UI: disable new text hinting from D3201 by default for now.

This changes the text hinting setting to be an enum with options
Auto / None / Slight / Full. The default is Auto which currently disables
hinting.

The hinting was tested with a new FreeType version, but this is not what
is used on the buildbots an official release environment, and the fonts
look quite bad because of that. Once FreeType has been upgraded we can
change the default.

Even then the results are not ideal, perhaps due to missing subpixel
positioning and linear color blending support in BLF.

release/scripts/startup/bl_ui/space_userpref.py

@@ -538,9 +538,10 @@ class USERPREF_PT_system(Panel):
         col.separator()
 
         col.label(text="Text Draw Options:")
-        col.prop(system, "use_text_antialiasing")
-        if system.use_text_antialiasing:
-            col.prop(system, "use_text_hinting")
+        col.prop(system, "use_text_antialiasing", text="Anti-aliasing")
+        sub = col.column()
+        sub.active = system.use_text_antialiasing
+        sub.prop(system, "text_hinting", text="Hinting")
 
         col.separator()
 

source/blender/blenfont/BLF_api.h

@@ -218,9 +218,11 @@ void BLF_state_print(int fontid);
 #define BLF_KERNING_DEFAULT  (1 << 3)
 #define BLF_MATRIX           (1 << 4)
 #define BLF_ASPECT           (1 << 5)
-#define BLF_HINTING          (1 << 6)
-#define BLF_WORD_WRAP        (1 << 7)
-#define BLF_MONOCHROME       (1 << 8)  /* no-AA */
+#define BLF_WORD_WRAP        (1 << 6)
+#define BLF_MONOCHROME       (1 << 7)  /* no-AA */
+#define BLF_HINTING_NONE     (1 << 8)
+#define BLF_HINTING_SLIGHT   (1 << 9)
+#define BLF_HINTING_FULL     (1 << 10)
 
 #define BLF_DRAW_STR_DUMMY_MAX 1024
 

source/blender/blenfont/intern/blf_glyph.c

@@ -221,7 +221,6 @@ GlyphBLF *blf_glyph_add(FontBLF *font, unsigned int index, unsigned int c)
 	GlyphBLF *g;
 	FT_Error err;
 	FT_Bitmap bitmap, tempbitmap;
-	int flags = FT_LOAD_TARGET_NORMAL | FT_LOAD_NO_HINTING | FT_LOAD_NO_BITMAP;
 	FT_BBox bbox;
 	unsigned int key;
 
@@ -242,13 +241,27 @@ GlyphBLF *blf_glyph_add(FontBLF *font, unsigned int index, unsigned int c)
 		return g;
 	}
 
-	if (font->flags & BLF_HINTING)
-		flags &= ~FT_LOAD_NO_HINTING;
-
 	if (font->flags & BLF_MONOCHROME) {
 		err = FT_Load_Glyph(font->face, (FT_UInt)index, FT_LOAD_TARGET_MONO);
 	}
 	else {
+		int flags = FT_LOAD_NO_BITMAP;
+
+		if (font->flags & BLF_HINTING_NONE) {
+			flags |= FT_LOAD_TARGET_NORMAL | FT_LOAD_NO_HINTING;
+		}
+		else if (font->flags & BLF_HINTING_SLIGHT) {
+			flags |= FT_LOAD_TARGET_LIGHT;
+		}
+		else if (font->flags & BLF_HINTING_FULL) {
+			flags |= FT_LOAD_TARGET_NORMAL;
+		}
+		else {
+			/* Default, hinting disabled until FreeType has been upgraded
+			 * to give good results on all platforms. */
+			flags |= FT_LOAD_TARGET_NORMAL | FT_LOAD_NO_HINTING;
+		}
+
 		err = FT_Load_Glyph(font->face, (FT_UInt)index, flags);
 	}
 

source/blender/editors/interface/interface_style.c

@@ -523,30 +523,35 @@ void uiStyleInit(void)
 
 	/* Set default flags based on UI preferences (not render fonts) */
 	{
-		int flag_enable = 0, flag_disable = 0;
-		if ((U.text_render & USER_TEXT_DISABLE_HINTING) == 0) {
-			flag_enable |= BLF_HINTING;
+		int flag_disable = BLF_MONOCHROME |
+		                   BLF_HINTING_NONE |
+		                   BLF_HINTING_SLIGHT |
+		                   BLF_HINTING_FULL;
+		int flag_enable = 0;
+
+		if (U.text_render & USER_TEXT_HINTING_NONE) {
+			flag_enable |= BLF_HINTING_NONE;
 		}
-		else {
-			flag_disable |= BLF_HINTING;
+		else if (U.text_render & USER_TEXT_HINTING_SLIGHT) {
+			flag_enable |= BLF_HINTING_SLIGHT;
+		}
+		else if (U.text_render & USER_TEXT_HINTING_FULL) {
+			flag_enable |= BLF_HINTING_FULL;
 		}
 
 		if (U.text_render & USER_TEXT_DISABLE_AA) {
 			flag_enable |= BLF_MONOCHROME;
 		}
-		else {
-			flag_disable |= BLF_MONOCHROME;
-		}
 
 		for (font = U.uifonts.first; font; font = font->next) {
 			if (font->blf_id != -1) {
-				BLF_enable(font->blf_id, flag_enable);
 				BLF_disable(font->blf_id, flag_disable);
+				BLF_enable(font->blf_id, flag_enable);
 			}
 		}
 		if (blf_mono_font != -1) {
-			BLF_enable(blf_mono_font, flag_enable);
 			BLF_disable(blf_mono_font, flag_disable);
+			BLF_enable(blf_mono_font, flag_enable);
 		}
 	}
 

source/blender/makesdna/DNA_userdef_types.h

@@ -67,7 +67,7 @@ typedef struct uiFont {
 	short blf_id;		/* from blfont lib */
 	short uifont_id;	/* own id (eUIFont_ID) */
 	short r_to_l;		/* fonts that read from left to right */
-	short hinting;
+	short pad;
 } uiFont;
 
 /* this state defines appearance of text */
@@ -805,7 +805,10 @@ typedef enum eWM_DrawMethod {
  * UserDef.text_render */
 typedef enum eText_Draw_Options {
 	USER_TEXT_DISABLE_AA	  = (1 << 0),
-	USER_TEXT_DISABLE_HINTING = (1 << 1),
+
+	USER_TEXT_HINTING_NONE    = (1 << 1),
+	USER_TEXT_HINTING_SLIGHT  = (1 << 2),
+	USER_TEXT_HINTING_FULL    = (1 << 3),
 } eText_Draw_Options;
 
 /* tw_flag (transform widget) */

source/blender/makesrna/intern/rna_userdef.c

@@ -3973,6 +3973,14 @@ static void rna_def_userdef_system(BlenderRNA *brna)
 	    {0, NULL, 0, NULL, NULL}
 	};
 
+	static const EnumPropertyItem text_hinting_items[] = {
+	    {0, "AUTO", 0, "Auto", ""},
+	    {USER_TEXT_HINTING_NONE, "NONE", 0, "None", ""},
+	    {USER_TEXT_HINTING_SLIGHT, "SLIGHT", 0, "Slight", ""},
+	    {USER_TEXT_HINTING_FULL, "FULL", 0, "Full", ""},
+	    {0, NULL, 0, NULL, NULL}
+	};
+
 	srna = RNA_def_struct(brna, "UserPreferencesSystem", NULL);
 	RNA_def_struct_sdna(srna, "UserDef");
 	RNA_def_struct_nested(brna, srna, "UserPreferences");
@@ -4207,9 +4215,10 @@ static void rna_def_userdef_system(BlenderRNA *brna)
 	RNA_def_property_ui_text(prop, "Text Anti-aliasing", "Draw user interface text anti-aliased");
 	RNA_def_property_update(prop, 0, "rna_userdef_text_update");
 
-	prop = RNA_def_property(srna, "use_text_hinting", PROP_BOOLEAN, PROP_NONE);
-	RNA_def_property_boolean_negative_sdna(prop, NULL, "text_render", USER_TEXT_DISABLE_HINTING);
-	RNA_def_property_ui_text(prop, "Text Hinting", "Draw user interface text with hinting");
+	prop = RNA_def_property(srna, "text_hinting", PROP_ENUM, PROP_NONE);
+	RNA_def_property_enum_bitflag_sdna(prop, NULL, "text_render");
+	RNA_def_property_enum_items(prop, text_hinting_items);
+	RNA_def_property_ui_text(prop, "Text Hinting", "Method for making user interface text render sharp");
 	RNA_def_property_update(prop, 0, "rna_userdef_text_update");
 
 	prop = RNA_def_property(srna, "select_method", PROP_ENUM, PROP_NONE);