Overview

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

Any of the directives can be included on its own line in shaders.properties. The directives can appear in any order. Below is an example shaders.properties file:

shaders.properties

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

screen = <empty> <profile> <empty> [SHADOWS] [LIGHTING] iScream uScream weAllScream forIceCream *
screen.SHADOWS = shadowMapResolution shadowFilter
screen.LIGHTING = SSAO SSR

User Accessible Shader Options

shaders.properties can be used to configure user accessible options, which appear in the “Shader Pack Settings” screen in Iris. More info can be found in the shader settings page. The following directives are available to control user accessible options in shaders.properties:

Directive	Description
screen	Controls which shader options are displayed in the “Shader Pack Settings” screen and how they are displayed
sliders	Controls which shader options should be displayed as sliders
profile	Defines profiles, i.e. pre-configured sets of user options selectable in the “Shader Pack Settings” screen

.lang files

.lang files can be used to add language specific overrides to option names and further customize how options appear in the “Shader Pack Settings” screen. The following directives are available in .lang files:

Directive	Description
option	Changes the visible name of an option
value	Changes the visible name of an option value
prefix	Adds a prefix to all values of an option
suffix	Adds a suffix to all values of an option
comment	Adds/changes the tooltip for an option

Internal Shader Settings

These directives control aspects of the shader pipeline. For example, they might enable/disable specific programs, change the order particles are rendered, override user clouds settings, etc.

Preprocessor directives can be used with internal shader settings, using macros based on shader options defined automatically. However, you cannot use #define or #include in shaders.properties.

Below is an index of shaders.properties directives available in Iris. Directives marked as Iris Exclusive are only available in Iris, and any unmarked uniforms is available in either Optifine or Iris.

Feature Flags

Feature flags are an Iris system to query the activation state of certain features. Some features require setting a feature flag to use. Feature flags can also be set as required, meaning the pack will only load if the system / Iris version supports the feature.

Directive	Description	Tag
iris.features.required	Sets the feature flags required to load the shader, enables those feature	Iris Exclusive
iris.features.optional	Sets the feature flags optional to load the shader, enables feature if supported	Iris Exclusive

Programs / Ordering

Directive	Description	Tag
particles.ordering	Controls the order in the pipeline particles will be rendered	Iris Exclusive
particles.before.deferred	Legacy option for particle ordering, replaced by particles.ordering
separateEntityDraws	Controls whether translucent entities/block entities are drawn before or after the deferred pass	Iris Exclusive
program.enabled	Allows programs to be disabled based on shader options
shadow.enabled	Enables or disables the shadow pass	Iris Exclusive
shadowTerrain	Sets whether terrain is rendered in the shadow pass
shadowTranslucent	Sets whether translucent terrain is rendered in the shadow pass
shadowEntities	Sets whether entities are rendered in the shadow pass
shadowPlayer	Sets whether the player is rendered in the shadow pass	Iris Exclusive
shadowBlockEntities	Sets whether block entities are rendered in the shadow pass
shadowLightBlockEntities	Sets whether block entities that emit light are rendered in the shadow pass	Iris Exclusive
skipAllRendering	Enables or disables most gbuffers passes	Iris Exclusive
voxelizeLightBlocks	Renders light blocks as an invisible quad in the shadow pass so that they can be voxelized	Iris Exclusive
indirect.pass	Allows you to dispatch a compute shader with the work group amount specified from a SSBO	Iris Exclusive
allowConcurrentCompute	Enables concurrent compute passes	Iris Exclusive

Features / Options

Directive	Description	Tag
clouds	Enables or disables vanilla cloud rendering
moon	Enables or disables rendering of the moon texture in gbuffers_skytextured
sun	Enables or disables rendering of the sun texture in gbuffers_skytextured
sky	Enables or disables rendering of vanilla sky in gbuffers_skybasic	Iris Exclusive
stars	Enables or disables rendering of stars in the sky in gbuffers_skybasic	Iris Exclusive
underwaterOverlay	Enables or disables the water texture overlay when the player is underwater
vignette	Enables or disables rendering of the vignette overlay
oldHandLight	Sets heldBlockLightValue to use whichever hand’s value is higher (for legacy support)
oldLighting	Enables the “old lighting”, which applies a lighting multiplier in the color attribute based on the block’s orientation
separateAo	Controls whether vanilla AO is stored in the RGB or A components of the color vertex attribute
supportsColorCorrection	Allows the shader to perform its own conversion to a different color space	Iris Exclusive
weather	Enables or disables weather (rain & snow) geometry and rain splash particles.	Iris Exclusive

Rendering

Directive	Description	Tag
alphaTest	Sets the alpha test function for cutout programs
blend	Sets the alpha blending parameters for a specific program, optionally per-buffer
scale	Defines a new viewport for a composite style program
flip	Enable or disable buffer flipping for a composite style program
size.buffer	Sets the resolution of a colortex buffer
backFace	Enables or disables back-face culling for each type of rendering
frustum.culling	Enables or disables frustum culling
occlusion.culling	Enables or disables occlusion culling	Iris Exclusive
shadow.culling	Controls culling in the shadow pass
rain.depth	Sets whether rain and snow write to the depth buffer
beacon.beam.depth	Sets whether beacon beams write to the depth buffer

Custom Uniforms

Custom uniforms can be used to create one-off values on the CPU, rather than having to compute them on the GPU. They are then uploaded to the GPU as uniforms, and are accessible from any shader program.

Directive	Description
uniform	Defines a custom uniform which is evaluated on the CPU and uploaded on program change
variable	Defines a variable to be used in a custom uniform

Textures / Buffers

These directives allow for setting up custom textures, images, and SSBOs. They are further described in the “Buffers” section (and linked here).

Directive	Description	Tag
texture	Creates a Custom texture, which binds an image/texture to an existing sampler
texture.noise	Loads an image from shader files into noisetex
customTexture	Creates an Enhanced Custom Texture, which binds an image/texture to a new sampler	Iris Exclusive
image	Creates a custom image with a sampler	Iris Exclusive
bufferObject	Creates a Shader Storage Buffer Object (SSBO)	Iris Exclusive