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 '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 an entry using the 'blending' key (see File Structure above) 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.

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

• type - TEXTURE or CUBEMAP .
• data - description of the data source (for CUBEMAP type the 'data' contains 6 data sources, denoted by numbers from 0 to 6 (respectively X +, X-, Y +, Y-, Z +, Z-)). This can be set by any of the following:

1. From a file with keys 'path' and 'type = file';
2. Through a generator compiled into the engine. In this case, 'generator' (type = generator) and 'params' (generator parameters) keys are used. The actual version of the engine contains a generator to which a parameter of type 'Vec4' is set (not to be confused with 'vec4'). The generator can be used to create a single color texture - '[default] color'.

• sWrapping (optional). It is used for setting the type of texture filling (Repeat, MirroredRepeat, ClampToEdge) according to the S coordinate.
• tWrapping (optional). It is used for setting the type of texture filling (Repeat, MirroredRepeat, ClampToEdge) according to the T coordinate.
• filtering (optional). It is used for setting the texture filtering mode (Level0 - Level3).