Fabrice Di Meglio | 9f82b58 | 2011-03-08 12:02:59 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2011, The Android Open Source Project |
| 3 | * Copyright 2011, Google Inc. All rights reserved. |
| 4 | * |
| 5 | * Redistribution and use in source and binary forms, with or without |
| 6 | * modification, are permitted provided that the following conditions |
| 7 | * are met: |
| 8 | * * Redistributions of source code must retain the above copyright |
| 9 | * notice, this list of conditions and the following disclaimer. |
| 10 | * * Redistributions in binary form must reproduce the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer in the |
| 12 | * documentation and/or other materials provided with the distribution. |
| 13 | * |
| 14 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ``AS IS'' AND ANY |
| 15 | * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 16 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| 17 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
| 18 | * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| 19 | * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| 20 | * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
| 21 | * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY |
| 22 | * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 23 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| 24 | * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 25 | */ |
| 26 | |
| 27 | #include "HarfbuzzSkia.h" |
| 28 | |
| 29 | #include "SkFontHost.h" |
| 30 | |
| 31 | #include "SkPaint.h" |
| 32 | #include "SkPath.h" |
| 33 | #include "SkPoint.h" |
| 34 | #include "SkRect.h" |
| 35 | #include "SkTypeface.h" |
| 36 | |
Fabrice Di Meglio | eee49c6 | 2011-03-24 17:21:23 -0700 | [diff] [blame] | 37 | #include <utils/Log.h> |
| 38 | |
Fabrice Di Meglio | 9f82b58 | 2011-03-08 12:02:59 -0800 | [diff] [blame] | 39 | extern "C" { |
| 40 | #include "harfbuzz-shaper.h" |
| 41 | } |
| 42 | |
| 43 | // This file implements the callbacks which Harfbuzz requires by using Skia |
| 44 | // calls. See the Harfbuzz source for references about what these callbacks do. |
| 45 | |
| 46 | namespace android { |
| 47 | |
Fabrice Di Meglio | 9f82b58 | 2011-03-08 12:02:59 -0800 | [diff] [blame] | 48 | static void setupPaintWithFontData(SkPaint* paint, FontData* data) { |
Fabrice Di Meglio | 9f82b58 | 2011-03-08 12:02:59 -0800 | [diff] [blame] | 49 | paint->setTypeface(data->typeFace); |
Fabrice Di Meglio | eee49c6 | 2011-03-24 17:21:23 -0700 | [diff] [blame] | 50 | paint->setTextSize(data->textSize); |
| 51 | paint->setTextSkewX(data->textSkewX); |
| 52 | paint->setTextScaleX(data->textScaleX); |
| 53 | paint->setFlags(data->flags); |
| 54 | paint->setHinting(data->hinting); |
Fabrice Di Meglio | 9f82b58 | 2011-03-08 12:02:59 -0800 | [diff] [blame] | 55 | } |
| 56 | |
| 57 | static HB_Bool stringToGlyphs(HB_Font hbFont, const HB_UChar16* characters, hb_uint32 length, |
| 58 | HB_Glyph* glyphs, hb_uint32* glyphsSize, HB_Bool isRTL) |
| 59 | { |
| 60 | FontData* data = reinterpret_cast<FontData*>(hbFont->userData); |
| 61 | SkPaint paint; |
| 62 | setupPaintWithFontData(&paint, data); |
| 63 | |
| 64 | paint.setTextEncoding(SkPaint::kUTF16_TextEncoding); |
Fabrice Di Meglio | eee49c6 | 2011-03-24 17:21:23 -0700 | [diff] [blame] | 65 | uint16_t* skiaGlyphs = reinterpret_cast<uint16_t*>(glyphs); |
| 66 | int numGlyphs = paint.textToGlyphs(characters, length * sizeof(uint16_t), skiaGlyphs); |
Fabrice Di Meglio | 9f82b58 | 2011-03-08 12:02:59 -0800 | [diff] [blame] | 67 | |
| 68 | // HB_Glyph is 32-bit, but Skia outputs only 16-bit numbers. So our |
| 69 | // |glyphs| array needs to be converted. |
| 70 | for (int i = numGlyphs - 1; i >= 0; --i) { |
Fabrice Di Meglio | eee49c6 | 2011-03-24 17:21:23 -0700 | [diff] [blame] | 71 | glyphs[i] = skiaGlyphs[i]; |
Fabrice Di Meglio | 9f82b58 | 2011-03-08 12:02:59 -0800 | [diff] [blame] | 72 | } |
| 73 | |
| 74 | *glyphsSize = numGlyphs; |
| 75 | return 1; |
| 76 | } |
| 77 | |
| 78 | static void glyphsToAdvances(HB_Font hbFont, const HB_Glyph* glyphs, hb_uint32 numGlyphs, |
| 79 | HB_Fixed* advances, int flags) |
| 80 | { |
| 81 | FontData* data = reinterpret_cast<FontData*>(hbFont->userData); |
| 82 | SkPaint paint; |
| 83 | setupPaintWithFontData(&paint, data); |
| 84 | |
| 85 | paint.setTextEncoding(SkPaint::kGlyphID_TextEncoding); |
| 86 | |
| 87 | uint16_t* glyphs16 = new uint16_t[numGlyphs]; |
| 88 | if (!glyphs16) |
| 89 | return; |
| 90 | for (unsigned i = 0; i < numGlyphs; ++i) |
| 91 | glyphs16[i] = glyphs[i]; |
Fabrice Di Meglio | eee49c6 | 2011-03-24 17:21:23 -0700 | [diff] [blame] | 92 | SkScalar* scalarAdvances = reinterpret_cast<SkScalar*>(advances); |
| 93 | paint.getTextWidths(glyphs16, numGlyphs * sizeof(uint16_t), scalarAdvances); |
Fabrice Di Meglio | 9f82b58 | 2011-03-08 12:02:59 -0800 | [diff] [blame] | 94 | |
| 95 | // The |advances| values which Skia outputs are SkScalars, which are floats |
| 96 | // in Chromium. However, Harfbuzz wants them in 26.6 fixed point format. |
| 97 | // These two formats are both 32-bits long. |
| 98 | for (unsigned i = 0; i < numGlyphs; ++i) { |
Fabrice Di Meglio | eee49c6 | 2011-03-24 17:21:23 -0700 | [diff] [blame] | 99 | advances[i] = SkScalarToHBFixed(scalarAdvances[i]); |
| 100 | #if DEBUG_ADVANCES |
| 101 | LOGD("glyphsToAdvances -- advances[%d]=%d", i, advances[i]); |
| 102 | #endif |
Fabrice Di Meglio | 9f82b58 | 2011-03-08 12:02:59 -0800 | [diff] [blame] | 103 | } |
| 104 | delete glyphs16; |
| 105 | } |
| 106 | |
| 107 | static HB_Bool canRender(HB_Font hbFont, const HB_UChar16* characters, hb_uint32 length) |
| 108 | { |
| 109 | FontData* data = reinterpret_cast<FontData*>(hbFont->userData); |
| 110 | SkPaint paint; |
| 111 | setupPaintWithFontData(&paint, data); |
| 112 | |
| 113 | paint.setTextEncoding(SkPaint::kUTF16_TextEncoding); |
| 114 | |
| 115 | uint16_t* glyphs16 = new uint16_t[length]; |
| 116 | int numGlyphs = paint.textToGlyphs(characters, length * sizeof(uint16_t), glyphs16); |
| 117 | |
| 118 | bool result = true; |
| 119 | for (int i = 0; i < numGlyphs; ++i) { |
| 120 | if (!glyphs16[i]) { |
| 121 | result = false; |
| 122 | break; |
| 123 | } |
| 124 | } |
| 125 | delete glyphs16; |
| 126 | return result; |
| 127 | } |
| 128 | |
| 129 | static HB_Error getOutlinePoint(HB_Font hbFont, HB_Glyph glyph, int flags, hb_uint32 point, |
| 130 | HB_Fixed* xPos, HB_Fixed* yPos, hb_uint32* resultingNumPoints) |
| 131 | { |
| 132 | FontData* data = reinterpret_cast<FontData*>(hbFont->userData); |
| 133 | SkPaint paint; |
| 134 | setupPaintWithFontData(&paint, data); |
| 135 | |
| 136 | if (flags & HB_ShaperFlag_UseDesignMetrics) |
| 137 | // This is requesting pre-hinted positions. We can't support this. |
| 138 | return HB_Err_Invalid_Argument; |
| 139 | |
| 140 | paint.setTextEncoding(SkPaint::kGlyphID_TextEncoding); |
| 141 | uint16_t glyph16 = glyph; |
| 142 | SkPath path; |
| 143 | paint.getTextPath(&glyph16, sizeof(glyph16), 0, 0, &path); |
| 144 | uint32_t numPoints = path.getPoints(0, 0); |
| 145 | if (point >= numPoints) |
| 146 | return HB_Err_Invalid_SubTable; |
| 147 | SkPoint* points = reinterpret_cast<SkPoint*>(malloc(sizeof(SkPoint) * (point + 1))); |
| 148 | if (!points) |
| 149 | return HB_Err_Invalid_SubTable; |
| 150 | // Skia does let us get a single point from the path. |
| 151 | path.getPoints(points, point + 1); |
Fabrice Di Meglio | eee49c6 | 2011-03-24 17:21:23 -0700 | [diff] [blame] | 152 | *xPos = SkScalarToHBFixed(points[point].fX); |
| 153 | *yPos = SkScalarToHBFixed(points[point].fY); |
Fabrice Di Meglio | 9f82b58 | 2011-03-08 12:02:59 -0800 | [diff] [blame] | 154 | *resultingNumPoints = numPoints; |
| 155 | delete points; |
| 156 | |
| 157 | return HB_Err_Ok; |
| 158 | } |
| 159 | |
| 160 | static void getGlyphMetrics(HB_Font hbFont, HB_Glyph glyph, HB_GlyphMetrics* metrics) |
| 161 | { |
| 162 | FontData* data = reinterpret_cast<FontData*>(hbFont->userData); |
| 163 | SkPaint paint; |
| 164 | setupPaintWithFontData(&paint, data); |
| 165 | |
| 166 | paint.setTextEncoding(SkPaint::kGlyphID_TextEncoding); |
| 167 | uint16_t glyph16 = glyph; |
| 168 | SkScalar width; |
| 169 | SkRect bounds; |
| 170 | paint.getTextWidths(&glyph16, sizeof(glyph16), &width, &bounds); |
| 171 | |
Fabrice Di Meglio | eee49c6 | 2011-03-24 17:21:23 -0700 | [diff] [blame] | 172 | metrics->x = SkScalarToHBFixed(bounds.fLeft); |
| 173 | metrics->y = SkScalarToHBFixed(bounds.fTop); |
| 174 | metrics->width = SkScalarToHBFixed(bounds.width()); |
| 175 | metrics->height = SkScalarToHBFixed(bounds.height()); |
Fabrice Di Meglio | 9f82b58 | 2011-03-08 12:02:59 -0800 | [diff] [blame] | 176 | |
Fabrice Di Meglio | eee49c6 | 2011-03-24 17:21:23 -0700 | [diff] [blame] | 177 | metrics->xOffset = SkScalarToHBFixed(width); |
Fabrice Di Meglio | 9f82b58 | 2011-03-08 12:02:59 -0800 | [diff] [blame] | 178 | // We can't actually get the |y| correct because Skia doesn't export |
| 179 | // the vertical advance. However, nor we do ever render vertical text at |
| 180 | // the moment so it's unimportant. |
| 181 | metrics->yOffset = 0; |
| 182 | } |
| 183 | |
| 184 | static HB_Fixed getFontMetric(HB_Font hbFont, HB_FontMetric metric) |
| 185 | { |
| 186 | FontData* data = reinterpret_cast<FontData*>(hbFont->userData); |
| 187 | SkPaint paint; |
| 188 | setupPaintWithFontData(&paint, data); |
| 189 | |
| 190 | SkPaint::FontMetrics skiaMetrics; |
| 191 | paint.getFontMetrics(&skiaMetrics); |
| 192 | |
| 193 | switch (metric) { |
| 194 | case HB_FontAscent: |
Fabrice Di Meglio | eee49c6 | 2011-03-24 17:21:23 -0700 | [diff] [blame] | 195 | return SkScalarToHBFixed(-skiaMetrics.fAscent); |
Fabrice Di Meglio | 9f82b58 | 2011-03-08 12:02:59 -0800 | [diff] [blame] | 196 | // We don't support getting the rest of the metrics and Harfbuzz doesn't seem to need them. |
| 197 | default: |
| 198 | return 0; |
| 199 | } |
| 200 | return 0; |
| 201 | } |
| 202 | |
| 203 | const HB_FontClass harfbuzzSkiaClass = { |
| 204 | stringToGlyphs, |
| 205 | glyphsToAdvances, |
| 206 | canRender, |
| 207 | getOutlinePoint, |
| 208 | getGlyphMetrics, |
| 209 | getFontMetric, |
| 210 | }; |
| 211 | |
| 212 | HB_Error harfbuzzSkiaGetTable(void* voidface, const HB_Tag tag, HB_Byte* buffer, HB_UInt* len) |
| 213 | { |
Fabrice Di Meglio | 99cdc6a | 2011-12-06 14:27:12 -0800 | [diff] [blame] | 214 | return HB_Err_Invalid_Argument; |
Fabrice Di Meglio | 9f82b58 | 2011-03-08 12:02:59 -0800 | [diff] [blame] | 215 | } |
| 216 | |
| 217 | } // namespace android |