2018-08-30 HaO Implemented GS separator for Datamatrix (--gssep option). Ticket #139

backend/dmatrix.c

@@ -435,12 +435,14 @@ static int look_ahead_test(const unsigned char inputData[], const size_t sourcel
                     edf_count += 13.0F; // (p)(3) > Value changed from ISO
                 }
             }
-            if ((gs1 == 1) && (inputData[sp] == '[')) {
+            if (gs1 && (inputData[sp] == '[')) {
+                /* fnc1 and gs have the same weight of 13.0f */
                 edf_count += 13.0F; //  > Value changed from ISO
             }
 
             /* base 256 ... step (q) */
             if ((gs1 == 1) && (inputData[sp] == '[')) {
+                /* FNC1 separator */
                 b256_count += 4.0F; // (q)(1)
             } else {
                 b256_count += 1.0F; // (q)(2)
@@ -549,8 +551,13 @@ static int dm200encode(struct zint_symbol *symbol, const unsigned char source[],
     current_mode = DM_ASCII;
     next_mode = DM_ASCII;
 
+    /* gs1 flag values: 0: no gs1, 1: gs1 with FNC1 serparator, 2: GS separator */
     if (symbol->input_mode == GS1_MODE) {
-        gs1 = 1;
+        if (symbol->output_options & GS1_GS_SEPARATOR) {
+            gs1 = 2;
+        } else {
+            gs1 = 1;
+        }
     } else {
         gs1 = 0;
     }
@@ -684,8 +691,13 @@ static int dm200encode(struct zint_symbol *symbol, const unsigned char source[],
                         strcat(binary, "  ");
                     } else {
                         if (gs1 && (source[sp] == '[')) {
-                            target[tp] = 232; /* FNC1 */
-                            if (debug) printf("FN1 ");
+                            if (gs1==2) {
+                                target[tp] = 29+1; /* GS */
+                                if (debug) printf("GS ");
+                            } else {
+                                target[tp] = 232; /* FNC1 */
+                                if (debug) printf("FN1 ");
+                            }
                         } else {
                             target[tp] = source[sp] + 1;
                             if (debug) printf("A%02X ", target[tp] - 1);
@@ -728,8 +740,13 @@ static int dm200encode(struct zint_symbol *symbol, const unsigned char source[],
                 }
 
                 if (gs1 && (source[sp] == '[')) {
-                    shift_set = 2;
-                    value = 27; /* FNC1 */
+                    if (gs1 == 2) {
+                        shift_set = c40_shift[29];
+                        value = c40_value[29]; /* GS */
+                    } else {
+                        shift_set = 2;
+                        value = 27; /* FNC1 */
+                    }
                 }
 
                 if (shift_set != 0) {
@@ -791,8 +808,13 @@ static int dm200encode(struct zint_symbol *symbol, const unsigned char source[],
                 }
 
                 if (gs1 && (source[sp] == '[')) {
-                    shift_set = 2;
-                    value = 27; /* FNC1 */
+                    if (gs1 == 2) {
+                        shift_set = text_shift[29];
+                        value = text_value[29]; /* GS */
+                    } else {
+                        shift_set = 2;
+                        value = 27; /* FNC1 */
+                    }
                 }
 
                 if (shift_set != 0) {

backend/zint.h

@@ -253,6 +253,7 @@ extern "C" {
 #define BOLD_TEXT               64
 #define CMYK_COLOUR             128
 #define BARCODE_DOTTY_MODE      256
+#define GS1_GS_SEPARATOR        512
 
 // Input data types
 #define DATA_MODE	0

docs/manual.txt

@@ -418,7 +418,7 @@ GS1 data can be encoded in a number of symbologies. Application identifiers
 should be enclosed in [square brackets] followed by the data to be encoded (see 
 5.1.12.3). To encode GS1 data use the --gs1 option. GS1 mode is assumed (and 
 doesn't need to be set) for EAN-128, DataBar and Composite symbologies but is 
-also available for Code 16k, Data Matrix, Aztec Code, DotCode and QR Code. 
+also available for Code 16k, Data Matrix, Aztec Code, DotCode and QR Code.
 
 HIBC data may also be encoded in the symbologies Code 39, Code128, Codablock-F,
 Datamatrix, QR-Code, PDF417 and Aztec-Code. Within this mode, the leading '+' and the
@@ -1052,6 +1052,7 @@ BOLD_TEXT           |  Embolden the human readable text.
 CMYK_COLOUR         |  Select the CMYK colour space option for encapsulated
                     |      PostScript files.
 BARCODE_DOTTY_MODE  |  Plot a matrix symbol using dots rather than squares.
+GS1_GS_SEPARATOR    |  Use GS instead FNC1 as GS1 separator.
 --------------------------------------------------------------------------------
 
 5.9 Setting the Input Mode
@@ -1847,6 +1848,10 @@ Input  |  Symbol Size
 DMRE symbol sizes may be activated in automatic size mode using the option 
 --dmre or by the API option_3 = DM_DMRE
 
+GS1 symbology may use FNC1 (prefered) or GS as separator.
+Use the option --gssep to change to GS or use the API
+output_options+=GS1_GS_SEPARATOR
+
 6.6.2 QR Code (ISO 18004)
 -------------------------
 Also known as Quick Response Code this symbology was developed by Denso. Four