generalize the lam-alef case

3 files changed, 104 insertions, 65 deletions

diff --git a/arabic_test.txt b/arabic_test.txt
index a5d431d..2d49a48 100644
--- a/arabic_test.txt
+++ b/arabic_test.txt
@@ -1 +1,12 @@
-اعطني الناي و غني فالغناﺀ سر الوجود    فأنين الناي يبقئ بعد ان يفنئ الوجود 
+أعطني الناي وغني فالغنا سر الوجود
+وأنين الناي يبقى بعد أن يفنى الوجود
+هل إتخذت الغاب مثلي منزلاً دون القصور
+فتتبعت السواقي وتسلقت الصخور
+هل تحممت بعطر وتنشفت بنور
+وشربت الفجر خمراً فى كؤوس من أثير
+هل جلست العصر مثلي بين جفنات العنب
+والعناقيد تدلت كثريات الذهب
+هل فرشت العشب ليلاً وتلحفت الفضاء
+زاهداً في ما سيأتي ناسياً ما قد مضى
+أعطني الناي وغني وانسى داء ودواء
+إنما الناس سطورٌ كتبت لكن بماء
diff --git a/arabtype.c b/arabtype.c
index 12c6b43..0136bc5 100644
--- a/arabtype.c
+++ b/arabtype.c
@@ -4,6 +4,7 @@
 */
 
 #include <stdbool.h>
+#include <stdio.h>
 #include "utf8.h"
 #include "arabtype.h"
 
@@ -21,74 +22,88 @@
 // 2: beginning form	(if 0, it's a cutting type)
 // 3: middle form
 //
-typedef uint32_t char_form[4];
+typedef uint32_t char_form_t[4];
+typedef char_form_t	all_form_t[2];
 
-char_form	arabic_forms_b[]	=
-{
-	{0xFE80, 0xFE80, 0, 0},			// hamza	(0)
-	{0xFE81, 0xFE82, 0, 0},			// 2alif madda	(1)
-	{0xFE83, 0xFE84, 0, 0},			// 2alif hamza	(2)
-	{0xFE85, 0xFE86, 0, 0},			// waw hamza	(3)
-	{0xFE87, 0xFE88, 0, 0},			// 2alif hamza maksoura	(4)
-	{0xFE89, 0xFE8A, 0xFE8B, 0xFE8C},	// 2alif maqsoura hamza	(5)
-	{0xFE8D, 0xFE8E, 0, 0},			// 2alif	(6)
-	{0xFE8F, 0xFE90, 0xFE91, 0xFE92},	// ba2		(7)
-	{0xFE93, 0xFE94, 0, 0},			// ta2 marbouta	(8)
-	{0xFE95, 0xFE96, 0xFE97, 0xFE98},	// ta2		(9)
-	{0xFE99, 0xFE9A, 0xFE9B, 0xFE9C},	// tha2		(10)
-	{0xFE9D, 0xFE9E, 0xFE9F, 0xFEA0},	// jim		(11)
-	{0xFEA1, 0xFEA2, 0xFEA3, 0xFEA4},	// 7a2		(12)
-	{0xFEA5, 0xFEA6, 0xFEA7, 0xFEA8},	// kha2		(13)
-	{0xFEA9, 0xFEAA, 0, 0},			// dal		(14)
-	{0xFEAB, 0xFEAC, 0, 0},			// dhal		(15)
-	{0xFEAD, 0xFEAE, 0, 0},			// ra2		(16)
-	{0xFEAF, 0xFEB0, 0, 0},			// zayn		(17)
-	{0xFEB1, 0xFEB2, 0xFEB3, 0xFEB4},	// syn		(18)
-	{0xFEB5, 0xFEB6, 0xFEB7, 0xFEB8},	// shin		(19)
-	{0xFEB9, 0xFEBA, 0xFEBB, 0xFEBC},	// sad		(20)
-	{0xFEBD, 0xFEBE, 0xFEBF, 0xFEC0},	// dad		(21)
-	{0xFEC1, 0xFEC2, 0xFEC3, 0xFEC4},	// tah		(22)
-	{0xFEC5, 0xFEC6, 0xFEC7, 0xFEC8},	// thah		(23)
-	{0xFEC9, 0xFECA, 0xFECB, 0xFECC},	// 3ayn		(24)
-	{0xFECD, 0xFECE, 0xFECF, 0xFED0},	// ghayn	(25)
-	{0, 0, 0, 0},				//		(26)
-	{0, 0, 0, 0},				//		(27)
-	{0, 0, 0, 0},				//		(28)
-	{0, 0, 0, 0},				//		(29)
-	{0, 0, 0, 0},				//		(30)
-	{0x640, 0x640, 0x640, 0x640},		// wasla	(31)
-	{0xFED1, 0xFED2, 0xFED3, 0xFED4},	// fa2		(32)
-	{0xFED5, 0xFED6, 0xFED7, 0xFED8},	// qaf		(33)
-	{0xFED9, 0xFEDA, 0xFEDB, 0xFEDC},	// kaf		(34)
-	{0xFEDD, 0xFEDE, 0xFEDF, 0xFEE0},	// lam		(35)
-	{0xFEE1, 0xFEE2, 0xFEE3, 0xFEE4},	// mim		(36)
-	{0xFEE5, 0xFEE6, 0xFEE7, 0xFEE8},	// noon		(37)
-	{0xFEE9, 0xFEEA, 0xFEEB, 0xFEEC},	// ha2		(38)
-	{0xFEED, 0xFEEE, 0, 0},			// waw		(39)
-	{0xFEFF, 0xFEF0, 0, 0},			// 2alif maksoura	(40)
-	{0xFEF1, 0xFEF2, 0xFEF3, 0xFEF4}	// ya2		(41)
+static all_form_t arabic_forms_b[]	= {
+	{ {0xFE80, 0xFE80,      0,      0}, {0, 0, 0, 0} },	// hamza	(0)
+	{ {0xFE81, 0xFE82,      0,      0}, {0, 0, 0xFEF5, 0xFEF6} },	// 2alif madda	(1)
+	{ {0xFE83, 0xFE84,      0,      0}, {0, 0, 0xFEF7, 0xFEF8} },	// 2alif hamza	(2)
+	{ {0xFE85, 0xFE86,      0,      0}, {0, 0, 0, 0} },	// waw hamza	(3)
+	{ {0xFE87, 0xFE88,      0,      0}, {0, 0, 0xFEF9, 0xFEFA} },	// 2alif hamza maksoura	(4)
+	{ {0xFE89, 0xFE8A, 0xFE8B, 0xFE8C}, {0, 0, 0, 0} },	// 2alif maqsoura hamza	(5)
+	{ {0xFE8D, 0xFE8E,      0,      0}, {0, 0, 0xFEFB, 0xFEFC} },	// 2alif	(6)
+	{ {0xFE8F, 0xFE90, 0xFE91, 0xFE92}, {0, 0, 0, 0} },	// ba2		(7)
+	{ {0xFE93, 0xFE94,      0,      0}, {0, 0, 0, 0} },	// ta2 marbouta	(8)
+	{ {0xFE95, 0xFE96, 0xFE97, 0xFE98}, {0, 0, 0, 0} },	// ta2		(9)
+	{ {0xFE99, 0xFE9A, 0xFE9B, 0xFE9C}, {0, 0, 0, 0} },	// tha2		(10)
+	{ {0xFE9D, 0xFE9E, 0xFE9F, 0xFEA0}, {0, 0, 0, 0} },	// jim		(11)
+	{ {0xFEA1, 0xFEA2, 0xFEA3, 0xFEA4}, {0, 0, 0, 0} },	// 7a2		(12)
+	{ {0xFEA5, 0xFEA6, 0xFEA7, 0xFEA8}, {0, 0, 0, 0} },	// kha2		(13)
+	{ {0xFEA9, 0xFEAA,      0,      0}, {0, 0, 0, 0} },	// dal		(14)
+	{ {0xFEAB, 0xFEAC,      0,      0}, {0, 0, 0, 0} },	// dhal		(15)
+	{ {0xFEAD, 0xFEAE,      0,      0}, {0, 0, 0, 0} },	// ra2		(16)
+	{ {0xFEAF, 0xFEB0,      0,      0}, {0, 0, 0, 0} },	// zayn		(17)
+	{ {0xFEB1, 0xFEB2, 0xFEB3, 0xFEB4}, {0, 0, 0, 0} },	// syn		(18)
+	{ {0xFEB5, 0xFEB6, 0xFEB7, 0xFEB8}, {0, 0, 0, 0} },	// shin		(19)
+	{ {0xFEB9, 0xFEBA, 0xFEBB, 0xFEBC}, {0, 0, 0, 0} },	// sad		(20)
+	{ {0xFEBD, 0xFEBE, 0xFEBF, 0xFEC0}, {0, 0, 0, 0} },	// dad		(21)
+	{ {0xFEC1, 0xFEC2, 0xFEC3, 0xFEC4}, {0, 0, 0, 0} },	// tah		(22)
+	{ {0xFEC5, 0xFEC6, 0xFEC7, 0xFEC8}, {0, 0, 0, 0} },	// thah		(23)
+	{ {0xFEC9, 0xFECA, 0xFECB, 0xFECC}, {0, 0, 0, 0} },	// 3ayn		(24)
+	{ {0xFECD, 0xFECE, 0xFECF, 0xFED0}, {0, 0, 0, 0} },	// ghayn	(25)
+	{ {     0,      0,      0,      0}, {0, 0, 0, 0} },	//		(26)
+	{ {     0,      0,      0,      0}, {0, 0, 0, 0} },	//		(27)
+	{ {     0,      0,      0,      0}, {0, 0, 0, 0} },	//		(28)
+	{ {     0,      0,      0,      0}, {0, 0, 0, 0} },	//		(29)
+	{ {     0,      0,      0,      0}, {0, 0, 0, 0} },	//		(30)
+	{ { 0x640,  0x640,  0x640,  0x640}, {0, 0, 0, 0} },	// wasla	(31)
+	{ {0xFED1, 0xFED2, 0xFED3, 0xFED4}, {0, 0, 0, 0} },	// fa2		(32)
+	{ {0xFED5, 0xFED6, 0xFED7, 0xFED8}, {0, 0, 0, 0} },	// qaf		(33)
+	{ {0xFED9, 0xFEDA, 0xFEDB, 0xFEDC}, {0, 0, 0, 0} },	// kaf		(34)
+	{ {0xFEDD, 0xFEDE, 0xFEDF, 0xFEE0}, {0, 0, 0, 0} },	// lam		(35)
+	{ {0xFEE1, 0xFEE2, 0xFEE3, 0xFEE4}, {0, 0, 0, 0} },	// mim		(36)
+	{ {0xFEE5, 0xFEE6, 0xFEE7, 0xFEE8}, {0, 0, 0, 0} },	// noon		(37)
+	{ {0xFEE9, 0xFEEA, 0xFEEB, 0xFEEC}, {0, 0, 0, 0} },	// ha2		(38)
+	{ {0xFEED, 0xFEEE,      0,      0}, {0, 0, 0, 0} },	// waw		(39)
+	{ {0xFEFF, 0xFEF0,      0,      0}, {0, 0, 0, 0} },	// 2alif maksoura	(40)
+	{ {0xFEF1, 0xFEF2, 0xFEF3, 0xFEF4}, {0, 0, 0, 0} },	// ya2		(41)
 };
 
-bool is_arabic_letter(uint32_t cp)
-{
-	return ( cp >= ARABIC_LETTER_START && cp <=  ARABIC_LETTER_END );
-}
 
-bool is_linking_type(uint32_t cp)
-{
-	if( is_arabic_letter(cp) )
-		if( arabic_forms_b[cp - ARABIC_LETTER_START][INITIAL] || arabic_forms_b[cp - ARABIC_LETTER_START][MEDIAL] )
-			return true;
-	return false;
+
+static inline bool is_arabic_letter(uint32_t cp)		{ return ( cp >= ARABIC_LETTER_START && cp <=  ARABIC_LETTER_END ); }
+static inline bool is_lam_alef(uint32_t cp, uint32_t next)	{ return cp == 0x644 &&
+									 is_arabic_letter(next) &&
+									 arabic_forms_b[next - ARABIC_LETTER_START][1][INITIAL] != 0; }
+static inline bool is_alef_prev_lam(uint32_t prev, uint32_t cp)	{ return prev == 0x644 &&
+									 is_arabic_letter(cp) &&
+									 arabic_forms_b[cp - ARABIC_LETTER_START][1][INITIAL] != 0; }
+static inline bool is_linking_type(uint32_t cp) {
+	if( is_arabic_letter(cp) && ( arabic_forms_b[cp - ARABIC_LETTER_START][0][INITIAL] || arabic_forms_b[cp - ARABIC_LETTER_START][0][MEDIAL] ) ) {
+		return true;
+	} else {
+		return false;
+	}
 }
 
 
-uint32_t get_presentation_form_b(uint32_t prev, uint32_t next, uint32_t cp)
-{
-	if( !is_arabic_letter(cp) )
+uint32_t get_presentation_form_b(uint32_t prev, uint32_t next, uint32_t cp) {
+	if( !is_arabic_letter(cp) ) {
 		return cp;	/* not an Arabic letter */
+	}
+
+	if( is_lam_alef(cp, next) ) {
+		uint32_t index	= (is_linking_type(cp) << 1) | is_linking_type(prev);
+		return arabic_forms_b[next -  ARABIC_LETTER_START][1][index];
 
-	uint32_t index	= ((is_arabic_letter(next) & is_linking_type(cp)) << 1) | is_linking_type(prev);
+	} else {
+		if( is_alef_prev_lam(prev, cp) ) {
+			return -1;	// skip previously processed lam alef
+		} else {
+			uint32_t index	= ((is_arabic_letter(next) & is_linking_type(cp)) << 1) | is_linking_type(prev);
 
-	return arabic_forms_b[cp -  ARABIC_LETTER_START][index];
+			return arabic_forms_b[cp -  ARABIC_LETTER_START][0][index];
+		}
+	}
 }
diff --git a/mainwindow.cpp b/mainwindow.cpp
index ea3a91f..60d9d51 100644
--- a/mainwindow.cpp
+++ b/mainwindow.cpp
@@ -97,17 +97,30 @@ MainWindow::MainWindow(QWidget *parent) :
 	FT_Render_Mode	render_flags	= FT_RENDER_MODE_NORMAL;
 
 
-	data__	= new uchar[1024 * 256 * 4];
-	memset(data__, 0, 1024 * 256 * 4);
+	data__	= new uchar[1024 * 1024 * 4];
+	memset(data__, 0, 1024 * 1024 * 4);
 	int	col	= 1024 - 1;
 	int	line	= 100;
-	QImage	img(data__, 1024, 256, QImage::Format_RGB32);
+	QImage	img(data__, 1024, 1024, QImage::Format_RGB32);
 	// render the arabic glyphs
 	for( size_t idx = 0; idx < arabic_cp.size(); ++idx )
 	{
 		uint ch	= get_arabic_form(arabic_cp, idx);
-		if( ch == 0xA || ch == 0xC )
+		if( ch == 0xA ) {
+			line	+= 30;
+			col	= 1024 - 1;
 			continue;
+		}
+
+		if ( ch == 0xC ) {
+			continue;
+		}
+
+		if ( ch == -1 ) {
+			continue;
+		}
+
+		assert(ch != 0);
 
 		int glyph_index	= FT_Get_Char_Index(face, ch);
 		assert( glyph_index && "invalid character" );