1 /*
2  * Copyright (c) 2024 Huawei Device Co., Ltd.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at
6  *
7  *     http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 
16 #ifndef LOADER_VERTEX_INPUT_DECLARATION_LOADER_H
17 #define LOADER_VERTEX_INPUT_DECLARATION_LOADER_H
18 
19 #include <base/containers/string.h>
20 #include <core/namespace.h>
21 #include <render/device/pipeline_state_desc.h>
22 #include <render/namespace.h>
23 
24 CORE_BEGIN_NAMESPACE()
25 class IFileManager;
26 CORE_END_NAMESPACE()
27 RENDER_BEGIN_NAMESPACE()
28 
29 /** Vertex input declaration loader.
30  * A class that can be used to load vertex input declaration from json structure.
31  */
32 class VertexInputDeclarationLoader final {
33 public:
34     /** Describes result of the parsing operation. */
35     struct LoadResult {
36         LoadResult() = default;
LoadResultfinal::LoadResult37         explicit LoadResult(const BASE_NS::string& error) : success(false), error(error) {}
38 
39         /** Indicates, whether the parsing operation is successful. */
40         bool success { true };
41 
42         /** In case of parsing error, contains the description of the error. */
43         BASE_NS::string error;
44     };
45 
46     /** Retrieve uri of the vertex input declaration.
47      * @return String view to uri of the vertex input declaration.
48      */
49     BASE_NS::string_view GetUri() const;
50 
51     /** Retrieve vertex input declaration.
52      * @return A view to vertex input declaration structure, as defined in the json file.
53      */
54     VertexInputDeclarationView GetVertexInputDeclarationView() const;
55 
56     /** Loads vertex input declaration from json string.
57      * @param jsonString A string containing valid json as content.
58      * @return A structure containing result for the parsing operation.
59      */
60     LoadResult Load(BASE_NS::string_view jsonString);
61 
62     /** Loads vertex input declaration from given uri, using file manager.
63      * @param fileManager A file manager to access the file in given uri.
64      * @param uri Uri to json file.
65      * @return A structure containing result for the parsing operation.
66      */
67     LoadResult Load(CORE_NS::IFileManager& fileManager, BASE_NS::string_view uri);
68 
69 private:
70     VertexInputDeclarationData vertexInputDeclarationData_;
71     BASE_NS::string uri_;
72 };
73 RENDER_END_NAMESPACE()
74 
75 #endif // LOADER_VERTEX_INPUT_DECLARATION_LOADER_H
76