use the stdio routines, which really is well suited for outputting
+//    columns of data with a brief amount of code.
+//
+//  PARAMETERS
+//    val        - number to be converted
+//    mode       - can be one of four possible values.  Default is 'g'
+//
+//                 e: Produces numbers in scientific notation.  One digit
+//                    is shown on the left side of the decimal, the rest
+//                    on the right, and the exponential is always shown.
+//                    EXAMPLE:  1.04e-4
+//
+//                 f: Produces numbers with fixed format.  Number is shown
+//                    exact, with no exponent.
+//                    EXAMPLE:  0.000104
+//
+//                 g: If val is greater than 1e6 or less than 1e-3 it will
+//                    be shown in 'e' format, otherwise 'f' format will be
+//                    used.
+//
+//                 h: Produces numbers in engineering format.  Result is
+//                    identical to 'f' format for numbers between 1 and
+//                    1e3, otherwise, the number is shown such that it
+//                    always begins with a nonzero digit on the left side
+//                    (unless number equals zero), and the exponential is
+//                    a multiple of 3.
+//                    EXAMPLE:  104e-6
+//
+//                 If the mode is expressed as a capital letter (e.g., 'F')
+//                 then the exponential part of the number will also be
+//                 capitalized (e.g., '1E6' or '1X10^6'.)
+//
+//    sigfig     - the number of significant figures.  These are the digits
+//                 that are "retained".  For example, the following numbers
+//                 all have four sigfigs:
+//                    1234       12.34      0.0001234       1.234e-10
+//                 the last digit shown will be rounded in the standard
+//                 manner (down if the next digit is less than 5, up otherwise.)
+//
+//    precision  - the number of digits to show to the right of the decimal.
+//                 For example, all of the following numbers have precisions
+//                 of 2:
+//                    1234.00     12.34     0.00     1.23e-10   123.40e-12
+//
+//    options    - several options are allowed to control the look of the
+//                 output.
+//
+//               FORCE_DECIMAL - require the decimal point to be shown for
+//                 numbers that do not have any fractional digits (or that
+//                 have a precision set to zero)
+//                 EXAMPLE:  1.e6
+//               FORCE_EXP_ZERO - pad the 10's zero in exponent if necessary
+//                 EXAMPLE:  1e06
+//               FORCE_HUNDRED_EXP_ZERO - pad the 100's zero in exponent if
+//                 necessary.  Also pads 10's zero in exponent if necessary.
+//                 EXAMPLE:  1e006
+//               FORCE_EXP_PLUS - show the '+' in the exponent if exponent
+//                 is used.
+//                 EXAMPLE:  1e+6
+//               FORCE_EXP - force the output to display the exponent
+//                 EXAMPLE:  0e0
+//               FORCE_X10 - use x10^ instead of E
+//                 EXAMPLE:  1x10^6
+//               FORCE_PLUS - force output of the '+' for positive numbers
+//                 EXAMPLE:  +1e6
+//
+//                 Options can be combined using the usual OR method.  For
+//                 example,
+//
+//                 ftos(123.456, 'f', -1, -1, FORCE_PLUS | FORCE_X10 | FORCE_EXP)
+//
+//                 gives "+123.456x10^0"
+//
+//  RETURN VALUE
+//    The string representation of the number is returned from the routine.
+//    The ANSI C++ Standard "string" class was used for several important
+//    reasons.  First, because the string class manages it's own space, the
+//    ftos routine does not need to concern itself with writing to unallocated
+//    areas of memory or with handling memory reallocation internally.  Second,
+//    it allows return of an object, not a pointer to an object; this may not
+//    be as efficient, but it is cleaner and safer than the alternative.  Third,
+//    the routine's return value can be directly assigned to a variable, i.e.
+//        string var = ftos(3.1415);
+//    which makes code much easier to comprehend and modify.
+//
+//    Internally, the ftos routine uses fairly typical string operators (=, +=,
+//    +, etc.) which pretty much any other flavor of string class will define as
+//    well.  Thus if one does not have access to the ANSI C++ Standard string
+//    class, the user can substitute another with little difficulty.  (If the
+//    alternate class is not named "string" then redefine "string" to whatever
+//    you wish to use.  For example,
+//        #define string CString
+//
+// November 1996 - Bryce Harrington
+//    Created ftoa and ftos
+//
+// December 1996 - Bryce Harrington
+//    Added engineering notation mode, added sigfig capability, added
+//    significant debug code, added options, thoroughly debugged and
+//    tested the code.
+//
+//
+// June 1999 - Bryce Harrington
+//    Modified to run on Linux for WorldForge
+//
+// March 2003 - Bryce Harrington
+//    Removed DTAG() macros - use of fprintf(stderr,...) instead
+//    Broke out round/itos/ftos into separate files
+//    Removed curses bits
+//
+/////////////////////////////////////////////////////////////////////// */
+
+#include <string>
+
+// This is the routine used for converting a floating point into a string
+// This may be included in stdlib.h on some systems and may conflict.
+// Let me know your system & etc. so I can properly #ifdef this, but
+// try commenting the following four lines out if you run into conflicts.
+// extern "C" {
+// char*
+// ecvt (double val, size_t ndigit, int *decpt, int *sign);
+// }
+
+using namespace std;
+
+#ifndef HAS_ECVT
+#include <cstdio>
+#include <glib.h>
+#endif
+
+
+#include "ftos.h"
+
+#include <iostream>
+
+// This routine counts from the end of a string like '10229000' to find the index
+// of the first non-'0' character (5 would be returned for the above number.)
+int countDigs(char *p)
+{
+    int length =0;
+    while (*(p+length)!='\0') length++;               // Count total length
+    while (length>0 && *(p+length-1)=='0') length--;  // Scan backwards for a non-'0'
+    return length;
+}
+
+// This routine determines how many digits make up the left hand
+// side of the number if the abs value of the number is greater than 1, or the
+// digits that make up the right hand side if the abs value of the number
+// is between 0 and 1.  Returns 1 if v==0.  Return value is positive for numbers
+// greater than or equal to 1, negative for numbers less than 0.1, and zero for
+// numbers between 0.1 and 1.
+int countLhsDigits(double v)
+{
+    if (v<0) v = -v;                   // Take abs value
+    else if (v==0) return 1;           // Special case if v==0
+
+    int n=0;
+    for (; v<0.1; v*=10)               // Count digits on right hand side (l.t. 0.1)
+        { n--; }
+    for (; v>=1; v/=10)                // Count digits on left hand side (g.e. 1.0)
+        { n++; }
+    return n;
+}
+
+// This is the routine that does the work of converting the number into a string.
+string ftos(double val, char mode, int sigfig, int precision, int options)
+{
+    // Parse the options to a more usable form
+    // These options allow the user to control some of the ornaments on the
+    // number that is output.  By default they are all false.  Turning them
+    // on helps to "fix" the format of the number so it lines up in columns
+    // better.
+    // - require the decimal point to be shown for numbers that do not have
+    //   any fractional digits (or that have a precision set to zero
+    bool forceDecimal = (options & FORCE_DECIMAL);
+    // - show the 10's and 100's zero in exponent
+    bool forceExpZero = (options & FORCE_EXP_ZERO);
+    bool forceHundredExpZero = (options & FORCE_HUNDRED_EXP_ZERO);
+    // - show the '+' in the exponent if exponent is used
+    bool forceExpPlus = (options & FORCE_EXP_PLUS);
+    // - force the output to display the exponent
+    bool forceExponent = (options & FORCE_EXP);
+    // - use x10^ instead of E
+    bool forcex10 = (options & FORCE_X10);
+    // - force output of the '+' for positive numbers
+    bool forcePlus = (options & FORCE_PLUS);
+
+#ifdef DEBUG
+    fprintf(stderr, "Options: ");
+    fprintf(stderr, "  %4s = %s ", "x10", (forcex10            ? "on" : "off" ));
+    fprintf(stderr, "  %4s = %s ", ".",   (forceDecimal        ? "on" : "off" ));
+    fprintf(stderr, "  %4s = %s ", "e0",  (forceExpZero        ? "on" : "off" ));
+    fprintf(stderr, "  %4s = %s ", "e00", (forceHundredExpZero ? "on" : "off" ));
+    fprintf(stderr, "  %4s = %s ", "e+",  (forceExpPlus        ? "on" : "off" ));
+    fprintf(stderr, "  %4s = %s ", "e",   (forceExponent       ? "on" : "off" ));
+    fprintf(stderr, "  %4s = %s \n", "+#",  (forcePlus           ? "on" : "off" ));
+#endif
+
+    // - exponent usage
+    bool useExponent = false;
+
+    // Determine the case for the 'e' (if used)
+    char E = (forcex10)? 'x' : 'e';
+    if (g_ascii_isupper(mode)) {
+        E = g_ascii_toupper(E);
+        mode = g_ascii_tolower(mode);
+    }
+
+    // Determine how many decimals we're interested in
+    int L = countLhsDigits(val);
+
+#ifdef DEBUG
+    fprintf(stderr, "*** L is %s\n", itos(L).c_str());
+#endif
+
+    int count = 0;
+    if (sigfig==0)                     // bad input - don't want any sigfigs??!!
+        return "";
+    else if (precision>=0) {           // Use fixed number of decimal places
+        count = precision;
+        if (mode == 'e') count += 1;
+        else if (mode == 'f') count += L;
+        else if (mode == 'g') count += (L>6 || L<-3)? 1 : L;
+        else if (mode == 'h') count += (L>0)? ((L-1)%3+1) : (L%3+3);
+        if (sigfig>0) count = (sigfig > count)? count : sigfig;  // Use sigfig # if it means more decimal places
+    }
+    else if (sigfig>0)                 // Just use sigfigs
+        count = sigfig;
+    else                               // prec < 0 and sigfig < 0
+        count = 10;
+#ifdef DEBUG
+    fprintf(stderr, "*** count is %s\n", itos(count).c_str());
+#endif
+
+    // Get number's string rep, sign, and exponent
+    int sign = 0;
+    int decimal=0;
+
+#ifdef HAS_ECVT
+    char *p = ecvt(val, count, &decimal, &sign);
+#else
+    char *p = (char *) g_strdup_printf("%.0f", val);
+    // asprintf(&p, "%.0f", val);
+#endif
+
+#ifdef DEBUG
+    fprintf(stderr, "*** string rep is %s\n", p);
+    fprintf(stderr, "*** decimal is %s\n", itos(decimal).c_str());
+    fprintf(stderr, "*** sign is %s\n", itos(sign).c_str());
+#endif
+
+    // Count the number of relevant digits in the resultant number
+    int dig = countDigs(p);
+    if (dig < sigfig) dig = sigfig;
+
+#ifdef DEBUG
+    fprintf(stderr, "*** digs is %s\n", itos(dig).c_str());
+#endif
+
+    // Determine number of digits to put on left side of the decimal point
+    int lhs=0;
+    // For 'g' mode, decide whether to use 'e' or 'f' format.
+    if (mode=='g') mode = (decimal>6 || decimal<-3)? 'e' : 'f';
+    switch (mode) {
+        case 'e':
+            lhs = 1;                   // only need one char on left side
+            useExponent = true;        // force exponent use
+            break;
+
+        case 'f':
+            lhs = (decimal<1)? 1 : decimal;
+                                       // use one char on left for num < 1,
+                                       // otherwise, use the number of decimal places.
+            useExponent = false;       // don't want exponent for 'f' format
+            break;
+
+        case 'h':
+            if (val==0.0)              // special case for if value is zero exactly.
+                lhs = 0;               // this prevents code from returning '000.0'
+            else
+                lhs = (decimal<=0)? (decimal)%3 + 3  :  (decimal-1)%3+1;
+            useExponent = !(lhs==decimal);   // only use exponent if we really need it
+            break;
+
+        default:
+            return "**bad mode**";
+    }
+
+#ifdef DEBUG
+    fprintf(stderr, "*** lhs is %s\n", itos(lhs).c_str());
+#endif
+
+    // Figure out the number of digits to show in the right hand side
+    int rhs=0;
+    if (precision>=0)
+        rhs = precision;
+    else if (val == 0.0)
+        rhs = 0;
+    else if (useExponent || decimal>0)
+        rhs = dig-lhs;
+    else
+        rhs = dig-decimal;
+
+    // can't use a negative rhs value, so turn it to zero if that is the case
+    if (rhs<0) rhs = 0;
+
+#ifdef DEBUG
+    fprintf(stderr, "*** rhs is", itos(rhs).c_str());
+#endif
+
+    // Determine the exponent
+    int exponent = decimal - lhs;
+    if (val==0.0) exponent=0;          // prevent zero from getting an exponent
+#ifdef DEBUG
+    fprintf(stderr, "*** exponent is %s\n", itos(exponent).c_str());
+#endif
+
+    string ascii;
+
+    // output the sign
+    if (sign) ascii += "-";
+    else if (forcePlus) ascii += "+";
+
+    // output the left hand side
+    if (!useExponent && decimal<=0)    // if fraction, put the 0 out front
+        ascii += '0';
+    else                               // is either exponential or >= 1, so write the lhs
+        for (; lhs>0; lhs--)
+            ascii += (*p)? *p++ : int('0'); // now fill in the numbers before decimal
+
+#ifdef DEBUG
+    fprintf(stderr, "*** ascii + sign + lhs is %s\n", ascii.c_str());
+#endif
+
+    // output the decimal point
+    if (forceDecimal || rhs>0)
+        ascii += '.';
+
+    // output the right hand side
+    if (!useExponent && rhs>0)         // first fill in zeros after dp and before numbers
+        while (decimal++ <0 && rhs-->0)
+            ascii += '0';
+    for (; rhs>0 ; rhs--)              // now fill in the numbers after decimal
+        ascii += (*p)? *p++ : int('0');
+
+#ifdef DEBUG
+    fprintf(stderr, "*** ascii + . + rhs is %s\n", ascii.c_str());
+#endif
+
+    if (forceExponent || useExponent)  // output the entire exponent if required
+    {
+        ascii += E;                    // output the E or X
+        if (forcex10) ascii += "10^";  // if using 'x10^' format, output the '10^' part
+
+        // output the exponent's sign
+        if (exponent < 0) {            // Negative exponent
+            exponent = -exponent;      // make exponent positive if needed
+            ascii += '-';              // output negative sign
+        }
+        else if (forceExpPlus)         // We only want the '+' if it is asked for explicitly
+            ascii += '+';
+
+        // output the exponent
+        if (forceHundredExpZero || exponent >= 100)
+            ascii += ( (exponent/100) % 10 + '0' );
+        if (forceHundredExpZero || forceExpZero || exponent >= 10)
+            ascii += ( (exponent/10) % 10 + '0' );
+        ascii += ( exponent % 10 + '0' );
+
+#ifdef DEBUG
+        fprintf(stderr, "*** ascii + exp is %s\n", ascii.c_str());
+#endif
+    }
+
+#ifdef DEBUG
+    fprintf(stderr, "*** End of ftos with ascii = ", ascii.c_str());
+#endif
+    /* finally, we can return */
+    return ascii;
+}
+
+#ifdef TESTFTOS
+
+int main()
+{
+  cout << "Normal (g): " << endl;
+  cout << "1.0   = " << ftos(1.0)   << endl;
+  cout << "42    = " << ftos(42)    << endl;
+  cout << "3.141 = " << ftos(3.141) << endl;
+  cout << "0.01  = " << ftos(0.01)  << endl;
+  cout << "1.0e7 = " << ftos(1.0e7) << endl;
+  cout << endl;
+
+  cout << "Scientific (e): " << endl;
+  cout << "1.0   = " << ftos(1.0,   'e')   << endl;
+  cout << "42    = " << ftos(42,    'e')   << endl;
+  cout << "3.141 = " << ftos(3.141, 'e') << endl;
+  cout << "0.01  = " << ftos(0.01,  'e')  << endl;
+  cout << "1.0e7 = " << ftos(1.0e7, 'e') << endl;
+  cout << endl;
+
+  cout << "Fixed (f): " << endl;
+  cout << "1.0   = " << ftos(1.0,   'f')   << endl;
+  cout << "42    = " << ftos(42,    'f')   << endl;
+  cout << "3.141 = " << ftos(3.141, 'f') << endl;
+  cout << "0.01  = " << ftos(0.01,  'f')  << endl;
+  cout << "1.0e7 = " << ftos(1.0e7, 'f') << endl;
+  cout << endl;
+
+  cout << "Engineering (h): " << endl;
+  cout << "1.0   = " << ftos(1.0,   'h')   << endl;
+  cout << "42    = " << ftos(42,    'h')    << endl;
+  cout << "3.141 = " << ftos(3.141, 'h') << endl;
+  cout << "0.01  = " << ftos(0.01,  'h')  << endl;
+  cout << "1.0e7 = " << ftos(1.0e7, 'h') << endl;
+  cout << endl;
+
+  cout << "Sigfigs: " << endl;
+  cout << "2 sf = " << ftos(1234, 'g', 2) << "  "
+       << ftos(12.34,     'g', 2) << "  "
+       << ftos(0,         'g', 2) << "  "
+       << ftos(123.4e-11, 'g', 2) << endl;
+  cout << "4 sf = " << ftos(1234, 'g', 4) << "  "
+       << ftos(12.34,     'g', 4) << "  "
+       << ftos(0,         'g', 4) << "  "
+       << ftos(123.4e-11, 'g', 4) << endl;
+  cout << "8 sf = " << ftos(1234, 'g', 8) << "  "
+       << ftos(12.34,     'g', 8) << "  "
+       << ftos(0,         'g', 8) << "  "
+       << ftos(123.4e-11, 'g', 8) << endl;
+  cout << endl;
+
+  cout << "x10 mode: " << endl;
+  cout << "1234 = " << ftos(1234, 'e', 4, -1, FORCE_X10 | FORCE_EXP) << endl;
+  cout << "1.01e10 = " << ftos(1.01e10, 'h', -1, -1, FORCE_X10 | FORCE_EXP) << endl;
+  cout << endl;
+
+  cout << "itos tests..." << endl;
+  cout << "42   = " << itos(42) << endl;
+  cout << endl;
+
+  return 0;
+}
+
+#endif // TESTFTOS