OptionaltoneWhether the shading function should apply tone mapping to the resulting color and if so, which one. Default to 'Khronos'.
OptionaloutputIn which ColorSpace the output should be done. srgb should be used most of the time, except for some post processing effects that need input colors in linear space (such as bloom). Default to srgb.
OptionaladditionalOptional additional varyings to pass from the vertex shader to the fragment shader.
OptionalfragmentCustom fragment shader output structure members and returned values to use if needed. Useful when rendering to a Multiple Render Target for example.
Base parameters used to build a fragment shader.