SkTestScalerContext.cpp revision c50acf2321d7a934c80d754e9cbe936dfb8eb4cc 
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(NULL)
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        SkDELETE(fPaths[index]);
39    }
40    SkDELETE_ARRAY(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 = SkNEW_ARRAY(SkPath*, fCharCodesCount);
82    for (unsigned index = 0; index < fCharCodesCount; ++index) {
83        SkPath* path = SkNEW(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        fPaths[index] = path;
112    }
113}
114
115SkTestTypeface::SkTestTypeface(SkTestFont* testFont, const SkFontStyle& style)
116    : SkTypeface(style, SkTypefaceCache::NewFontID(), false)
117    , fTestFont(testFont) {
118}
119
120void SkTestTypeface::getAdvance(SkGlyph* glyph) {
121    glyph->fAdvanceX = fTestFont->fWidths[glyph->getGlyphID()];
122    glyph->fAdvanceY = 0;
123}
124
125void SkTestTypeface::getFontMetrics(SkPaint::FontMetrics* metrics) {
126    *metrics = fTestFont->fMetrics;
127}
128
129void SkTestTypeface::getMetrics(SkGlyph* glyph) {
130    glyph->fAdvanceX = fTestFont->fWidths[glyph->getGlyphID()];
131    glyph->fAdvanceY = 0;
132}
133
134void SkTestTypeface::getPath(const SkGlyph& glyph, SkPath* path) {
135    *path = *fTestFont->fPaths[glyph.getGlyphID()];
136}
137
138void SkTestTypeface::onFilterRec(SkScalerContextRec* rec) const {
139    rec->setHinting(SkPaint::kNo_Hinting);
140}
141
142SkAdvancedTypefaceMetrics* SkTestTypeface::onGetAdvancedTypefaceMetrics(
143                                PerGlyphInfo ,
144                                const uint32_t* glyphIDs,
145                                uint32_t glyphIDsCount) const {
146// pdf only
147    SkAdvancedTypefaceMetrics* info = new SkAdvancedTypefaceMetrics;
148    info->fFontName.set(fTestFont->fName);
149    info->fType = SkAdvancedTypefaceMetrics::kOther_Font;
150    info->fFlags = SkAdvancedTypefaceMetrics::kEmpty_FontFlag;
151    info->fLastGlyphID = SkToU16(onCountGlyphs() - 1);
152    info->fEmSize = 0;
153    info->fStyle = 0;
154    info->fItalicAngle = 0;
155    info->fAscent = 0;
156    info->fDescent = 0;
157    info->fStemV = 0;
158    info->fCapHeight = 0;
159    info->fBBox = SkIRect::MakeEmpty();
160    return info;
161}
162
163void SkTestTypeface::onGetFontDescriptor(SkFontDescriptor* desc, bool* isLocal) const {
164    desc->setFamilyName(fTestFont->fName);
165    *isLocal = false;
166}
167
168int SkTestTypeface::onCharsToGlyphs(const void* chars, Encoding encoding,
169                            uint16_t glyphs[], int glyphCount) const {
170    SkASSERT(encoding == kUTF16_Encoding);
171    for (int index = 0; index < glyphCount; ++index) {
172        SkUnichar ch = ((SkUnichar*) chars)[index];
173        glyphs[index] = fTestFont->codeToIndex(ch);
174    }
175    return glyphCount;
176}
177
178void SkTestTypeface::onGetFamilyName(SkString* familyName) const {
179    *familyName = fTestFont->fName;
180}
181
182SkTypeface::LocalizedStrings* SkTestTypeface::onCreateFamilyNameIterator() const {
183    SkString familyName(fTestFont->fName);
184    SkString language("und"); //undetermined
185SkASSERT(0);  // incomplete
186    return NULL;
187//     return new SkOTUtils::LocalizedStrings_SingleName(familyName, language);
188}
189
190class SkTestScalerContext : public SkScalerContext {
191public:
192    SkTestScalerContext(SkTestTypeface* face, const SkDescriptor* desc)
193        : SkScalerContext(face, desc)
194        , fFace(face)
195    {
196        fRec.getSingleMatrix(&fMatrix);
197        this->forceGenerateImageFromPath();
198    }
199
200    virtual ~SkTestScalerContext() {
201    }
202
203protected:
204    unsigned generateGlyphCount() override {
205        return fFace->onCountGlyphs();
206    }
207
208    uint16_t generateCharToGlyph(SkUnichar uni) override {
209        uint16_t glyph;
210        (void) fFace->onCharsToGlyphs((const void *) &uni, SkTypeface::kUTF16_Encoding, &glyph, 1);
211        return glyph;
212    }
213
214    void generateAdvance(SkGlyph* glyph) override {
215        fFace->getAdvance(glyph);
216
217        const SkVector advance = fMatrix.mapXY(SkFixedToScalar(glyph->fAdvanceX),
218                                               SkFixedToScalar(glyph->fAdvanceY));
219        glyph->fAdvanceX = SkScalarToFixed(advance.fX);
220        glyph->fAdvanceY = SkScalarToFixed(advance.fY);
221    }
222
223    void generateMetrics(SkGlyph* glyph) override {
224        fFace->getMetrics(glyph);
225
226        const SkVector advance = fMatrix.mapXY(SkFixedToScalar(glyph->fAdvanceX),
227                                               SkFixedToScalar(glyph->fAdvanceY));
228        glyph->fAdvanceX = SkScalarToFixed(advance.fX);
229        glyph->fAdvanceY = SkScalarToFixed(advance.fY);
230
231        SkPath path;
232        fFace->getPath(*glyph, &path);
233        path.transform(fMatrix);
234
235        SkRect storage;
236        const SkPaint paint;
237        const SkRect& newBounds = paint.doComputeFastBounds(path.getBounds(),
238                                                            &storage,
239                                                            SkPaint::kFill_Style);
240        SkIRect ibounds;
241        newBounds.roundOut(&ibounds);
242        glyph->fLeft = ibounds.fLeft;
243        glyph->fTop = ibounds.fTop;
244        glyph->fWidth = ibounds.width();
245        glyph->fHeight = ibounds.height();
246    }
247
248    void generateImage(const SkGlyph& glyph) override {
249        SkPath path;
250        fFace->getPath(glyph, &path);
251
252        SkBitmap bm;
253        bm.installPixels(SkImageInfo::MakeN32Premul(glyph.fWidth, glyph.fHeight),
254                            glyph.fImage, glyph.rowBytes());
255        bm.eraseColor(0);
256
257        SkCanvas canvas(bm);
258        canvas.translate(-SkIntToScalar(glyph.fLeft),
259                            -SkIntToScalar(glyph.fTop));
260        canvas.concat(fMatrix);
261        SkPaint paint;
262        paint.setAntiAlias(true);
263        canvas.drawPath(path, paint);
264    }
265
266    void generatePath(const SkGlyph& glyph, SkPath* path) override {
267        fFace->getPath(glyph, path);
268        path->transform(fMatrix);
269    }
270
271    void generateFontMetrics(SkPaint::FontMetrics* metrics) override {
272        fFace->getFontMetrics(metrics);
273        if (metrics) {
274            SkScalar scale = fMatrix.getScaleY();
275            metrics->fTop = SkScalarMul(metrics->fTop, scale);
276            metrics->fAscent = SkScalarMul(metrics->fAscent, scale);
277            metrics->fDescent = SkScalarMul(metrics->fDescent, scale);
278            metrics->fBottom = SkScalarMul(metrics->fBottom, scale);
279            metrics->fLeading = SkScalarMul(metrics->fLeading, scale);
280            metrics->fAvgCharWidth = SkScalarMul(metrics->fAvgCharWidth, scale);
281            metrics->fXMin = SkScalarMul(metrics->fXMin, scale);
282            metrics->fXMax = SkScalarMul(metrics->fXMax, scale);
283            metrics->fXHeight = SkScalarMul(metrics->fXHeight, scale);
284        }
285    }
286
287private:
288    SkTestTypeface*  fFace;
289    SkMatrix         fMatrix;
290};
291
292SkScalerContext* SkTestTypeface::onCreateScalerContext(const SkDescriptor* desc) const {
293    return SkNEW_ARGS(SkTestScalerContext, (const_cast<SkTestTypeface*>(this), desc));
294}
295