// MIT License // Copyright (c) 2022 Tree Xie // Permission is hereby granted, free of charge, to any person obtaining a copy // of this software and associated documentation files (the "Software"), to deal // in the Software without restriction, including without limitation the rights // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell // copies of the Software, and to permit persons to whom the Software is // furnished to do so, subject to the following conditions: // The above copyright notice and this permission notice shall be included in all // copies or substantial portions of the Software. // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE // SOFTWARE. package charts import ( "errors" "sync" "github.com/golang/freetype/truetype" "github.com/wcharczuk/go-chart/v2/roboto" ) var fonts = sync.Map{} var ErrFontNotExists = errors.New("font is not exists") var defaultFontFamily = "defaultFontFamily" func init() { name := "roboto" _ = InstallFont(name, roboto.Roboto) font, _ := GetFont(name) SetDefaultFont(font) } // InstallFont installs the font for charts func InstallFont(fontFamily string, data []byte) error { font, err := truetype.Parse(data) if err != nil { return err } fonts.Store(fontFamily, font) return nil } // GetDefaultFont get default font func GetDefaultFont() (*truetype.Font, error) { return GetFont(defaultFontFamily) } // SetDefaultFont set default font func SetDefaultFont(font *truetype.Font) { if font == nil { return } fonts.Store(defaultFontFamily, font) } // GetFont get the font by font family func GetFont(fontFamily string) (*truetype.Font, error) { value, ok := fonts.Load(fontFamily) if !ok { return nil, ErrFontNotExists } f, ok := value.(*truetype.Font) if !ok { return nil, ErrFontNotExists } return f, nil }