| /* |
| * Copyright 2023 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package androidx.compose.ui.unit |
| |
| import androidx.compose.runtime.Immutable |
| import androidx.compose.runtime.Stable |
| import androidx.compose.ui.ExperimentalComposeUiApi |
| import androidx.compose.ui.unit.fontscaling.FontScaleConverterFactory |
| import androidx.compose.ui.unit.internal.JvmDefaultWithCompatibility |
| |
| /** |
| * Converts [TextUnit] to [Dp] and vice-versa. |
| * |
| * Note that the converter can't be cached in the interface itself. FontScaleConverterFactory |
| * already caches the tables, but it still does a a map lookup for each conversion. If you are |
| * implementing this interface, you should cache your own converter for additional speed. |
| */ |
| @Immutable |
| @JvmDefaultWithCompatibility |
| @OptIn(ExperimentalComposeUiApi::class) |
| actual interface FontScaling { |
| /** |
| * Current user preference for the scaling factor for fonts. |
| */ |
| @Stable |
| actual val fontScale: Float |
| |
| /** |
| * Convert [Dp] to Sp. Sp is used for font size, etc. |
| */ |
| @Stable |
| actual fun Dp.toSp(): TextUnit { |
| if (!FontScaleConverterFactory.isNonLinearFontScalingActive(fontScale) || |
| DisableNonLinearFontScalingInCompose) { |
| return (value / fontScale).sp |
| } |
| |
| val converter = FontScaleConverterFactory.forScale(fontScale) |
| return (converter?.convertDpToSp(value) ?: (value / fontScale)).sp |
| } |
| |
| /** |
| * Convert Sp to [Dp]. |
| * @throws IllegalStateException if TextUnit other than SP unit is specified. |
| */ |
| @Stable |
| actual fun TextUnit.toDp(): Dp { |
| check(type == TextUnitType.Sp) { "Only Sp can convert to Px" } |
| if (!FontScaleConverterFactory.isNonLinearFontScalingActive(fontScale) || |
| DisableNonLinearFontScalingInCompose) { |
| return Dp(value * fontScale) |
| } |
| |
| val converter = FontScaleConverterFactory.forScale(fontScale) |
| return if (converter == null) Dp(value * fontScale) else Dp(converter.convertSpToDp(value)) |
| } |
| } |
