1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
|
/*
* Copyright 2016 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include <hb-ot.h>
#include "SkShaper.h"
#include "SkStream.h"
#include "SkTextBlob.h"
#include "SkTypeface.h"
static const int FONT_SIZE_SCALE = 512;
namespace {
struct HBFBlobDel {
void operator()(hb_blob_t* b) { hb_blob_destroy(b); }
};
std::unique_ptr<hb_blob_t, HBFBlobDel> stream_to_blob(std::unique_ptr<SkStreamAsset> asset) {
size_t size = asset->getLength();
std::unique_ptr<hb_blob_t, HBFBlobDel> blob;
if (const void* base = asset->getMemoryBase()) {
blob.reset(hb_blob_create((char*)base, size,
HB_MEMORY_MODE_READONLY, asset.release(),
[](void* p) { delete (SkStreamAsset*)p; }));
} else {
// SkDebugf("Extra SkStreamAsset copy\n");
SkAutoMalloc autoMalloc(size);
asset->read(autoMalloc.get(), size);
void* ptr = autoMalloc.get();
blob.reset(hb_blob_create((char*)autoMalloc.release(), size,
HB_MEMORY_MODE_READONLY, ptr, sk_free));
}
SkASSERT(blob);
hb_blob_make_immutable(blob.get());
return blob;
}
} // namespace
struct SkShaper::Impl {
struct HBFontDel {
void operator()(hb_font_t* f) { hb_font_destroy(f); }
};
std::unique_ptr<hb_font_t, HBFontDel> fHarfBuzzFont;
struct HBBufDel {
void operator()(hb_buffer_t* b) { hb_buffer_destroy(b); }
};
std::unique_ptr<hb_buffer_t, HBBufDel> fBuffer;
sk_sp<SkTypeface> fTypeface;
};
SkShaper::SkShaper(sk_sp<SkTypeface> tf) : fImpl(new Impl) {
fImpl->fTypeface = tf ? std::move(tf) : SkTypeface::MakeDefault();
int index;
std::unique_ptr<hb_blob_t, HBFBlobDel> blob(
stream_to_blob(std::unique_ptr<SkStreamAsset>(
fImpl->fTypeface->openStream(&index))));
struct HBFaceDel {
void operator()(hb_face_t* f) { hb_face_destroy(f); }
};
std::unique_ptr<hb_face_t, HBFaceDel> face(
hb_face_create(blob.get(), (unsigned)index));
SkASSERT(face);
if (!face) {
return;
}
hb_face_set_index(face.get(), (unsigned)index);
hb_face_set_upem(face.get(), fImpl->fTypeface->getUnitsPerEm());
fImpl->fHarfBuzzFont.reset(hb_font_create(face.get()));
SkASSERT(fImpl->fHarfBuzzFont);
hb_font_set_scale(fImpl->fHarfBuzzFont.get(), FONT_SIZE_SCALE, FONT_SIZE_SCALE);
hb_ot_font_set_funcs(fImpl->fHarfBuzzFont.get());
fImpl->fBuffer.reset(hb_buffer_create());
}
SkShaper::~SkShaper() {}
bool SkShaper::good() const { return fImpl->fHarfBuzzFont != nullptr; }
SkScalar SkShaper::shape(SkTextBlobBuilder* builder,
const SkPaint& srcPaint,
const char* utf8text,
size_t textBytes,
SkPoint point) const {
SkPaint paint(srcPaint);
paint.setTextEncoding(SkPaint::kGlyphID_TextEncoding);
paint.setTypeface(fImpl->fTypeface);
SkASSERT(builder);
hb_buffer_t* buffer = fImpl->fBuffer.get();
hb_buffer_add_utf8(buffer, utf8text, -1, 0, -1);
hb_buffer_guess_segment_properties(buffer);
hb_shape(fImpl->fHarfBuzzFont.get(), buffer, nullptr, 0);
unsigned len = hb_buffer_get_length(buffer);
if (len == 0) {
hb_buffer_clear_contents(buffer);
return 0;
}
hb_glyph_info_t* info = hb_buffer_get_glyph_infos(buffer, NULL);
hb_glyph_position_t* pos =
hb_buffer_get_glyph_positions(buffer, NULL);
auto runBuffer = builder->allocRunPos(paint, len);
double x = point.x();
double y = point.y();
double textSizeY = paint.getTextSize() / (double)FONT_SIZE_SCALE;
double textSizeX = textSizeY * paint.getTextScaleX();
for (unsigned i = 0; i < len; i++) {
runBuffer.glyphs[i] = info[i].codepoint;
reinterpret_cast<SkPoint*>(runBuffer.pos)[i] =
SkPoint::Make(x + pos[i].x_offset * textSizeX,
y - pos[i].y_offset * textSizeY);
x += pos[i].x_advance * textSizeX;
y += pos[i].y_advance * textSizeY;
}
hb_buffer_clear_contents(buffer);
return (SkScalar)x;
}
|
