Material File Format/en

Scope

Material is part of the W4 Engine Material System. The values of the shader parameters that will be used by default for all instances of this material, as well as the instructions for the render (blending) and texture (wrapping and filtering) can be set in the material file (.mat).

Detailed Description

File Structure

Example .mat file:

 {
     "vertexFile" : "<path from the project root directory to the vertex shader file (.vs)>",
     "fragmentFile" : "<path from the project root directory to the fragment shader file(.fs)>",
     ["blending" : <enable blending (true/false)>,]
     ["blending" : {"src" : "<blending function for the result of your shader>", "dst" : "<blending function for background>"},]
     "params" : {
         "texture0": {"type": "TEXTURE", "data": {"path": "<path from the project root directory to the texture file>", "type": "file"}[, "sWrapping": "{Repeat|MirroredRepeat|ClampToEdge}"][, "tWrapping" : "{Repeat|MirroredRepeat|ClampToEdge}"][, "filtering": "{Level0|Level1|Level2|Level3}"]},
         "texture1": {"type": "TEXTURE", "data": {"generator": "[default] color", "params": {"type": "Vec4", "value": { "x": 1.0, "y": 1.0 , "z": 1.0, "w": 1.0 }}, "type": "generator"}},
         "cubemap0": {"type": "CUBEMAP", "data": {
                 "0": {"path": "<path from the project root directory to the X+ texture file>", "type": "file"},
                 "1": {"path": "<path from the project root directory to the X- texture file>", "type": "file"},
                 "2": {"path": "<path from the project root directory to the Y+ texture file>", "type": "file"},
                 "3": {"path": "<path from the project root directory to the Y- texture file>", "type": "file"},
                 "4": {"path": "<path from the project root directory to the Z+ texture file>", "type": "file"},
                 "5": {"path": "<path from the project root directory to the Z- texture file>", "type": "file"}
             }
         },
         "intParam": { "type": "INT", "data": -42 },
         "floatParam": { "type": "BOOL", "data": 3.14159259 },
         "boolParam": { "type": "BOOL", "data": true },
         "vec2Param": { "type": "VEC2", "data": { "x": 0.1, "y": 0.2 }},
         "vec3Param": { "type": "VEC3", "data": { "x": 0.1, "y": 0.2 , "z": 0.3 }},
         "vec4Param": { "type": "VEC4", "data": { "x": 0.1, "y": 0.2 , "z": 0.3, "w": 0.4 }}
     }
 }

The following values ​​are mandatory:

• vertexFile
• fragmentFile

Everything else is optional.

Hints

In order not to set the same parameters again and again, you can set default values for any parameter in the material file. These parameters will be set for each new MatInstance. The following parameter types are supported: INT, FLOAT, BOOL, VEC2, VEC3, VEC4, TEXTURE, СUBEMAP.

• By default, the transparency of the material is disabled. It can be enabled in two ways:

1. Set the blending key to true. In this case, the SRC_ALPHA functions for the shader result and ONE_MINUS_SRC_ALPHA for the background are set for the material.
2. Define a record with a 'blending' key containing src and dst values, respectively. Possible values are: ZERO, ONE, SRC_COLOR, ONE_MINUS_SRC_COLOR, DST_COLOR, ONE_MINUS_DST_COLOR, SRC_ALPHA, ONE_MINUS_SRC_ALPHA, DST_ALPHA, ONE_MINUS_DST_ALPHA, CONSTANT_COLOR, ONE_MINUS_CONSTANT_COLOR, CONSTANT_ALPHA, ONE_MINUS_CONSTANT_ALPHA, SRC_ALPHA_SATURATE.

• The entry for the TEXTURE and CUBEMAP types consists of the following key-value pairs:

1. type - TEXTURE или CUBEMAP .
2. data - описание источника данных. Им может быть как файл (с ключами path и type=file), так и генератор вкомпилированный в движок (с ключами generator, type=generator и params (параметры генератора)). На момент написания статьи доступен только один генератор с параметром типа Vec4 (регистр именно такой, т.к. это тип параметра генератора (Variant), а не параметра материала) для создания текстуры одного цвета - "[default] color". Для типа CUBEMAP data содержит 6 источников данных, обозначаемых цифрами от 0 до 6 (соответственно X+, X-, Y+, Y-, Z+, Z-) ;
3. Опциональное поле sWrapping для задания типа заполнения текстурой (Repeat, MirroredRepeat, ClampToEdge) по координате S .
4. Опциональное поле tWrapping для задания типа заполнения текстурой (Repeat, MirroredRepeat, ClampToEdge) по координате T .
5. Опциональное поле filtering для задания режима фильтрации текстуры (Level0 - Level3).