[vte/wip/egmont/bidi: 22/91] add new files

[Egmont Koblinger <egmontkob src gnome org>]

commit 05ad4782a694f8ec5762016856ad428127ca8054
Author: Egmont Koblinger <egmont gmail com>
Date:   Tue Aug 21 13:32:33 2018 +0200

    add new files

 src/bidi.cc | 119 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 src/bidi.hh |  31 ++++++++++++++++
 2 files changed, 150 insertions(+)
---
diff --git a/src/bidi.cc b/src/bidi.cc
new file mode 100644
index 00000000..c79809e2
--- /dev/null
+++ b/src/bidi.cc
@@ -0,0 +1,119 @@
+/*
+ * Copyright © 2018 Egmont Koblinger
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include <config.h>
+
+#ifdef WITH_FRIBIDI
+#include <fribidi.h>
+#endif
+
+#include "bidi.hh"
+#include "debug.h"
+#include "vteinternal.hh"
+
+#ifdef WITH_FRIBIDI
+
+FriBidiChar str[1000];
+FriBidiStrIndex L_to_V[1000];
+FriBidiStrIndex V_to_L[1000];
+
+static void bidi_shuffle_explicit (int width, gboolean rtl)
+{
+        int i;
+
+        if (rtl) {
+                for (i = 0; i < width; i++) {
+                        L_to_V[i] = V_to_L[i] = width - 1 - i;
+                }              
+        } else {
+                for (i = 0; i < width; i++) {
+                        L_to_V[i] = V_to_L[i] = i;
+                }              
+        }
+}
+
+void bidi_shuffle (const VteRowData *rowdata, int width)
+{
+        int i;
+        FriBidiParType pbase_dir;
+
+        if (rowdata == NULL) {  // FIXME make sure it doesn't happen
+                bidi_shuffle_explicit (width, FALSE);
+                return;
+        }
+
+        if (!(rowdata->attr.bidi_flags & VTE_BIDI_IMPLICIT)) {
+                bidi_shuffle_explicit (width, rowdata->attr.bidi_flags & VTE_BIDI_RTL);
+                return;
+        }
+
+        for (i = 0; i < rowdata->len && i < width; i++) {
+                if (rowdata->cells[i].c == 0) break;
+                // FIXME is it okay to run the BiDi algorithm without the combining accents?
+                str[i] = _vte_unistr_get_base(rowdata->cells[i].c);
+        }
+
+        pbase_dir = (rowdata->attr.bidi_flags & VTE_BIDI_AUTO) 
+                    ? FRIBIDI_PAR_ON
+                    : (rowdata->attr.bidi_flags & VTE_BIDI_RTL) ? FRIBIDI_PAR_RTL : FRIBIDI_PAR_LTR;
+
+        fribidi_log2vis (str, i, &pbase_dir, NULL, L_to_V, V_to_L, NULL);
+
+        if (pbase_dir == FRIBIDI_PAR_ON) {
+                pbase_dir = (rowdata->attr.bidi_flags & VTE_BIDI_RTL) ? FRIBIDI_PAR_RTL : FRIBIDI_PAR_LTR;
+        }
+
+        if (pbase_dir == FRIBIDI_PAR_RTL || pbase_dir == FRIBIDI_PAR_WRTL) {
+                if (i < width) {
+                        /* shift to the right */
+                        int shift = width - i;
+                        for (i--; i >= 0; i--) {
+                                L_to_V[i] += shift;
+                                V_to_L[i + shift] = V_to_L[i];
+                        }
+                        for (i = 0; i < shift; i++) {
+                                L_to_V[width - 1 - i] = i;
+                                V_to_L[i] = width - 1 - i;
+                        }
+                }
+        } else {
+                for (; i < width; i++) {
+                        L_to_V[i] = V_to_L[i] = i;
+                }
+        }
+}
+
+#else /* WITH_FRIBIDI */
+
+void bidi_shuffle (const VteRowData *rowdata, int width) {
+        if (rowdata == NULL) {  // FIXME make sure it doesn't happen
+                bidi_shuffle_explicit (width, FALSE);
+        } else {
+                bidi_shuffle_explicit (width, rowdata->attr.bidi_flags & VTE_BIDI_RTL);
+        }
+}
+
+#endif /* WITH_FRIBIDI */
+
+int log2vis (int log) {
+        return L_to_V[log];
+}
+
+int vis2log (int vis) {
+        return V_to_L[vis];
+}
diff --git a/src/bidi.hh b/src/bidi.hh
new file mode 100644
index 00000000..b712caef
--- /dev/null
+++ b/src/bidi.hh
@@ -0,0 +1,31 @@
+/*
+ * Copyright © 2018 Egmont Koblinger
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#pragma once
+
+#include <glib.h>
+
+#include "vterowdata.hh"
+
+G_BEGIN_DECLS
+
+void bidi_shuffle (const VteRowData *rowdata, int width);
+int log2vis (int log);
+int vis2log (int vis);
+
+G_END_DECLS