1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45
// Copyright 2017-2018 Matthew D. Michelotti
//
// 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.
//! Traits related to asset enums that are generated by "gate_build".
//!
//! The user is not expected to implement these traits themselves directly.
//! Rather, the generated code from "gate_build" will implement these traits.
//! Gate build will generate four enums: `SpriteId`, `MusicId`, and `SoundId`,
//! that implement `IdU16`.
//! It will also generate a collection type `AssetId` that implements `AppAssetId`.
/// A value that can be converted to a `u16` ID, implemented by asset enums.
pub trait IdU16: Sized {
/// Converts self to a `u16` ID.
///
/// This will be value between `0` (inclusive) and `Self::count()` (exclusive).
fn id_u16(self) -> u16;
/// Returns the number of IDs in this enum.
fn count() -> u16;
/// Converts a `u16` ID to the asset enum value, or `None` if `id >= Self::count()`
fn from_u16(id: u16) -> Option<Self>;
}
/// A convenience collection of all asset ID types.
pub trait AppAssetId {
/// Sprite asset enum
type Sprite: IdU16;
/// Music asset enum
type Music: IdU16;
/// Sound asset enum
type Sound: IdU16;
}