| /* |
| * Copyright (c) 2012 Google Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are |
| * met: |
| * |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above |
| * copyright notice, this list of conditions and the following disclaimer |
| * in the documentation and/or other materials provided with the |
| * distribution. |
| * * Neither the name of Google Inc. nor the names of its |
| * contributors may be used to endorse or promote products derived from |
| * this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #define LOG_TAG "TextLayoutCache" |
| |
| #include "HarfBuzzNGFaceSkia.h" |
| |
| #include <stdlib.h> |
| |
| #include <log/log.h> |
| |
| #include <SkPaint.h> |
| #include <SkPath.h> |
| #include <SkPoint.h> |
| #include <SkRect.h> |
| #include <SkTypeface.h> |
| |
| #include <hb.h> |
| |
| namespace android { |
| |
| static const bool kDebugGlyphs = false; |
| |
| // Our implementation of the callbacks which Harfbuzz requires by using Skia |
| // calls. See the Harfbuzz source for references about what these callbacks do. |
| |
| struct HarfBuzzFontData { |
| explicit HarfBuzzFontData(SkPaint* paint) : m_paint(paint) { } |
| SkPaint* m_paint; |
| }; |
| |
| static void SkiaGetGlyphWidthAndExtents(SkPaint* paint, hb_codepoint_t codepoint, hb_position_t* width, hb_glyph_extents_t* extents) |
| { |
| ALOG_ASSERT(codepoint <= 0xFFFF); |
| paint->setTextEncoding(kGlyphID_SkTextEncoding); |
| |
| SkScalar skWidth; |
| SkRect skBounds; |
| uint16_t glyph = codepoint; |
| |
| paint->getTextWidths(&glyph, sizeof(glyph), &skWidth, &skBounds); |
| if (kDebugGlyphs) { |
| ALOGD("returned glyph for %i: width = %f", codepoint, skWidth); |
| } |
| if (width) |
| *width = SkScalarToHBFixed(skWidth); |
| if (extents) { |
| // Invert y-axis because Skia is y-grows-down but we set up harfbuzz to be y-grows-up. |
| extents->x_bearing = SkScalarToHBFixed(skBounds.fLeft); |
| extents->y_bearing = SkScalarToHBFixed(-skBounds.fTop); |
| extents->width = SkScalarToHBFixed(skBounds.width()); |
| extents->height = SkScalarToHBFixed(-skBounds.height()); |
| } |
| } |
| |
| static hb_bool_t harfbuzzGetGlyph(hb_font_t* hbFont, void* fontData, hb_codepoint_t unicode, hb_codepoint_t variationSelector, hb_codepoint_t* glyph, void* userData) |
| { |
| HarfBuzzFontData* hbFontData = reinterpret_cast<HarfBuzzFontData*>(fontData); |
| SkPaint* paint = hbFontData->m_paint; |
| paint->setTextEncoding(kUTF32_SkTextEncoding); |
| |
| if (unicode > 0x10ffff) { |
| unicode = 0xfffd; |
| } |
| SkUnichar unichar = unicode; |
| |
| uint16_t glyph16; |
| paint->textToGlyphs(&unichar, sizeof(unichar), &glyph16); |
| *glyph = glyph16; |
| return !!*glyph; |
| } |
| |
| static hb_position_t harfbuzzGetGlyphHorizontalAdvance(hb_font_t* hbFont, void* fontData, hb_codepoint_t glyph, void* userData) |
| { |
| HarfBuzzFontData* hbFontData = reinterpret_cast<HarfBuzzFontData*>(fontData); |
| hb_position_t advance = 0; |
| |
| SkiaGetGlyphWidthAndExtents(hbFontData->m_paint, glyph, &advance, 0); |
| return advance; |
| } |
| |
| static hb_bool_t harfbuzzGetGlyphHorizontalOrigin(hb_font_t* hbFont, void* fontData, hb_codepoint_t glyph, hb_position_t* x, hb_position_t* y, void* userData) |
| { |
| // Just return true, following the way that Harfbuzz-FreeType |
| // implementation does. |
| return true; |
| } |
| |
| static hb_bool_t harfbuzzGetGlyphExtents(hb_font_t* hbFont, void* fontData, hb_codepoint_t glyph, hb_glyph_extents_t* extents, void* userData) |
| { |
| HarfBuzzFontData* hbFontData = reinterpret_cast<HarfBuzzFontData*>(fontData); |
| |
| SkiaGetGlyphWidthAndExtents(hbFontData->m_paint, glyph, 0, extents); |
| return true; |
| } |
| |
| static hb_font_funcs_t* harfbuzzSkiaGetFontFuncs() |
| { |
| static hb_font_funcs_t* harfbuzzSkiaFontFuncs = 0; |
| |
| // We don't set callback functions which we can't support. |
| // Harfbuzz will use the fallback implementation if they aren't set. |
| if (!harfbuzzSkiaFontFuncs) { |
| harfbuzzSkiaFontFuncs = hb_font_funcs_create(); |
| hb_font_funcs_set_glyph_func(harfbuzzSkiaFontFuncs, harfbuzzGetGlyph, 0, 0); |
| hb_font_funcs_set_glyph_h_advance_func(harfbuzzSkiaFontFuncs, harfbuzzGetGlyphHorizontalAdvance, 0, 0); |
| hb_font_funcs_set_glyph_h_origin_func(harfbuzzSkiaFontFuncs, harfbuzzGetGlyphHorizontalOrigin, 0, 0); |
| hb_font_funcs_set_glyph_extents_func(harfbuzzSkiaFontFuncs, harfbuzzGetGlyphExtents, 0, 0); |
| hb_font_funcs_make_immutable(harfbuzzSkiaFontFuncs); |
| } |
| return harfbuzzSkiaFontFuncs; |
| } |
| |
| hb_blob_t* harfbuzzSkiaReferenceTable(hb_face_t* face, hb_tag_t tag, void* userData) |
| { |
| SkTypeface* typeface = reinterpret_cast<SkTypeface*>(userData); |
| |
| const size_t tableSize = typeface->getTableSize(tag); |
| if (!tableSize) |
| return 0; |
| |
| char* buffer = reinterpret_cast<char*>(malloc(tableSize)); |
| if (!buffer) |
| return 0; |
| size_t actualSize = typeface->getTableData(tag, 0, tableSize, buffer); |
| if (tableSize != actualSize) { |
| free(buffer); |
| return 0; |
| } |
| |
| return hb_blob_create(const_cast<char*>(buffer), tableSize, |
| HB_MEMORY_MODE_WRITABLE, buffer, free); |
| } |
| |
| static void destroyHarfBuzzFontData(void* data) { |
| delete (HarfBuzzFontData*)data; |
| } |
| |
| hb_font_t* createFont(hb_face_t* face, SkPaint* paint, float sizeX, float sizeY) { |
| hb_font_t* font = hb_font_create(face); |
| |
| // Note: this needs to be reworked when we do subpixels |
| int x_ppem = floor(sizeX + 0.5); |
| int y_ppem = floor(sizeY + 0.5); |
| hb_font_set_ppem(font, x_ppem, y_ppem); |
| hb_font_set_scale(font, HBFloatToFixed(sizeX), HBFloatToFixed(sizeY)); |
| |
| HarfBuzzFontData* data = new HarfBuzzFontData(paint); |
| hb_font_set_funcs(font, harfbuzzSkiaGetFontFuncs(), data, destroyHarfBuzzFontData); |
| |
| return font; |
| } |
| |
| } // namespace android |