GRAPHICS: Add a TTF font class using FreeType2.

1 files changed, 443 insertions, 0 deletions

diff --git a/graphics/fonts/ttf.cpp b/graphics/fonts/ttf.cpp
new file mode 100644
index 0000000000..8a6b87c000
--- /dev/null
+++ b/graphics/fonts/ttf.cpp
@@ -0,0 +1,443 @@
+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
+// Since FreeType2 includes files, which contain forbidden symbols, we need to
+// allow all symbols here.
+#define FORBIDDEN_SYMBOL_ALLOW_ALL
+
+#include "common/scummsys.h"
+#ifdef USE_FREETYPE2
+
+#include "graphics/fonts/ttf.h"
+#include "graphics/font.h"
+#include "graphics/surface.h"
+
+#include "common/singleton.h"
+#include "common/stream.h"
+#include "common/hashmap.h"
+
+#include <ft2build.h>
+#include FT_FREETYPE_H
+#include FT_GLYPH_H
+
+namespace Graphics {
+
+namespace {
+
+inline int ftFloor26_6(FT_Pos x) {
+	return x / 64;
+}
+
+inline int ftCeil26_6(FT_Pos x) {
+	return (x + 63) / 64;
+}
+
+} // End of anonymous namespace
+
+class TTFLibrary : public Common::Singleton<TTFLibrary> {
+public:
+	TTFLibrary();
+	~TTFLibrary();
+
+	/**
+	 * Check whether FreeType2 is initialized properly.
+	 */
+	bool isInitialized() const { return _initialized; }
+
+	bool loadFont(const uint8 *file, const uint32 size, FT_Face &face);
+	void closeFont(FT_Face &face);
+private:
+	FT_Library _library;
+	bool _initialized;
+};
+
+#define g_ttf ::Graphics::TTFLibrary::instance()
+
+TTFLibrary::TTFLibrary() : _library(), _initialized(false) {
+	if (!FT_Init_FreeType(&_library))
+		_initialized = true;
+}
+
+TTFLibrary::~TTFLibrary() {
+	if (_initialized) {
+		FT_Done_FreeType(_library);
+		_initialized = false;
+	}
+}
+
+bool TTFLibrary::loadFont(const uint8 *file, const uint32 size, FT_Face &face) {
+	assert(_initialized);
+
+	return (FT_New_Memory_Face(_library, file, size, 0, &face) == 0);
+}
+
+void TTFLibrary::closeFont(FT_Face &face) {
+	assert(_initialized);
+
+	FT_Done_Face(face);
+}
+
+class TTFFont : public Font {
+public:
+	TTFFont();
+	virtual ~TTFFont();
+
+	bool load(Common::SeekableReadStream &stream, int size, bool monochrome);
+
+	virtual int getFontHeight() const;
+
+	virtual int getMaxCharWidth() const;
+
+	virtual int getCharWidth(byte chr) const;
+
+	virtual void drawChar(Surface *dst, byte chr, int x, int y, uint32 color) const;
+private:
+	bool _initialized;
+	FT_Face _face;
+
+	uint8 *_ttfFile;
+	uint32 _size;
+
+	int _width, _height;
+	int _ascent, _descent;
+
+	struct Glyph {
+		Surface image;
+		int xOffset, yOffset;
+		int advance;
+	};
+
+	bool cacheGlyph(Glyph &glyph, byte chr);
+	typedef Common::HashMap<byte, Glyph> GlyphCache;
+	GlyphCache _glyphs;
+
+	bool _monochrome;
+};
+
+TTFFont::TTFFont()
+    : _initialized(false), _face(), _ttfFile(0), _size(0), _width(0), _height(0), _ascent(0),
+      _descent(0), _glyphs(), _monochrome(false) {
+}
+
+TTFFont::~TTFFont() {
+	if (_initialized) {
+		g_ttf.closeFont(_face);
+
+		delete[] _ttfFile;
+		_ttfFile = 0;
+
+		for (GlyphCache::iterator i = _glyphs.begin(), end = _glyphs.end(); i != end; ++i)
+			i->_value.image.free();
+
+		_initialized = false;
+	}
+}
+
+bool TTFFont::load(Common::SeekableReadStream &stream, int size, bool monochrome) {
+	if (!g_ttf.isInitialized())
+		return false;
+
+	_size = stream.size();
+	if (!_size)
+		return false;
+
+	_ttfFile = new uint8[_size];
+	assert(_ttfFile);
+
+	if (stream.read(_ttfFile, _size) != _size) {
+		delete[] _ttfFile;
+		_ttfFile = 0;
+
+		return false;
+	}
+
+	if (!g_ttf.loadFont(_ttfFile, _size, _face)) {
+		delete[] _ttfFile;
+		_ttfFile = 0;
+
+		return false;
+	}
+
+	// We only support scalable fonts.
+	if (!FT_IS_SCALABLE(_face)) {
+		delete[] _ttfFile;
+		_ttfFile = 0;
+
+		g_ttf.closeFont(_face);
+
+		return false;
+	}
+
+	if (FT_Set_Char_Size(_face, 0, size * 64, 0, 0)) {
+		delete[] _ttfFile;
+		_ttfFile = 0;
+
+		return false;
+	}
+
+	_monochrome = monochrome;
+
+	FT_Fixed yScale = _face->size->metrics.y_scale;
+	_ascent = ftCeil26_6(FT_MulFix(_face->ascender, yScale));
+	_descent = ftCeil26_6(FT_MulFix(_face->descender, yScale));
+
+	_width = ftCeil26_6(FT_MulFix(_face->max_advance_width, _face->size->metrics.x_scale));
+	_height = _ascent - _descent + 1;
+
+	// Load all ISO-8859-1 characters.
+	for (uint i = 0; i < 256; ++i)
+		cacheGlyph(_glyphs[i], i);
+
+	_initialized = (_glyphs.size() != 0);
+	return _initialized;
+}
+
+int TTFFont::getFontHeight() const {
+	return _height;
+}
+
+int TTFFont::getMaxCharWidth() const {
+	return _width;
+}
+
+int TTFFont::getCharWidth(byte chr) const {
+	GlyphCache::const_iterator glyphEntry = _glyphs.find(chr);
+	if (glyphEntry == _glyphs.end())
+		return 0;
+	else
+		return glyphEntry->_value.advance;
+}
+
+namespace {
+
+template<typename ColorType>
+void renderGlyph(uint8 *dstPos, const int dstPitch, const uint8 *srcPos, const int srcPitch, const int w, const int h, ColorType color, const PixelFormat &dstFormat) {
+	uint8 sR, sG, sB;
+	dstFormat.colorToRGB(color, sR, sG, sB);
+
+	for (int y = 0; y < h; ++y) {
+		ColorType *rDst = (ColorType *)dstPos;
+		const uint8 *src = srcPos;
+
+		for (int x = 0; x < w; ++x) {
+			if (*src == 255) {
+				*rDst = color;
+			} else if (*src) {
+				const uint8 a = *src;
+
+				uint8 dR, dG, dB;
+				dstFormat.colorToRGB(*rDst, dR, dG, dB);
+
+				dR = ((255 - a) * dR + a * sR) / 255;
+				dG = ((255 - a) * dG + a * sG) / 255;
+				dB = ((255 - a) * dB + a * sB) / 255;
+
+				*rDst = dstFormat.RGBToColor(dR, dG, dB);
+			}
+
+			++rDst;
+			++src;
+		}
+
+		dstPos += dstPitch;
+		srcPos += srcPitch;
+	}
+}
+
+} // End of anonymous namespace
+
+void TTFFont::drawChar(Surface *dst, byte chr, int x, int y, uint32 color) const {
+	GlyphCache::const_iterator glyphEntry = _glyphs.find(chr);
+	if (glyphEntry == _glyphs.end())
+		return;
+
+	const Glyph &glyph = glyphEntry->_value;
+
+	x += glyph.xOffset;
+	y += glyph.yOffset;
+
+	if (x > dst->w)
+		return;
+	if (y > dst->h)
+		return;
+
+	int w = glyph.image.w;
+	int h = glyph.image.h;
+
+	const uint8 *srcPos = (const uint8 *)glyph.image.getBasePtr(0, 0);
+	uint8 *dstPos = (uint8 *)dst->getBasePtr(x, y);
+
+	// Make sure we are not drawing outside the screen bounds
+	if (x < 0) {
+		srcPos -= x;
+		w += x;
+		x = 0;
+	}
+
+	if (x + w > dst->w)
+		w = dst->w - x;
+
+	if (w <= 0)
+		return;
+
+	if (y < 0) {
+		srcPos += y * glyph.image.pitch;
+		h += y;
+		y = 0;
+	}
+
+	if (y + h > dst->h)
+		h = dst->h - y;
+
+	if (h <= 0)
+		return;
+
+	if (dst->format.bytesPerPixel == 1) {
+		for (int cy = 0; cy < h; ++cy) {
+			uint8 *rDst = dstPos;
+			const uint8 *src = srcPos;
+
+			for (int cx = 0; cx < w; ++cx) {
+				// We assume a 1Bpp mode is a color indexed mode, thus we can
+				// not take advantage of anti-aliasing here.
+				if (*src >= 0x80)
+					*rDst = color;
+
+				++rDst;
+				++src;
+			}
+
+			dstPos += dst->pitch;
+			srcPos += glyph.image.pitch;
+		}
+	} else if (dst->format.bytesPerPixel == 2) {
+		renderGlyph<uint16>(dstPos, dst->pitch, srcPos, glyph.image.pitch, w, h, color, dst->format);
+	} else if (dst->format.bytesPerPixel == 4) {
+		renderGlyph<uint32>(dstPos, dst->pitch, srcPos, glyph.image.pitch, w, h, color, dst->format);
+	}
+}
+
+bool TTFFont::cacheGlyph(Glyph &glyph, byte chr) {
+	FT_UInt slot = FT_Get_Char_Index(_face, chr);
+	if (!slot)
+		return false;
+
+	// We use the light target and render mode to improve the looks of the
+	// glyphs. It is most noticable in FreeSansBold.ttf, where otherwise the
+	// 't' glyph looks like it is cut off on the right side.
+	if (FT_Load_Glyph(_face, slot, (_monochrome ? FT_LOAD_MONOCHROME : FT_LOAD_TARGET_LIGHT)))
+		return false;
+
+	if (FT_Render_Glyph(_face->glyph, (_monochrome ? FT_RENDER_MODE_MONO : FT_RENDER_MODE_LIGHT)))
+		return false;
+
+	if (_face->glyph->format != FT_GLYPH_FORMAT_BITMAP)
+		return false;
+
+	FT_Glyph_Metrics &metrics = _face->glyph->metrics;
+
+	glyph.xOffset = ftFloor26_6(metrics.horiBearingX);
+	int xMax = glyph.xOffset + ftCeil26_6(metrics.width);
+	glyph.yOffset = _ascent - ftFloor26_6(metrics.horiBearingY);
+
+	glyph.advance = ftCeil26_6(metrics.horiAdvance);
+
+	// In case we got a negative xMin we adjust that, this might make some
+	// characters make a bit odd, but it's the only way we can assure no
+	// invalid memory writes with the current font API
+	if (glyph.xOffset < 0) {
+		xMax -= glyph.xOffset;
+		glyph.xOffset = 0;
+
+		if (xMax > glyph.advance)
+			glyph.advance = xMax;
+	}
+
+	const FT_Bitmap &bitmap = _face->glyph->bitmap;
+	glyph.image.create(bitmap.width, bitmap.rows, PixelFormat::createFormatCLUT8());
+
+	const uint8 *src = bitmap.buffer;
+	int srcPitch = bitmap.pitch;
+	if (srcPitch < 0) {
+		src += (bitmap.rows - 1) * srcPitch;
+		srcPitch = -srcPitch;
+	}
+
+	uint8 *dst = (uint8 *)glyph.image.getBasePtr(0, 0);
+	memset(dst, 0, glyph.image.h * glyph.image.pitch);
+
+	switch (bitmap.pixel_mode) {
+	case FT_PIXEL_MODE_MONO:
+		for (int y = 0; y < bitmap.rows; ++y) {
+			const uint8 *curSrc = src;
+			uint8 mask = 0;
+
+			for (int x = 0; x < bitmap.width; ++x) {
+				if ((x % 8) == 0)
+					mask = *curSrc++;
+
+				if (mask & 0x80)
+					*dst = 255;
+
+				mask <<= 1;
+				++dst;
+			}
+
+			src += srcPitch;
+		}
+		break;
+
+	case FT_PIXEL_MODE_GRAY:
+		for (int y = 0; y < bitmap.rows; ++y) {
+			memcpy(dst, src, bitmap.width);
+			dst += glyph.image.pitch;
+			src += srcPitch;
+		}
+		break;
+
+	default:
+		warning("TTFFont::cacheGlyph: Unsupported pixel mode %d", bitmap.pixel_mode);
+		return false;
+	}
+
+	return true;
+}
+
+Font *loadTTFFont(Common::SeekableReadStream &stream, int size, bool monochrome) {
+	TTFFont *font = new TTFFont();
+
+	if (!font->load(stream, size, monochrome)) {
+		delete font;
+		return 0;
+	}
+
+	return font;
+}
+
+} // End of namespace Graphics
+
+namespace Common {
+DECLARE_SINGLETON(Graphics::TTFLibrary);
+} // End of namespace Common
+
+#endif
+