[TextServer] Improvements for line breaking, "Fill" alignment, overrun, and interaction between these modes.

Fix "Fill" alignment processing wrong side of the text if overrun trim was applied.
Improve "Fill" alignment to avoid adding excessive subsequent spaces or elongations.
Add font detection to the overrun, to correctly add ellipsis (was using last glyph font, which doesn't necessary have dot character).
Improve line breaking to avoid adding excessive subsequent soft break points for languages without word separator.
Port missing overrun/justification code to the Fallback text server.
Fix inferred text direction detection by controls.
Add tests for "Fill" alignment and line breaking glyph flags.

1 files changed, 206 insertions, 0 deletions

diff --git a/tests/servers/test_text_server.h b/tests/servers/test_text_server.h
index b06f315bc8..0a64237285 100644
--- a/tests/servers/test_text_server.h
+++ b/tests/servers/test_text_server.h
@@ -154,6 +154,212 @@ TEST_SUITE("[[TextServer]") {
 			}
 		}
 
+		SUBCASE("[TextServer] Text layout: Line break and align points") {
+			for (int i = 0; i < TextServerManager::get_singleton()->get_interface_count(); i++) {
+				Ref<TextServer> ts = TextServerManager::get_singleton()->get_interface(i);
+				TEST_FAIL_COND(ts.is_null(), "Invalid TS interface.");
+
+				RID font1 = ts->create_font();
+				ts->font_set_data_ptr(font1, _font_NotoSans_Regular, _font_NotoSans_Regular_size);
+				RID font2 = ts->create_font();
+				ts->font_set_data_ptr(font2, _font_NotoSansThaiUI_Regular, _font_NotoSansThaiUI_Regular_size);
+				RID font3 = ts->create_font();
+				ts->font_set_data_ptr(font3, _font_NotoNaskhArabicUI_Regular, _font_NotoNaskhArabicUI_Regular_size);
+
+				Vector<RID> font;
+				font.push_back(font1);
+				font.push_back(font2);
+				font.push_back(font3);
+
+				{
+					String test = U"Test test long text long text\n";
+					RID ctx = ts->create_shaped_text();
+					TEST_FAIL_COND(ctx == RID(), "Creating text buffer failed.");
+					bool ok = ts->shaped_text_add_string(ctx, test, font, 16);
+					TEST_FAIL_COND(!ok, "Adding text to the buffer failed.");
+					ts->shaped_text_update_breaks(ctx);
+					ts->shaped_text_update_justification_ops(ctx);
+
+					const Glyph *glyphs = ts->shaped_text_get_glyphs(ctx);
+					int gl_size = ts->shaped_text_get_glyph_count(ctx);
+
+					TEST_FAIL_COND(gl_size != 30, "Invalid glyph count.");
+					for (int j = 0; j < gl_size; j++) {
+						bool hard = (glyphs[j].flags & TextServer::GRAPHEME_IS_BREAK_HARD) == TextServer::GRAPHEME_IS_BREAK_HARD;
+						bool soft = (glyphs[j].flags & TextServer::GRAPHEME_IS_BREAK_SOFT) == TextServer::GRAPHEME_IS_BREAK_SOFT;
+						bool space = (glyphs[j].flags & TextServer::GRAPHEME_IS_SPACE) == TextServer::GRAPHEME_IS_SPACE;
+						bool virt = (glyphs[j].flags & TextServer::GRAPHEME_IS_VIRTUAL) == TextServer::GRAPHEME_IS_VIRTUAL;
+						bool elo = (glyphs[j].flags & TextServer::GRAPHEME_IS_ELONGATION) == TextServer::GRAPHEME_IS_ELONGATION;
+						if (j == 4 || j == 9 || j == 14 || j == 19 || j == 24) {
+							TEST_FAIL_COND((!soft || !space || hard || virt || elo), "Invalid glyph flags.");
+						} else if (j == 29) {
+							TEST_FAIL_COND((soft || !space || !hard || virt || elo), "Invalid glyph flags.");
+						} else {
+							TEST_FAIL_COND((soft || space || hard || virt || elo), "Invalid glyph flags.");
+						}
+					}
+					ts->free(ctx);
+				}
+
+				{
+					String test = U"الحمـد";
+					RID ctx = ts->create_shaped_text();
+					TEST_FAIL_COND(ctx == RID(), "Creating text buffer failed.");
+					bool ok = ts->shaped_text_add_string(ctx, test, font, 16);
+					TEST_FAIL_COND(!ok, "Adding text to the buffer failed.");
+					ts->shaped_text_update_breaks(ctx);
+
+					const Glyph *glyphs = ts->shaped_text_get_glyphs(ctx);
+					int gl_size = ts->shaped_text_get_glyph_count(ctx);
+					TEST_FAIL_COND(gl_size != 6, "Invalid glyph count.");
+					for (int j = 0; j < gl_size; j++) {
+						bool hard = (glyphs[j].flags & TextServer::GRAPHEME_IS_BREAK_HARD) == TextServer::GRAPHEME_IS_BREAK_HARD;
+						bool soft = (glyphs[j].flags & TextServer::GRAPHEME_IS_BREAK_SOFT) == TextServer::GRAPHEME_IS_BREAK_SOFT;
+						bool space = (glyphs[j].flags & TextServer::GRAPHEME_IS_SPACE) == TextServer::GRAPHEME_IS_SPACE;
+						bool virt = (glyphs[j].flags & TextServer::GRAPHEME_IS_VIRTUAL) == TextServer::GRAPHEME_IS_VIRTUAL;
+						bool elo = (glyphs[j].flags & TextServer::GRAPHEME_IS_ELONGATION) == TextServer::GRAPHEME_IS_ELONGATION;
+						TEST_FAIL_COND((soft || space || hard || virt || elo), "Invalid glyph flags.");
+					}
+
+					if (ts->has_feature(TextServer::FEATURE_KASHIDA_JUSTIFICATION)) {
+						ts->shaped_text_update_justification_ops(ctx);
+
+						glyphs = ts->shaped_text_get_glyphs(ctx);
+						gl_size = ts->shaped_text_get_glyph_count(ctx);
+
+						TEST_FAIL_COND(gl_size != 6, "Invalid glyph count.");
+						for (int j = 0; j < gl_size; j++) {
+							bool hard = (glyphs[j].flags & TextServer::GRAPHEME_IS_BREAK_HARD) == TextServer::GRAPHEME_IS_BREAK_HARD;
+							bool soft = (glyphs[j].flags & TextServer::GRAPHEME_IS_BREAK_SOFT) == TextServer::GRAPHEME_IS_BREAK_SOFT;
+							bool space = (glyphs[j].flags & TextServer::GRAPHEME_IS_SPACE) == TextServer::GRAPHEME_IS_SPACE;
+							bool virt = (glyphs[j].flags & TextServer::GRAPHEME_IS_VIRTUAL) == TextServer::GRAPHEME_IS_VIRTUAL;
+							bool elo = (glyphs[j].flags & TextServer::GRAPHEME_IS_ELONGATION) == TextServer::GRAPHEME_IS_ELONGATION;
+							if (j == 1) {
+								TEST_FAIL_COND((soft || space || hard || virt || !elo), "Invalid glyph flags.");
+							} else {
+								TEST_FAIL_COND((soft || space || hard || virt || elo), "Invalid glyph flags.");
+							}
+						}
+					}
+					ts->free(ctx);
+				}
+
+				{
+					String test = U"الحمـد الرياضي العربي";
+					RID ctx = ts->create_shaped_text();
+					TEST_FAIL_COND(ctx == RID(), "Creating text buffer failed.");
+					bool ok = ts->shaped_text_add_string(ctx, test, font, 16);
+					TEST_FAIL_COND(!ok, "Adding text to the buffer failed.");
+					ts->shaped_text_update_breaks(ctx);
+
+					const Glyph *glyphs = ts->shaped_text_get_glyphs(ctx);
+					int gl_size = ts->shaped_text_get_glyph_count(ctx);
+
+					TEST_FAIL_COND(gl_size != 21, "Invalid glyph count.");
+					for (int j = 0; j < gl_size; j++) {
+						bool hard = (glyphs[j].flags & TextServer::GRAPHEME_IS_BREAK_HARD) == TextServer::GRAPHEME_IS_BREAK_HARD;
+						bool soft = (glyphs[j].flags & TextServer::GRAPHEME_IS_BREAK_SOFT) == TextServer::GRAPHEME_IS_BREAK_SOFT;
+						bool space = (glyphs[j].flags & TextServer::GRAPHEME_IS_SPACE) == TextServer::GRAPHEME_IS_SPACE;
+						bool virt = (glyphs[j].flags & TextServer::GRAPHEME_IS_VIRTUAL) == TextServer::GRAPHEME_IS_VIRTUAL;
+						bool elo = (glyphs[j].flags & TextServer::GRAPHEME_IS_ELONGATION) == TextServer::GRAPHEME_IS_ELONGATION;
+						if (j == 6 || j == 14) {
+							TEST_FAIL_COND((!soft || !space || hard || virt || elo), "Invalid glyph flags.");
+						} else {
+							TEST_FAIL_COND((soft || space || hard || virt || elo), "Invalid glyph flags.");
+						}
+					}
+
+					if (ts->has_feature(TextServer::FEATURE_KASHIDA_JUSTIFICATION)) {
+						ts->shaped_text_update_justification_ops(ctx);
+
+						glyphs = ts->shaped_text_get_glyphs(ctx);
+						gl_size = ts->shaped_text_get_glyph_count(ctx);
+
+						TEST_FAIL_COND(gl_size != 23, "Invalid glyph count.");
+						for (int j = 0; j < gl_size; j++) {
+							bool hard = (glyphs[j].flags & TextServer::GRAPHEME_IS_BREAK_HARD) == TextServer::GRAPHEME_IS_BREAK_HARD;
+							bool soft = (glyphs[j].flags & TextServer::GRAPHEME_IS_BREAK_SOFT) == TextServer::GRAPHEME_IS_BREAK_SOFT;
+							bool space = (glyphs[j].flags & TextServer::GRAPHEME_IS_SPACE) == TextServer::GRAPHEME_IS_SPACE;
+							bool virt = (glyphs[j].flags & TextServer::GRAPHEME_IS_VIRTUAL) == TextServer::GRAPHEME_IS_VIRTUAL;
+							bool elo = (glyphs[j].flags & TextServer::GRAPHEME_IS_ELONGATION) == TextServer::GRAPHEME_IS_ELONGATION;
+							if (j == 7 || j == 16) {
+								TEST_FAIL_COND((!soft || !space || hard || virt || elo), "Invalid glyph flags.");
+							} else if (j == 3 || j == 9) {
+								TEST_FAIL_COND((soft || space || hard || !virt || !elo), "Invalid glyph flags.");
+							} else if (j == 18) {
+								TEST_FAIL_COND((soft || space || hard || virt || !elo), "Invalid glyph flags.");
+							} else {
+								TEST_FAIL_COND((soft || space || hard || virt || elo), "Invalid glyph flags.");
+							}
+						}
+					}
+
+					ts->free(ctx);
+				}
+
+				{
+					String test = U"เป็น ภาษา ราชการ และ ภาษา";
+					RID ctx = ts->create_shaped_text();
+					TEST_FAIL_COND(ctx == RID(), "Creating text buffer failed.");
+					bool ok = ts->shaped_text_add_string(ctx, test, font, 16);
+					TEST_FAIL_COND(!ok, "Adding text to the buffer failed.");
+					ts->shaped_text_update_breaks(ctx);
+					ts->shaped_text_update_justification_ops(ctx);
+
+					const Glyph *glyphs = ts->shaped_text_get_glyphs(ctx);
+					int gl_size = ts->shaped_text_get_glyph_count(ctx);
+
+					TEST_FAIL_COND(gl_size != 25, "Invalid glyph count.");
+					for (int j = 0; j < gl_size; j++) {
+						bool hard = (glyphs[j].flags & TextServer::GRAPHEME_IS_BREAK_HARD) == TextServer::GRAPHEME_IS_BREAK_HARD;
+						bool soft = (glyphs[j].flags & TextServer::GRAPHEME_IS_BREAK_SOFT) == TextServer::GRAPHEME_IS_BREAK_SOFT;
+						bool space = (glyphs[j].flags & TextServer::GRAPHEME_IS_SPACE) == TextServer::GRAPHEME_IS_SPACE;
+						bool virt = (glyphs[j].flags & TextServer::GRAPHEME_IS_VIRTUAL) == TextServer::GRAPHEME_IS_VIRTUAL;
+						bool elo = (glyphs[j].flags & TextServer::GRAPHEME_IS_ELONGATION) == TextServer::GRAPHEME_IS_ELONGATION;
+						if (j == 4 || j == 9 || j == 16 || j == 20) {
+							TEST_FAIL_COND((!soft || !space || hard || virt || elo), "Invalid glyph flags.");
+						} else {
+							TEST_FAIL_COND((soft || space || hard || virt || elo), "Invalid glyph flags.");
+						}
+					}
+					ts->free(ctx);
+				}
+
+				if (ts->has_feature(TextServer::FEATURE_BREAK_ITERATORS)) {
+					String test = U"เป็นภาษาราชการและภาษา";
+					RID ctx = ts->create_shaped_text();
+					TEST_FAIL_COND(ctx == RID(), "Creating text buffer failed.");
+					bool ok = ts->shaped_text_add_string(ctx, test, font, 16);
+					TEST_FAIL_COND(!ok, "Adding text to the buffer failed.");
+					ts->shaped_text_update_breaks(ctx);
+					ts->shaped_text_update_justification_ops(ctx);
+
+					const Glyph *glyphs = ts->shaped_text_get_glyphs(ctx);
+					int gl_size = ts->shaped_text_get_glyph_count(ctx);
+
+					TEST_FAIL_COND(gl_size != 25, "Invalid glyph count.");
+					for (int j = 0; j < gl_size; j++) {
+						bool hard = (glyphs[j].flags & TextServer::GRAPHEME_IS_BREAK_HARD) == TextServer::GRAPHEME_IS_BREAK_HARD;
+						bool soft = (glyphs[j].flags & TextServer::GRAPHEME_IS_BREAK_SOFT) == TextServer::GRAPHEME_IS_BREAK_SOFT;
+						bool space = (glyphs[j].flags & TextServer::GRAPHEME_IS_SPACE) == TextServer::GRAPHEME_IS_SPACE;
+						bool virt = (glyphs[j].flags & TextServer::GRAPHEME_IS_VIRTUAL) == TextServer::GRAPHEME_IS_VIRTUAL;
+						bool elo = (glyphs[j].flags & TextServer::GRAPHEME_IS_ELONGATION) == TextServer::GRAPHEME_IS_ELONGATION;
+						if (j == 4 || j == 9 || j == 16 || j == 20) {
+							TEST_FAIL_COND((!soft || !space || hard || !virt || elo), "Invalid glyph flags.");
+						} else {
+							TEST_FAIL_COND((soft || space || hard || virt || elo), "Invalid glyph flags.");
+						}
+					}
+					ts->free(ctx);
+				}
+
+				for (int j = 0; j < font.size(); j++) {
+					ts->free(font[j]);
+				}
+				font.clear();
+			}
+		}
+
 		SUBCASE("[TextServer] Text layout: Line breaking") {
 			for (int i = 0; i < TextServerManager::get_singleton()->get_interface_count(); i++) {
 				Ref<TextServer> ts = TextServerManager::get_singleton()->get_interface(i);