Skip to content
Iris Docs

Overview: shaders.properties

The shaders.properties is a text file placed in the shaders folder that allows for configuring many options of a shaderpack. This file has two main purposes:

  1. Configuring and displaying user accessible shader options
  2. Configuring internal shader settings

Internal Shader Settings

The file can contain any of the properties described in this section, in any order. These properties control both aspects of the shader itself, and allow for defining user accessible shader options. For example:

iris.features.required = CUSTOM_IMAGES COMPUTE_SHADERS SSBO REVERSED_CULLING
separateEntityDraws = true
shadow.culling = reversed
image.testImage = testSampler rgba rgba8 float false true 1.0 1.0

Preprocessor directives can be used inside this file based on shader option macros, which are defined automatically. However, you cannot use #define or #include in shaders.properties.

Shader Options

Iris lets you use preprocessor directives to define user options. These macros should be defined in the shader files using #define. The value of an option can be checked in shader files with #ifdef, #ifndef, #if, etc. The option must be defined in all files which it is used in, and if it is defined in multiple files it must be defined identically in all files. Lastly, add the option name to screen list to add the shader option to the “Shader Pack Settings” screen. sliders and profile can further be used to control the layout of these options.

Boolean Option

A boolean option can be defined and checked in shader code with like the following:

#define optionName //description
//#define optionName //description


#ifdef optionName
  // code here only if optionName is "on"
#endif


#ifndef optionName
  // code here only if optionName is "off"
#endif

The option will be “on” (defined) by default, however commenting out the #define line will keep the option but make the default value “off” (not defined).

Optionally, a comment after the macro can be used to add a description to the option, shown when hovering over the option in the “Shader Pack Settings” screen.

#if defined can be used to check multiple options in one line (for example see below). However for Iris/Optifine to recognize a boolean option, it must be checked at least once using #ifdef or #ifndef.

#if defined option1 && defined option2
  // code here only if option1 and option2 are "on"
#endif

Numerical/Other Option

Any non-boolean option, such as a float or int, can be defined by specifying a value with the define:

#define optionName <defaultValue> // [<value1> <value2> ...] description


#if optionName == <intValue>
#endif

A comment should be placed after the macro, and the possible values for the option should be placed square brackets directly after the comment starts. The values should be separated by spaces only. Any text after the values list will be treated as a description for the option, shown when hovering over the option in the “Shader Pack Settings” screen.

These options can be used directly in shader code like a variable, and will be replaced with the option’s value before compilation. Additionally, int options only can be checked using #if.

Constants

Iris/Optifine define numerous constants to control certain settings (see the Constants section). If a value list is added in a comment after the declaration of a numeric const, it can be added to the shaders screen like a shader define option. For example:

const int shadowMapResolution = 2048; // [512 1024 2048 4096]