SkTestScalerContext.cpp revision 2880df2609eba09b555ca37be04b6ad89290c765 
1/*
2 * Copyright 2014 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8#include "SkAdvancedTypefaceMetrics.h"
9#include "SkBitmap.h"
10#include "SkCanvas.h"
11#include "SkDescriptor.h"
12#include "SkFontDescriptor.h"
13#include "SkGlyph.h"
14#include "SkMask.h"
15// #include "SkOTUtils.h"
16#include "SkScalerContext.h"
17#include "SkTestScalerContext.h"
18#include "SkTypefaceCache.h"
19
20SkTestFont::SkTestFont(const SkTestFontData& fontData)
21    : INHERITED()
22    , fCharCodes(fontData.fCharCodes)
23    , fCharCodesCount(fontData.fCharCodesCount)
24    , fWidths(fontData.fWidths)
25    , fMetrics(fontData.fMetrics)
26    , fName(fontData.fName)
27    , fPaths(nullptr)
28{
29    init(fontData.fPoints, fontData.fVerbs);
30#ifdef SK_DEBUG
31    sk_bzero(fDebugBits, sizeof(fDebugBits));
32    sk_bzero(fDebugOverage, sizeof(fDebugOverage));
33#endif
34}
35
36SkTestFont::~SkTestFont() {
37    for (unsigned index = 0; index < fCharCodesCount; ++index) {
38        delete fPaths[index];
39    }
40    delete[] fPaths;
41}
42
43#ifdef SK_DEBUG
44
45#include "SkMutex.h"
46SK_DECLARE_STATIC_MUTEX(gUsedCharsMutex);
47
48#endif
49
50int SkTestFont::codeToIndex(SkUnichar charCode) const {
51#ifdef SK_DEBUG  // detect missing test font data
52    {
53        SkAutoMutexAcquire ac(gUsedCharsMutex);
54        if (charCode >= ' ' && charCode <= '~') {
55            int bitOffset = charCode - ' ';
56            fDebugBits[bitOffset >> 3] |= 1 << (bitOffset & 7);
57        } else {
58            int index = 0;
59            while (fDebugOverage[index] != 0 && fDebugOverage[index] != charCode
60                    && index < (int) sizeof(fDebugOverage)) {
61                ++index;
62            }
63            SkASSERT(index < (int) sizeof(fDebugOverage));
64            if (fDebugOverage[index] == 0) {
65                fDebugOverage[index] = charCode;
66            }
67        }
68    }
69#endif
70    for (unsigned index = 0; index < fCharCodesCount; ++index) {
71        if (fCharCodes[index] == (unsigned) charCode) {
72            return (int) index;
73        }
74    }
75    SkDEBUGF(("missing '%c' (%d) from %s %d\n", (char) charCode, charCode,
76            fDebugName, fDebugStyle));
77    return 0;
78}
79
80void SkTestFont::init(const SkScalar* pts, const unsigned char* verbs) {
81    fPaths = new SkPath* [fCharCodesCount];
82    for (unsigned index = 0; index < fCharCodesCount; ++index) {
83        SkPath* path = new SkPath;
84        SkPath::Verb verb;
85        while ((verb = (SkPath::Verb) *verbs++) != SkPath::kDone_Verb) {
86            switch (verb) {
87                case SkPath::kMove_Verb:
88                    path->moveTo(pts[0], pts[1]);
89                    pts += 2;
90                    break;
91                case SkPath::kLine_Verb:
92                    path->lineTo(pts[0], pts[1]);
93                    pts += 2;
94                    break;
95                case SkPath::kQuad_Verb:
96                    path->quadTo(pts[0], pts[1], pts[2], pts[3]);
97                    pts += 4;
98                    break;
99                case SkPath::kCubic_Verb:
100                    path->cubicTo(pts[0], pts[1], pts[2], pts[3], pts[4], pts[5]);
101                    pts += 6;
102                    break;
103                case SkPath::kClose_Verb:
104                    path->close();
105                    break;
106                default:
107                    SkDEBUGFAIL("bad verb");
108                    return;
109            }
110        }
111        // This should make SkPath::getBounds() queries threadsafe.
112        path->updateBoundsCache();
113        fPaths[index] = path;
114    }
115}
116
117SkTestTypeface::SkTestTypeface(SkTestFont* testFont, const SkFontStyle& style)
118    : SkTypeface(style, SkTypefaceCache::NewFontID(), false)
119    , fTestFont(testFont) {
120}
121
122void SkTestTypeface::getAdvance(SkGlyph* glyph) {
123    glyph->fAdvanceX = fTestFont->fWidths[glyph->getGlyphID()];
124    glyph->fAdvanceY = 0;
125}
126
127void SkTestTypeface::getFontMetrics(SkPaint::FontMetrics* metrics) {
128    *metrics = fTestFont->fMetrics;
129}
130
131void SkTestTypeface::getMetrics(SkGlyph* glyph) {
132    glyph->fAdvanceX = fTestFont->fWidths[glyph->getGlyphID()];
133    glyph->fAdvanceY = 0;
134}
135
136void SkTestTypeface::getPath(const SkGlyph& glyph, SkPath* path) {
137    *path = *fTestFont->fPaths[glyph.getGlyphID()];
138}
139
140void SkTestTypeface::onFilterRec(SkScalerContextRec* rec) const {
141    rec->setHinting(SkPaint::kNo_Hinting);
142}
143
144SkAdvancedTypefaceMetrics* SkTestTypeface::onGetAdvancedTypefaceMetrics(
145                                PerGlyphInfo ,
146                                const uint32_t* glyphIDs,
147                                uint32_t glyphIDsCount) const {
148// pdf only
149    SkAdvancedTypefaceMetrics* info = new SkAdvancedTypefaceMetrics;
150    info->fFontName.set(fTestFont->fName);
151    info->fLastGlyphID = SkToU16(onCountGlyphs() - 1);
152    return info;
153}
154
155void SkTestTypeface::onGetFontDescriptor(SkFontDescriptor* desc, bool* isLocal) const {
156    desc->setFamilyName(fTestFont->fName);
157    *isLocal = false;
158}
159
160int SkTestTypeface::onCharsToGlyphs(const void* chars, Encoding encoding,
161                            uint16_t glyphs[], int glyphCount) const {
162    SkASSERT(encoding == kUTF16_Encoding);
163    for (int index = 0; index < glyphCount; ++index) {
164        SkUnichar ch = ((SkUnichar*) chars)[index];
165        glyphs[index] = fTestFont->codeToIndex(ch);
166    }
167    return glyphCount;
168}
169
170void SkTestTypeface::onGetFamilyName(SkString* familyName) const {
171    *familyName = fTestFont->fName;
172}
173
174SkTypeface::LocalizedStrings* SkTestTypeface::onCreateFamilyNameIterator() const {
175    SkString familyName(fTestFont->fName);
176    SkString language("und"); //undetermined
177SkASSERT(0);  // incomplete
178    return nullptr;
179//     return new SkOTUtils::LocalizedStrings_SingleName(familyName, language);
180}
181
182class SkTestScalerContext : public SkScalerContext {
183public:
184    SkTestScalerContext(SkTestTypeface* face, const SkDescriptor* desc)
185        : SkScalerContext(face, desc)
186        , fFace(face)
187    {
188        fRec.getSingleMatrix(&fMatrix);
189        this->forceGenerateImageFromPath();
190    }
191
192    virtual ~SkTestScalerContext() {
193    }
194
195protected:
196    unsigned generateGlyphCount() override {
197        return fFace->onCountGlyphs();
198    }
199
200    uint16_t generateCharToGlyph(SkUnichar uni) override {
201        uint16_t glyph;
202        (void) fFace->onCharsToGlyphs((const void *) &uni, SkTypeface::kUTF16_Encoding, &glyph, 1);
203        return glyph;
204    }
205
206    void generateAdvance(SkGlyph* glyph) override {
207        fFace->getAdvance(glyph);
208
209        const SkVector advance = fMatrix.mapXY(SkFixedToScalar(glyph->fAdvanceX),
210                                               SkFixedToScalar(glyph->fAdvanceY));
211        glyph->fAdvanceX = SkScalarToFixed(advance.fX);
212        glyph->fAdvanceY = SkScalarToFixed(advance.fY);
213    }
214
215    void generateMetrics(SkGlyph* glyph) override {
216        fFace->getMetrics(glyph);
217
218        const SkVector advance = fMatrix.mapXY(SkFixedToScalar(glyph->fAdvanceX),
219                                               SkFixedToScalar(glyph->fAdvanceY));
220        glyph->fAdvanceX = SkScalarToFixed(advance.fX);
221        glyph->fAdvanceY = SkScalarToFixed(advance.fY);
222
223        SkPath path;
224        fFace->getPath(*glyph, &path);
225        path.transform(fMatrix);
226
227        SkRect storage;
228        const SkPaint paint;
229        const SkRect& newBounds = paint.doComputeFastBounds(path.getBounds(),
230                                                            &storage,
231                                                            SkPaint::kFill_Style);
232        SkIRect ibounds;
233        newBounds.roundOut(&ibounds);
234        glyph->fLeft = ibounds.fLeft;
235        glyph->fTop = ibounds.fTop;
236        glyph->fWidth = ibounds.width();
237        glyph->fHeight = ibounds.height();
238    }
239
240    void generateImage(const SkGlyph& glyph) override {
241        SkPath path;
242        fFace->getPath(glyph, &path);
243
244        SkBitmap bm;
245        bm.installPixels(SkImageInfo::MakeN32Premul(glyph.fWidth, glyph.fHeight),
246                            glyph.fImage, glyph.rowBytes());
247        bm.eraseColor(0);
248
249        SkCanvas canvas(bm);
250        canvas.translate(-SkIntToScalar(glyph.fLeft),
251                            -SkIntToScalar(glyph.fTop));
252        canvas.concat(fMatrix);
253        SkPaint paint;
254        paint.setAntiAlias(true);
255        canvas.drawPath(path, paint);
256    }
257
258    void generatePath(const SkGlyph& glyph, SkPath* path) override {
259        fFace->getPath(glyph, path);
260        path->transform(fMatrix);
261    }
262
263    void generateFontMetrics(SkPaint::FontMetrics* metrics) override {
264        fFace->getFontMetrics(metrics);
265        if (metrics) {
266            SkScalar scale = fMatrix.getScaleY();
267            metrics->fTop = SkScalarMul(metrics->fTop, scale);
268            metrics->fAscent = SkScalarMul(metrics->fAscent, scale);
269            metrics->fDescent = SkScalarMul(metrics->fDescent, scale);
270            metrics->fBottom = SkScalarMul(metrics->fBottom, scale);
271            metrics->fLeading = SkScalarMul(metrics->fLeading, scale);
272            metrics->fAvgCharWidth = SkScalarMul(metrics->fAvgCharWidth, scale);
273            metrics->fXMin = SkScalarMul(metrics->fXMin, scale);
274            metrics->fXMax = SkScalarMul(metrics->fXMax, scale);
275            metrics->fXHeight = SkScalarMul(metrics->fXHeight, scale);
276        }
277    }
278
279private:
280    SkTestTypeface*  fFace;
281    SkMatrix         fMatrix;
282};
283
284SkScalerContext* SkTestTypeface::onCreateScalerContext(const SkDescriptor* desc) const {
285    return new SkTestScalerContext(const_cast<SkTestTypeface*>(this), desc);
286}
287