| // Copyright 2019 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "third_party/blink/renderer/platform/fonts/win/dwrite_font_format_support.h" |
| |
| #include "third_party/skia/include/core/SkFontMgr.h" |
| #include "third_party/skia/include/core/SkFontStyle.h" |
| #include "third_party/skia/include/core/SkTypeface.h" |
| |
| namespace blink { |
| |
| bool DWriteVersionSupportsVariations() { |
| // We're instantiating a default typeface. The usage of legacyMakeTypeface() |
| // is intentional here to access a basic default font. Its implementation will |
| // ultimately use the first font face from the first family in the system font |
| // collection. Use this probe type face to ask Skia for the variation design |
| // position. Internally, Skia then tests whether the DWrite interfaces for |
| // accessing variable font information are available, in other words, if |
| // QueryInterface for IDWriteFontFace5 succeeds. If it doesn't it returns -1 |
| // and we know DWrite on this system does not support OpenType variations. If |
| // the response is 0 or larger, it means, DWrite was able to determine if this |
| // is a variable font or not and Variations are supported. |
| static bool variations_supported = []() { |
| auto fm(SkFontMgr::RefDefault()); |
| sk_sp<SkTypeface> probe_typeface = |
| fm->legacyMakeTypeface(nullptr, SkFontStyle()); |
| if (!probe_typeface) |
| return false; |
| int variation_design_position_result = |
| probe_typeface->getVariationDesignPosition(nullptr, 0); |
| |
| return variation_design_position_result > -1; |
| }(); |
| return variations_supported; |
| } |
| |
| } // namespace blink |
