1 | // Copyright (C) 2016 Klaralvdalens Datakonsult AB (KDAB). |
2 | // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only |
3 | |
4 | #include <QtGui/qrawfont.h> |
5 | #include <QtGui/qglyphrun.h> |
6 | #include <QtGui/private/qrawfont_p.h> |
7 | |
8 | #include "qdistancefieldglyphcache_p.h" |
9 | #include "qtextureatlas_p.h" |
10 | |
11 | #include <QtGui/qpainterpath.h> |
12 | #include <QtGui/qfont.h> |
13 | #include <QtGui/qpainterpath.h> |
14 | #include <QtGui/private/qdistancefield_p.h> |
15 | #include <Qt3DCore/private/qnode_p.h> |
16 | #include <Qt3DExtras/private/qtextureatlas_p.h> |
17 | |
18 | QT_BEGIN_NAMESPACE |
19 | |
20 | #define DEFAULT_IMAGE_PADDING 1 |
21 | |
22 | using namespace Qt3DCore; |
23 | |
24 | namespace Qt3DExtras { |
25 | |
26 | // ref-count glyphs and keep track of where they are stored |
27 | class { |
28 | public: |
29 | () = default; |
30 | StoredGlyph(const QRawFont &font, quint32 glyph, bool doubleResolution); |
31 | |
32 | int () const { return int(m_ref); } |
33 | void () { ++m_ref; } |
34 | int () { m_ref = std::max(a: m_ref - 1, b: quint32(0)); return int(m_ref); } |
35 | |
36 | bool addToTextureAtlas(QTextureAtlas *atlas); |
37 | void removeFromTextureAtlas(); |
38 | |
39 | QTextureAtlas *() const { return m_atlas; } |
40 | QRectF () const { return m_glyphPathBoundingRect; } |
41 | QRectF texCoords() const; |
42 | |
43 | private: |
44 | quint32 = 0; |
45 | QTextureAtlas * = nullptr; |
46 | QTextureAtlas::TextureId = QTextureAtlas::InvalidTexture; |
47 | QRectF ; |
48 | QImage ; // only used until added to texture atlas |
49 | }; |
50 | |
51 | // A DistanceFieldFont stores all glyphs for a given QRawFont. |
52 | // it will use multiple QTextureAtlasess to store the distance |
53 | // fields and uses ref-counting for each glyph to ensure that |
54 | // unused glyphs are removed from the texture atlasses. |
55 | class |
56 | { |
57 | public: |
58 | DistanceFieldFont(const QRawFont &font, bool doubleRes, Qt3DCore::QNode *parent); |
59 | ~DistanceFieldFont(); |
60 | |
61 | StoredGlyph findGlyph(quint32 glyph) const; |
62 | StoredGlyph refGlyph(quint32 glyph); |
63 | void derefGlyph(quint32 glyph); |
64 | |
65 | bool () const { return m_doubleGlyphResolution; } |
66 | |
67 | private: |
68 | QRawFont ; |
69 | bool ; |
70 | Qt3DCore::QNode *; // parent node for the QTextureAtlasses |
71 | |
72 | QHash<quint32, StoredGlyph> ; |
73 | |
74 | QList<QTextureAtlas*> ; |
75 | }; |
76 | |
77 | StoredGlyph::(const QRawFont &font, quint32 glyph, bool doubleResolution) |
78 | : m_ref(1) |
79 | , m_atlas(nullptr) |
80 | , m_atlasEntry(QTextureAtlas::InvalidTexture) |
81 | { |
82 | // create new single-channel distance field image for given glyph |
83 | const QPainterPath path = font.pathForGlyph(glyphIndex: glyph); |
84 | const QDistanceField dfield(font, glyph, doubleResolution); |
85 | m_distanceFieldImage = dfield.toImage(format: QImage::Format_Alpha8); |
86 | |
87 | // scale bounding rect down (as in QSGDistanceFieldGlyphCache::glyphData()) |
88 | const QRectF pathBound = path.boundingRect(); |
89 | float f = 1.0f / QT_DISTANCEFIELD_SCALE(narrowOutlineFont: doubleResolution); |
90 | m_glyphPathBoundingRect = QRectF(pathBound.left() * f, -pathBound.top() * f, pathBound.width() * f, pathBound.height() * f); |
91 | } |
92 | |
93 | bool StoredGlyph::(QTextureAtlas *atlas) |
94 | { |
95 | if (m_atlas || m_distanceFieldImage.isNull()) |
96 | return false; |
97 | |
98 | const auto texId = atlas->addImage(image: m_distanceFieldImage, DEFAULT_IMAGE_PADDING); |
99 | if (texId != QTextureAtlas::InvalidTexture) { |
100 | m_atlas = atlas; |
101 | m_atlasEntry = texId; |
102 | m_distanceFieldImage = QImage(); // free glyph image data |
103 | return true; |
104 | } |
105 | |
106 | return false; |
107 | } |
108 | |
109 | void StoredGlyph::() |
110 | { |
111 | if (m_atlas) { |
112 | m_atlas->removeImage(id: m_atlasEntry); |
113 | m_atlas = nullptr; |
114 | m_atlasEntry = QTextureAtlas::InvalidTexture; |
115 | } |
116 | } |
117 | |
118 | QRectF StoredGlyph::() const |
119 | { |
120 | return m_atlas ? m_atlas->imageTexCoords(id: m_atlasEntry) : QRectF(); |
121 | } |
122 | |
123 | DistanceFieldFont::(const QRawFont &font, bool doubleRes, Qt3DCore::QNode *parent) |
124 | : m_font(font) |
125 | , m_doubleGlyphResolution(doubleRes) |
126 | , m_parentNode(parent) |
127 | { |
128 | Q_ASSERT(m_parentNode); |
129 | } |
130 | |
131 | DistanceFieldFont::() |
132 | { |
133 | qDeleteAll(c: m_atlasses); |
134 | } |
135 | |
136 | StoredGlyph DistanceFieldFont::(quint32 glyph) const |
137 | { |
138 | const auto it = m_glyphs.find(key: glyph); |
139 | return (it != m_glyphs.cend()) ? it.value() : StoredGlyph(); |
140 | } |
141 | |
142 | StoredGlyph DistanceFieldFont::(quint32 glyph) |
143 | { |
144 | // if glyph already exists, just increase ref-count |
145 | auto it = m_glyphs.find(key: glyph); |
146 | if (it != m_glyphs.end()) { |
147 | it.value().ref(); |
148 | return it.value(); |
149 | } |
150 | |
151 | // need to create new glyph |
152 | StoredGlyph storedGlyph(m_font, glyph, m_doubleGlyphResolution); |
153 | |
154 | // see if one of the existing atlasses can hold the distance field image |
155 | for (int i = 0; i < m_atlasses.size(); i++) |
156 | if (storedGlyph.addToTextureAtlas(atlas: m_atlasses[i])) |
157 | break; |
158 | |
159 | // if no texture atlas is big enough (or no exists yet), allocate a new one |
160 | if (!storedGlyph.atlas()) { |
161 | // this should be enough to store 40-60 glyphs, which should be sufficient for most |
162 | // scenarios |
163 | const int size = m_doubleGlyphResolution ? 512 : 256; |
164 | |
165 | QTextureAtlas *atlas = new QTextureAtlas(); |
166 | atlas->setWidth(size); |
167 | atlas->setHeight(size); |
168 | atlas->setFormat(Qt3DRender::QAbstractTexture::R8_UNorm); |
169 | atlas->setPixelFormat(QOpenGLTexture::Red); |
170 | atlas->setMinificationFilter(Qt3DRender::QAbstractTexture::Linear); |
171 | atlas->setMagnificationFilter(Qt3DRender::QAbstractTexture::Linear); |
172 | atlas->setParent(m_parentNode); |
173 | m_atlasses << atlas; |
174 | |
175 | if (!storedGlyph.addToTextureAtlas(atlas)) |
176 | qWarning() << Q_FUNC_INFO << "Couldn't add glyph to newly allocated atlas. Glyph could be huge?" ; |
177 | } |
178 | |
179 | m_glyphs.insert(key: glyph, value: storedGlyph); |
180 | return storedGlyph; |
181 | } |
182 | |
183 | void DistanceFieldFont::(quint32 glyph) |
184 | { |
185 | auto it = m_glyphs.find(key: glyph); |
186 | if (it == m_glyphs.end()) |
187 | return; |
188 | |
189 | // TODO |
190 | // possible optimization: keep unreferenced glyphs as the texture atlas |
191 | // still has space. only if a new glyph needs to be allocated, and there |
192 | // is no more space within the atlas, then we can actually remove the glyphs |
193 | // from the atlasses. |
194 | |
195 | // remove glyph if no refs anymore |
196 | if (it.value().deref() <= 0) { |
197 | QTextureAtlas *atlas = it.value().atlas(); |
198 | it.value().removeFromTextureAtlas(); |
199 | |
200 | // remove atlas, if it contains no glyphs anymore |
201 | if (atlas && atlas->imageCount() == 0) { |
202 | Q_ASSERT(m_atlasses.contains(atlas)); |
203 | |
204 | m_atlasses.removeAll(t: atlas); |
205 | |
206 | // This function might have been called as a result of destroying |
207 | // the scene root which traverses the entire scene tree. Calling |
208 | // delete on the atlas here could lead to dangling pointers in the |
209 | // least of children being traversed for destruction. |
210 | atlas->deleteLater(); |
211 | } |
212 | |
213 | m_glyphs.erase(it); |
214 | } |
215 | } |
216 | |
217 | // copied from QSGDistanceFieldGlyphCacheManager::fontKey |
218 | // we use this function to compare QRawFonts, as QRawFont doesn't |
219 | // implement a stable comparison function |
220 | QString QDistanceFieldGlyphCache::(const QRawFont &font) |
221 | { |
222 | QFontEngine *fe = QRawFontPrivate::get(font)->fontEngine; |
223 | if (!fe->faceId().filename.isEmpty()) { |
224 | QByteArray keyName = fe->faceId().filename; |
225 | if (font.style() != QFont::StyleNormal) |
226 | keyName += QByteArray(" I" ); |
227 | if (font.weight() != QFont::Normal) |
228 | keyName += ' ' + QByteArray::number(font.weight()); |
229 | keyName += QByteArray(" DF" ); |
230 | return QString::fromUtf8(ba: keyName); |
231 | } else { |
232 | return QString::fromLatin1(ba: "%1_%2_%3_%4" ) |
233 | .arg(a: font.familyName()) |
234 | .arg(a: font.styleName()) |
235 | .arg(a: font.weight()) |
236 | .arg(a: font.style()); |
237 | } |
238 | } |
239 | |
240 | DistanceFieldFont* QDistanceFieldGlyphCache::(const QRawFont &font) |
241 | { |
242 | // return, if font already exists (make sure to only create one DistanceFieldFont for |
243 | // each unique QRawFont, by building a hash on the QRawFont that ignores the font size) |
244 | const QString key = fontKey(font); |
245 | const auto it = m_fonts.constFind(key); |
246 | if (it != m_fonts.cend()) |
247 | return it.value(); |
248 | |
249 | // logic taken from QSGDistanceFieldGlyphCache::QSGDistanceFieldGlyphCache |
250 | QRawFontPrivate *fontD = QRawFontPrivate::get(font); |
251 | const int glyphCount = fontD->fontEngine->glyphCount(); |
252 | const bool useDoubleRes = qt_fontHasNarrowOutlines(f: font) && glyphCount < QT_DISTANCEFIELD_HIGHGLYPHCOUNT(); |
253 | |
254 | // only keep one FontCache with a fixed pixel size for each distinct font type |
255 | QRawFont actualFont = font; |
256 | actualFont.setPixelSize(QT_DISTANCEFIELD_BASEFONTSIZE(narrowOutlineFont: useDoubleRes) * QT_DISTANCEFIELD_SCALE(narrowOutlineFont: useDoubleRes)); |
257 | |
258 | // create new font cache |
259 | // we set the parent node to nullptr, since the parent node of QTextureAtlasses |
260 | // will be set when we pass them to QText2DMaterial later |
261 | Q_ASSERT(m_rootNode); |
262 | DistanceFieldFont *dff = new DistanceFieldFont(actualFont, useDoubleRes, m_rootNode); |
263 | m_fonts.insert(key, value: dff); |
264 | return dff; |
265 | } |
266 | |
267 | QDistanceFieldGlyphCache::() |
268 | : m_rootNode(nullptr) |
269 | { |
270 | } |
271 | |
272 | QDistanceFieldGlyphCache::() |
273 | { |
274 | } |
275 | |
276 | void QDistanceFieldGlyphCache::(QNode *rootNode) |
277 | { |
278 | m_rootNode = rootNode; |
279 | } |
280 | |
281 | QNode *QDistanceFieldGlyphCache::() const |
282 | { |
283 | return m_rootNode; |
284 | } |
285 | |
286 | bool QDistanceFieldGlyphCache::(const QRawFont &font) |
287 | { |
288 | return getOrCreateDistanceFieldFont(font)->doubleGlyphResolution(); |
289 | } |
290 | |
291 | namespace { |
292 | QDistanceFieldGlyphCache::Glyph refAndGetGlyph(DistanceFieldFont *dff, quint32 glyph) |
293 | { |
294 | QDistanceFieldGlyphCache::Glyph ret; |
295 | |
296 | if (dff) { |
297 | const auto entry = dff->refGlyph(glyph); |
298 | |
299 | Q_ASSERT(entry.atlas()); |
300 | ret.glyphPathBoundingRect = entry.glyphPathBoundingRect(); |
301 | ret.texCoords = entry.texCoords(); |
302 | ret.texture = entry.atlas(); |
303 | } |
304 | |
305 | return ret; |
306 | } |
307 | } // anonymous |
308 | |
309 | QList<QDistanceFieldGlyphCache::Glyph> QDistanceFieldGlyphCache::(const QGlyphRun &run) |
310 | { |
311 | DistanceFieldFont *dff = getOrCreateDistanceFieldFont(font: run.rawFont()); |
312 | QList<QDistanceFieldGlyphCache::Glyph> ret; |
313 | |
314 | const auto glyphs = run.glyphIndexes(); |
315 | for (quint32 glyph : glyphs) |
316 | ret << refAndGetGlyph(dff, glyph); |
317 | |
318 | return ret; |
319 | } |
320 | |
321 | QDistanceFieldGlyphCache::Glyph QDistanceFieldGlyphCache::(const QRawFont &font, quint32 glyph) |
322 | { |
323 | return refAndGetGlyph(dff: getOrCreateDistanceFieldFont(font), glyph); |
324 | } |
325 | |
326 | void QDistanceFieldGlyphCache::(const QGlyphRun &run) |
327 | { |
328 | DistanceFieldFont *dff = getOrCreateDistanceFieldFont(font: run.rawFont()); |
329 | |
330 | const auto glyphs = run.glyphIndexes(); |
331 | for (quint32 glyph : glyphs) |
332 | dff->derefGlyph(glyph); |
333 | } |
334 | |
335 | void QDistanceFieldGlyphCache::(const QRawFont &font, quint32 glyph) |
336 | { |
337 | getOrCreateDistanceFieldFont(font)->derefGlyph(glyph); |
338 | } |
339 | |
340 | } // namespace Qt3DExtras |
341 | |
342 | QT_END_NAMESPACE |
343 | |