1 /*
2 * Copyright 2010 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 "GrTextContext.h"
9 #include "GrContext.h"
10
11 #include "SkAutoKern.h"
12 #include "SkGlyphCache.h"
13 #include "GrFontScaler.h"
14
GrTextContext(GrContext * context,const SkDeviceProperties & properties)15 GrTextContext::GrTextContext(GrContext* context, const SkDeviceProperties& properties) :
16 fContext(context), fDeviceProperties(properties), fDrawTarget(NULL) {
17 }
18
init(const GrPaint & grPaint,const SkPaint & skPaint)19 void GrTextContext::init(const GrPaint& grPaint, const SkPaint& skPaint) {
20 const GrClipData* clipData = fContext->getClip();
21
22 SkRect devConservativeBound;
23 clipData->fClipStack->getConservativeBounds(
24 -clipData->fOrigin.fX,
25 -clipData->fOrigin.fY,
26 fContext->getRenderTarget()->width(),
27 fContext->getRenderTarget()->height(),
28 &devConservativeBound);
29
30 devConservativeBound.roundOut(&fClipRect);
31
32 fDrawTarget = fContext->getTextTarget();
33
34 fPaint = grPaint;
35 fSkPaint = skPaint;
36 }
37
38 //*** change to output positions?
MeasureText(SkGlyphCache * cache,SkDrawCacheProc glyphCacheProc,const char text[],size_t byteLength,SkVector * stopVector)39 void GrTextContext::MeasureText(SkGlyphCache* cache, SkDrawCacheProc glyphCacheProc,
40 const char text[], size_t byteLength, SkVector* stopVector) {
41 SkFixed x = 0, y = 0;
42 const char* stop = text + byteLength;
43
44 SkAutoKern autokern;
45
46 while (text < stop) {
47 // don't need x, y here, since all subpixel variants will have the
48 // same advance
49 const SkGlyph& glyph = glyphCacheProc(cache, &text, 0, 0);
50
51 x += autokern.adjust(glyph) + glyph.fAdvanceX;
52 y += glyph.fAdvanceY;
53 }
54 stopVector->set(SkFixedToScalar(x), SkFixedToScalar(y));
55
56 SkASSERT(text == stop);
57 }
58
GlyphCacheAuxProc(void * data)59 static void GlyphCacheAuxProc(void* data) {
60 GrFontScaler* scaler = (GrFontScaler*)data;
61 SkSafeUnref(scaler);
62 }
63
GetGrFontScaler(SkGlyphCache * cache)64 GrFontScaler* GrTextContext::GetGrFontScaler(SkGlyphCache* cache) {
65 void* auxData;
66 GrFontScaler* scaler = NULL;
67
68 if (cache->getAuxProcData(GlyphCacheAuxProc, &auxData)) {
69 scaler = (GrFontScaler*)auxData;
70 }
71 if (NULL == scaler) {
72 scaler = SkNEW_ARGS(GrFontScaler, (cache));
73 cache->setAuxProc(GlyphCacheAuxProc, scaler);
74 }
75
76 return scaler;
77 }
78