Font: Work on support for spacing modes.

* Change default spacing to B_BITMAP_SPACING. The BeBook does not document
   what the default spacing is, and I have no BeOS install handy to check.
   However, I believe that B_BITMAP_SPACING is what should be the default,
   since it gives the best visible result for the common use-case.
   In terms of implementation, there is no change, since spacing was ignored
   until now and the behavior was that of B_BITMAP_SPACING. This change could
   however break BeOS apps which assume B_CHAR_SPACING is the default and don't
   set it on new when they need it. Sample code in the BeBook however shows
   setting B_CHAR_SPACING on a newly created BFont.
 * Implement B_STRING_SPACING to do something sensible. The BeBook documentation
   is completely vague in what it is actually supposed to do. Given the
   possibilities of FreeType, I am implementing it to enable the use of
   kerning. Kerning optimizes the spacing between two glyphs, for example, it
   would decrease the spacing between "T" and "e" in the string "Test" for
   our default font. Untested.

src/kits/interface/Font.cpp

@@ -503,7 +503,7 @@ BFont::BFont()
 	fShear(90.0),
 	fRotation(0.0),
 	fFalseBoldWidth(0.0),
-	fSpacing(B_CHAR_SPACING),
+	fSpacing(B_BITMAP_SPACING),
 	fEncoding(B_UNICODE_UTF8),
 	fFace(0),
 	fFlags(0),

src/servers/app/ServerFont.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright 2001-2009, Haiku.
+ * Copyright 2001-2014, Haiku.
  * Distributed under the terms of the MIT License.
  *
  * Authors:
@@ -118,20 +118,20 @@ is_white_space(uint32 charCode)
 	\param flags Style flags as defined in <Font.h>
 	\param spacing String spacing flag as defined in <Font.h>
 */
-ServerFont::ServerFont(FontStyle& style, float size,
+ServerFont::ServerFont(FontStyle& style, float size, float rotation,
-					   float rotation, float shear, float falseBoldWidth,
+		float shear, float falseBoldWidth, uint16 flags, uint8 spacing)
-					   uint16 flags, uint8 spacing)
+	:
-	: fStyle(&style),
+	fStyle(&style),
-	  fSize(size),
+	fSize(size),
-	  fRotation(rotation),
+	fRotation(rotation),
-	  fShear(shear),
+	fShear(shear),
-	  fFalseBoldWidth(falseBoldWidth),
+	fFalseBoldWidth(falseBoldWidth),
-	  fBounds(0, 0, 0, 0),
+	fBounds(0, 0, 0, 0),
-	  fFlags(flags),
+	fFlags(flags),
-	  fSpacing(spacing),
+	fSpacing(spacing),
-	  fDirection(style.Direction()),
+	fDirection(style.Direction()),
-	  fFace(style.Face()),
+	fFace(style.Face()),
-	  fEncoding(B_UNICODE_UTF8)
+	fEncoding(B_UNICODE_UTF8)
 {
 	fStyle->Acquire();
 }
@@ -465,11 +465,9 @@ ServerFont::GetHasGlyphs(const char* string, int32 numBytes,
 	if (!string || numBytes <= 0 || !hasArray)
 		return B_BAD_DATA;
 
-	bool kerning = true; // TODO make this a property?
-
 	HasGlyphsConsumer consumer(hasArray);
 	if (GlyphLayoutEngine::LayoutGlyphs(consumer, *this, string, numBytes,
-		NULL, kerning, fSpacing))
+		NULL, fSpacing))
 		return B_OK;
 
 	return B_ERROR;
@@ -513,12 +511,11 @@ ServerFont::GetEdges(const char* string, int32 numBytes,
 	if (!string || numBytes <= 0 || !edges)
 		return B_BAD_DATA;
 
-	bool kerning = true; // TODO make this a property?
-
 	EdgesConsumer consumer(edges, fSize);
 	if (GlyphLayoutEngine::LayoutGlyphs(consumer, *this, string, numBytes,
-		NULL, kerning, fSpacing))
+		NULL, fSpacing)) {
 		return B_OK;
+	}
 
 	return B_ERROR;
 
@@ -603,13 +600,12 @@ ServerFont::GetEscapements(const char* string, int32 numBytes, int32 numChars,
 	if (!string || numBytes <= 0 || !escapementArray)
 		return B_BAD_DATA;
 
-	bool kerning = true; // TODO make this a property?
-
 	BPointEscapementConsumer consumer(escapementArray, offsetArray, numChars,
 		fSize);
 	if (GlyphLayoutEngine::LayoutGlyphs(consumer, *this, string, numBytes,
-		&delta, kerning, fSpacing))
+		&delta, fSpacing)) {
 		return B_OK;
+	}
 
 	return B_ERROR;
 }
@@ -659,12 +655,11 @@ ServerFont::GetEscapements(const char* string, int32 numBytes, int32 numChars,
 	if (!string || numBytes <= 0 || !widthArray)
 		return B_BAD_DATA;
 
-	bool kerning = true; // TODO make this a property?
-
 	WidthEscapementConsumer consumer(widthArray, numChars, fSize);
 	if (GlyphLayoutEngine::LayoutGlyphs(consumer, *this, string, numBytes,
-		&delta, kerning, fSpacing))
+		&delta, fSpacing)) {
 		return B_OK;
+	}
 	return B_ERROR;
 }
 
@@ -767,14 +762,13 @@ ServerFont::GetBoundingBoxes(const char* string, int32 numBytes,
 	if (!string || numBytes <= 0 || !rectArray)
 		return B_BAD_DATA;
 
-	bool kerning = true; // TODO make this a property?
-
 	Transformable transform(EmbeddedTransformation());
 
 	BoundingBoxConsumer consumer(transform, rectArray, asString);
 	if (GlyphLayoutEngine::LayoutGlyphs(consumer, *this, string, numBytes,
-		stringEscapement ? &delta : NULL, kerning, fSpacing))
+		stringEscapement ? &delta : NULL, fSpacing)) {
 		return B_OK;
+	}
 	return B_ERROR;
 }
 
@@ -788,8 +782,6 @@ ServerFont::GetBoundingBoxesForStrings(char *charArray[], int32 lengthArray[],
 	if (!charArray || !lengthArray|| numStrings <= 0 || !rectArray || !deltaArray)
 		return B_BAD_DATA;
 
-	bool kerning = true; // TODO make this a property?
-
 	Transformable transform(EmbeddedTransformation());
 
 	for (int32 i = 0; i < numStrings; i++) {
@@ -799,8 +791,9 @@ ServerFont::GetBoundingBoxesForStrings(char *charArray[], int32 lengthArray[],
 
 		BoundingBoxConsumer consumer(transform, NULL, true);
 		if (!GlyphLayoutEngine::LayoutGlyphs(consumer, *this, string, numBytes,
-			&delta, kerning, fSpacing))
+			&delta, fSpacing)) {
 			return B_ERROR;
+		}
 
 		rectArray[i] = consumer.stringBoundingBox;
 	}
@@ -832,12 +825,11 @@ ServerFont::StringWidth(const char *string, int32 numBytes,
 	if (!string || numBytes <= 0)
 		return 0.0;
 
-	bool kerning = true; // TODO make this a property?
-
 	StringWidthConsumer consumer;
 	if (!GlyphLayoutEngine::LayoutGlyphs(consumer, *this, string, numBytes,
-			deltaArray, kerning, fSpacing))
+			deltaArray, fSpacing)) {
 		return 0.0;
+	}
 
 	return consumer.width;
 }

src/servers/app/ServerFont.h

@@ -32,7 +32,7 @@ class ServerFont {
 										   float shear = 90.0,
 										   float falseBoldWidth = 0.0,
 										   uint16 flags = 0,
-										   uint8 spacing = B_CHAR_SPACING);
+										   uint8 spacing = B_BITMAP_SPACING);
 								ServerFont(const ServerFont& font);
 	virtual						~ServerFont();
 

src/servers/app/drawing/Painter/AGGTextRenderer.cpp

@@ -59,7 +59,6 @@ AGGTextRenderer::AGGTextRenderer(renderer_subpix_type& subpixRenderer,
 
 	fHinted(true),
 	fAntialias(true),
-	fKerning(true),
 	fEmbeddedTransformation(),
 	fViewTransformation(viewTransformation)
 {
@@ -365,7 +364,7 @@ AGGTextRenderer::RenderString(const char* string, uint32 length,
 		transform, transformOffset, nextCharPos, *this);
 
 	GlyphLayoutEngine::LayoutGlyphs(renderer, fFont, string, length, delta,
-		fKerning, B_BITMAP_SPACING, NULL, cacheReference);
+		fFont.Spacing(), NULL, cacheReference);
 
 	return transform.TransformBounds(renderer.Bounds());
 }
@@ -402,7 +401,7 @@ AGGTextRenderer::RenderString(const char* string, uint32 length,
 		transform, transformOffset, nextCharPos, *this);
 
 	GlyphLayoutEngine::LayoutGlyphs(renderer, fFont, string, length, NULL,
-		fKerning, B_BITMAP_SPACING, offsets, cacheReference);
+		fFont.Spacing(), offsets, cacheReference);
 
 	return transform.TransformBounds(renderer.Bounds());
 }

src/servers/app/drawing/Painter/AGGTextRenderer.h

@@ -47,10 +47,6 @@ public:
 			bool				Antialiasing() const
 									{ return fAntialias; }
 
-			void				SetKerning(bool kerning);
-			bool				Kerning() const
-									{ return fKerning; }
-
 			BRect				RenderString(const char* utf8String,
 									uint32 length, const BPoint& baseLine,
 									const BRect& clippingFrame, bool dryRun,
@@ -97,7 +93,6 @@ private:
 	bool						fHinted;
 									// is glyph hinting active?
 	bool						fAntialias;
-	bool						fKerning;
 	Transformable				fEmbeddedTransformation;
 									// rotated or sheared font?
 	agg::trans_affine&			fViewTransformation;

src/servers/app/font/GlyphLayoutEngine.h

@@ -1,5 +1,5 @@
 /*
- * Copyright 2007, Haiku. All rights reserved.
+ * Copyright 2007-2014, Haiku. All rights reserved.
  * Distributed under the terms of the MIT License.
  *
  * Authors:
@@ -92,7 +92,6 @@ public:
 									const char* utf8String,
 									int32 length,
 									const escapement_delta* delta = NULL,
-									bool kerning = true,
 									uint8 spacing = B_BITMAP_SPACING,
 									const BPoint* offsets = NULL,
 									FontCacheReference* cacheReference = NULL);
@@ -173,7 +172,7 @@ inline bool
 GlyphLayoutEngine::LayoutGlyphs(GlyphConsumer& consumer,
 	const ServerFont& font,
 	const char* utf8String, int32 length,
-	const escapement_delta* delta, bool kerning, uint8 spacing,
+	const escapement_delta* delta, uint8 spacing,
 	const BPoint* offsets, FontCacheReference* _cacheReference)
 {
 	// TODO: implement spacing modes
@@ -212,7 +211,7 @@ GlyphLayoutEngine::LayoutGlyphs(GlyphConsumer& consumer,
 	double advanceX = 0.0;
 	double advanceY = 0.0;
 
-//	uint32 lastCharCode = 0; // Needed for kerning, see below
+	uint32 lastCharCode = 0; // Needed for kerning in B_STRING_SPACING mode
 	uint32 charCode;
 	int32 index = 0;
 	bool writeLocked = false;
@@ -225,10 +224,8 @@ GlyphLayoutEngine::LayoutGlyphs(GlyphConsumer& consumer,
 			x = offsets[index].x;
 			y = offsets[index].y;
 		} else {
-// TODO: Currently disabled, because it works much too slow (doesn't seem
+			if (spacing == B_STRING_SPACING)
-// to be properly cached in FreeType.)
+				entry->GetKerning(lastCharCode, charCode, &advanceX, &advanceY);
-//			if (kerning)
-//				entry->GetKerning(lastCharCode, charCode, &advanceX, &advanceY);
 
 			x += advanceX;
 			y += advanceY;
@@ -273,7 +270,7 @@ GlyphLayoutEngine::LayoutGlyphs(GlyphConsumer& consumer,
 			}
 		}
 
-//		lastCharCode = charCode;
+		lastCharCode = charCode;
 		if (utf8String - start + 1 > length)
 			break;
 	}