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#########################
OMWFX Language Reference
#########################
Overview
########
Shaders are written in a OpenMW specific `` *.omwfx `` format. This is a light
wrapper around GLSL, so a basic understanding of GLSL should be acquired before
attempting to write any shaders. Every shader must be contained within a single
`` *.omwfx `` file, `` #include `` directives are currently unsupported.
By default, all shaders only guarantee support of GLSL 120 features. To target a
newer GLSL version, you must specify it in the `technique`_ block properties. If
the specified version is not supported on the target machine, the shader will
not load.
Reserved Keywords
#################
GLSL doesn't support namespaces, instead reserved prefixes are used. Do not
attempt to name anything starting with `` _ `` or `` omw `` , this will cause
name clashes.
Builtin Samplers
################
+------------------+---------------------------+---------------------------------------------+
| GLSL Type | Name | Description |
+==================+===========================+=============================================+
| sampler2D[Array] |`` omw_SamplerLastShader `` | Color output of the last shader |
+------------------+---------------------------+---------------------------------------------+
| sampler2D[Array] |`` omw_SamplerLastPass `` | Color output of the last pass |
+------------------+---------------------------+---------------------------------------------+
| sampler2D[Array] |`` omw_SamplerDepth `` | Non-linear normalized depth |
+------------------+---------------------------+---------------------------------------------+
| sampler2D[Array] |`` omw_SamplerNormals `` | Normalized world-space normals [0, 1] |
+------------------+---------------------------+---------------------------------------------+
These are included in a common header in every pass, they do not need to be re-defined.
It is recommended to use the accessor functions to retrieve the sampler value.
OpenMW supports multiview rendering, so these samplers will either be a
`` sampler2D `` or `` sampler2DArray `` . If you want more control over how you
sample textures, use the `` OMW_MULTIVIEW `` macro to determine the appropriate functions to use.
Builtin Uniforms
################
+-------------+------------------------------+--------------------------------------------------+
| GLSL Type | Name | Description |
+=============+==============================+==================================================+
| mat4 | `` omw.projectionMatrix `` | The camera's projection matrix |
+-------------+------------------------------+--------------------------------------------------+
| mat4 | `` omw.invProjectionMatrix `` | The inverse of the camera's projection matrix |
+-------------+------------------------------+--------------------------------------------------+
| mat4 | `` omw.viewMatrix `` | The camera's view matrix |
+-------------+------------------------------+--------------------------------------------------+
| mat4 | `` omw.prevViewMatrix `` | The camera's previous frame view matrix |
+-------------+------------------------------+--------------------------------------------------+
| mat4 | `` omw.invViewMatrix `` | The inverse of the camera's view matrix |
+-------------+------------------------------+--------------------------------------------------+
| vec4 | `` omw.eyePos `` | The camera's eye position |
+-------------+------------------------------+--------------------------------------------------+
| vec4 | `` omw.eyeVec `` | The normalized camera's eye vector |
+-------------+------------------------------+--------------------------------------------------+
| vec4 | `` omw.fogColor `` | The RGBA color of fog |
+-------------+------------------------------+--------------------------------------------------+
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| vec4 | `` omw.ambientColor `` | The RGBA color of scene ambient |
+-------------+------------------------------+--------------------------------------------------+
| vec4 | `` omw.skyColor `` | The RGBA color of sky |
+-------------+------------------------------+--------------------------------------------------+
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| vec4 | `` omw.sunColor `` | The RGBA color of sun |
+-------------+------------------------------+--------------------------------------------------+
| vec4 | `` omw.sunPos `` | The normalized sun direction |
| | | |
| | | When the sun is set `omw.sunpos.z`
+-------------+------------------------------+--------------------------------------------------+
| vec2 | `` omw.resolution `` | The render target's resolution |
+-------------+------------------------------+--------------------------------------------------+
| vec2 | `` omw.rcpResolution `` | Reciprocal of the render target resolution |
+-------------+------------------------------+--------------------------------------------------+
| vec2 | `` omw.fogNear `` | The units at which the fog begins to render |
+-------------+------------------------------+--------------------------------------------------+
| float | `` omw.fogFar `` | The units at which the fog ends |
+-------------+------------------------------+--------------------------------------------------+
| float | `` omw.near `` | The camera's near clip |
+-------------+------------------------------+--------------------------------------------------+
| float | `` omw.far `` | The camera's far clip |
+-------------+------------------------------+--------------------------------------------------+
| float | `` omw.gameHour `` | The game hour in range [0,24) |
+-------------+------------------------------+--------------------------------------------------+
| float | `` omw.sunVis `` | The sun's visibility between [0, 1] |
| | | |
| | | Influenced by types of weather |
| | | |
| | | Closer to zero during overcast weathers |
+-------------+------------------------------+--------------------------------------------------+
| float | `` omw.waterHeight `` | The water height of current cell |
| | | |
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| | | Exterior water level is always rendered at -1.0 |
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+-------------+------------------------------+--------------------------------------------------+
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| bool | `` omw.isWaterEnabled `` | True if water is enabled for current cell |
+-------------+------------------------------+--------------------------------------------------+
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| float | `` omw.simulationTime `` | The time in milliseconds since simulation began |
+-------------+------------------------------+--------------------------------------------------+
| float | `` omw.deltaSimulationTime `` | The change in `omw.simulationTime`
+-------------+------------------------------+--------------------------------------------------+
| float | `` omw.windSpeed `` | The current wind speed |
+-------------+------------------------------+--------------------------------------------------+
| float | `` omw.weatherTransition `` | The transition factor between weathers [0, 1] |
+-------------+------------------------------+--------------------------------------------------+
| int | `` omw.weatherID `` | The current weather ID |
+-------------+------------------------------+--------------------------------------------------+
| int | `` omw.nextWeatherID `` | The next weather ID |
+-------------+------------------------------+--------------------------------------------------+
| bool | `` omw.isUnderwater `` | True if player is submerged underwater |
+-------------+------------------------------+--------------------------------------------------+
| bool | `` omw.isInterior `` | True if player is in an interior |
| | | |
| | | False for interiors that behave like exteriors |
+-------------+------------------------------+--------------------------------------------------+
Builtin Macros
##############
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+-----------------------+----------------+----------------------------------------------------------------------+
| Macro | Definition | Description |
+=======================+================+======================================================================+
|`` OMW_REVERSE_Z `` | `` 0 `` or `` 1 `` | Whether a reversed depth buffer is in use. |
| | | |
| | | `` 0 `` Depth sampler will be in range [1, 0] |
| | | |
| | | `` 1 `` Depth sampler will be in range [0, 1] |
+-----------------------+----------------+----------------------------------------------------------------------+
|`` OMW_RADIAL_FOG `` | `` 0 `` or `` 1 `` | Whether radial fog is in use. |
| | | |
| | | `` 0 `` Fog is linear |
| | | |
| | | `` 1 `` Fog is radial |
+-----------------------+----------------+----------------------------------------------------------------------+
|`` OMW_EXPONENTIAL_FOG ` ` | ` ` 0 `` or `` 1 `` | Whether exponential fog is in use. |
| | | |
| | | `` 0 `` Fog is linear |
| | | |
| | | `` 1 `` Fog is exponential |
+-----------------------+----------------+----------------------------------------------------------------------+
| `` OMW_HDR `` | `` 0 `` or `` 1 `` | Whether average scene luminance is computed every frame. |
| | | |
| | | `` 0 `` Average scene luminance is not computed |
| | | |
| | | `` 1 `` Average scene luminance is computed |
+-----------------------+----------------+----------------------------------------------------------------------+
| `` OMW_NORMALS `` | `` 0 `` or `` 1 `` | Whether normals are available as a sampler in the technique. |
| | | |
| | | `` 0 `` Normals are not available |
| | | |
| | | `` 1 `` Normals are available. |
+-----------------------+----------------+----------------------------------------------------------------------+
| `` OMW_MULTIVIEW `` | `` 0 `` or `` 1 `` | Whether multiview rendering is in use. |
| | | |
| | | `` 0 `` Multiview not in use |
| | | |
| | | `` 1 `` Multiview in use. |
+-----------------------+----------------+----------------------------------------------------------------------+
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Builtin Functions
#################
The following functions can be accessed in any fragment or vertex shader.
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+--------------------------------------------------+-------------------------------------------------------------------------------+
| Function | Description |
+==================================================+===============================================================================+
| `` float omw_GetDepth(vec2) `` | Returns the depth value from a sampler given a uv coordinate. |
| | |
| | Reverses sampled value when `` OMW_REVERSE_Z `` is set. |
+--------------------------------------------------+-------------------------------------------------------------------------------+
| `` float omw_GetEyeAdaptation() `` | Returns the average scene luminance in range [0, 1]. |
| | |
| | If HDR is not in use, this returns `1.0`
| | |
| | Scene luminance is always calculated on original scene texture. |
+--------------------------------------------------+-------------------------------------------------------------------------------+
| `` vec4 omw_GetLastShader(vec2 uv) `` | Returns RGBA color output of the last shader |
+--------------------------------------------------+-------------------------------------------------------------------------------+
| `` vec4 omw_GetLastPass(vec2 uv) `` | Returns RGBA color output of the last pass |
+--------------------------------------------------+-------------------------------------------------------------------------------+
| `` vec3 omw_GetNormals(vec2 uv) `` | Returns normalized worldspace normals [-1, 1] |
| | |
| | The values in sampler are in [0, 1] but are transformed to [-1, 1] |
+--------------------------------------------------+-----------------------+-------------------------------------------------------+
| `` vec3 omw_GetWorldPosFromUV(vec2 uv) `` | Returns world position for given uv coordinate. |
+--------------------------------------------------+-----------------------+-------------------------------------------------------+
| `` float omw_GetLinearDepth(vec2 uv) `` | Returns the depth in game units for given uv coordinate. |
+--------------------------------------------------+-----------------------+-------------------------------------------------------+
| `` float omw_EstimateFogCoverageFromUV(vec2 uv) `` | Returns a fog coverage in the range from 0.0 (no fog) and 1.0 (full fog) |
| | |
| | Calculates an estimated fog coverage for given uv coordinate. |
+--------------------------------------------------+-----------------------+-------------------------------------------------------+
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Special Attributes
##################
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To maintain maximum compatibility with future releases, OpenMW defines specific keywords, attributes, and functions for you to use. These should be used instead of their
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GLSL equivalent. Refer to the table below to view these mappings.
+-------------------+---------------------------------------------------------+
| .omwfx | Description |
+===================+=========================================================+
| omw_In | use in place of `` in `` and `` varying `` |
+-------------------+---------------------------------------------------------+
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| omw_Out | use in place of `` out `` and `` varying `` |
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+-------------------+---------------------------------------------------------+
| omw_Position | use in place of `` gl_Position `` |
+-------------------+---------------------------------------------------------+
| omw_Vertex | use in place of `` gl_Vertex `` |
+-------------------+---------------------------------------------------------+
| omw_Fragment | use in place of `` gl_FragData[*] `` and `` gl_FragColor ` ` |
+-------------------+---------------------------------------------------------+
| omw_Texture1D() | use in place of `` texture1D() `` or `` texture() `` |
+-------------------+---------------------------------------------------------+
| omw_Texture2D() | use in place of `` texture2D() `` or `` texture() `` |
+-------------------+---------------------------------------------------------+
| omw_Texture3D() | use in place of `` texture3D() `` or `` texture() `` |
+-------------------+---------------------------------------------------------+
Blocks
######
`` fragment ``
***** ***** ***
Declare your passes with `` fragment `` followed by a unique name. We will define the order of these passes later on.
Each `` fragment `` block must contain valid GLSL. Below is a simple example of defining two passes.
.. code-block :: none
fragment pass {
void main()
{
omw_FragColor = vec4(1.0);
}
}
fragment otherPass {
omw_In vec2 omw_TexCoord;
void main()
{
omw_FragColor = omw_GetLastPass(omw_TexCoord);
}
}
`` vertex ``
***** ***** *
For every `` fragment `` block you declare, OpenMW generates a default vertex shader if you do not define one. This is used to draw the fullscreen triangle used in postprocessing.
This means you rarely need to use a custom vertex shader. Using a vertex shader can sometimes be useful when you need to do lots of complicated calculations that don't rely on pixel location.
The vertex shader only invocates on the `3`
Below is an example of passing a value through a custom vertex shader to the fragment shader.
.. code-block :: none
vertex pass {
#if OMW_USE_BINDINGS
omw_In vec2 omw_Vertex;
#endif
uniform sampler2D noiseSampler;
omw_Out vec2 omw_TexCoord;
// custom output from vertex shader
omw_Out float noise;
void main()
{
omw_Position = vec4(omw_Vertex.xy, 0.0, 1.0);
omw_TexCoord = omw_Position.xy * 0.5 + 0.5;
noise = sqrt(omw_Texture2D(noiseSampler, vec2(0.5, 0.5)).r);
}
}
fragment pass {
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omw_In vec2 omw_TexCoord;
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// our custom output from the vertex shader is available
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omw_In float noise;
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void main()
{
omw_FragColor = vec4(1.0);
}
}
`` technique ``
***** ***** ***
Exactly one `` technique `` block is required for every shader file. In this we define important traits like author, description, requirements, and flags.
+------------------+--------------------+---------------------------------------------------+
| Property | Type | Description |
+==================+====================+===================================================+
| passes | literal list | `` , `` separated list of pass names |
+------------------+--------------------+---------------------------------------------------+
| version | string | Shader version that shows in HUD |
+------------------+--------------------+---------------------------------------------------+
| description | string | Shader description that shows in HUD |
+------------------+--------------------+---------------------------------------------------+
| author | string | Shader authors that shows in HUD |
+------------------+--------------------+---------------------------------------------------+
| glsl_Version | integer | GLSL version |
+------------------+--------------------+---------------------------------------------------+
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| glsl_profile | string | GLSL profile, like `` compatibility `` |
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+------------------+--------------------+---------------------------------------------------+
| glsl_extensions | literal list | `` , `` separated list of required GLSL extensions |
+------------------+--------------------+---------------------------------------------------+
| hdr | boolean | Whether HDR eye adaptation is required. |
+------------------+--------------------+---------------------------------------------------+
| pass_normals | boolean | Pass normals from the forward passes. |
| | | |
| | | If unsupported, `OMW_NORMALS` `0`
+------------------+--------------------+---------------------------------------------------+
| flags | `SHADER_FLAG`_ | `` , `` separated list of shader flags |
+------------------+--------------------+---------------------------------------------------+
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| dynamic | boolean | Whether shader is exposed to Lua |
+------------------+--------------------+---------------------------------------------------+
When `` dynamic `` is set to `` true `` , the shaders order cannot be manually moved, enabled, or disabled. The shaders state
can only be controlled via a Lua script.
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In the code snippet below, a shader is defined that requires GLSL `330`
.. code-block :: none
fragment dummy {
void main()
{
omw_FragColor = vec4(0.0);
}
}
technique {
passes = dummy;
glsl_version = 330;
hdr = true;
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flags = disable_interiors, disable_abovewater;
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}
`` sampler_* ``
***** ***** ***
Any texture in the VFS can be loaded by a shader. All passes within the technique will have access to this texture as a sampler.
OpenMW currently supports `` 1D `` , `` 2D `` , and `` 3D `` texture samplers, cubemaps can not yet be loaded.
+-------------+
| Block |
+=============+
| sampler_1d |
+-------------+
| sampler_2d |
+-------------+
| sampler_3d |
+-------------+
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.. warning ::
OpenMW vertically flips all DDS textures when loading them, with the exception of `` 3D `` textures.
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The properties for a `` sampler_* `` block are as following.
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The only required property for a texture is its `` source `` .
+-----------------------+-----------------------+
| Property | Type |
+=======================+=======================+
|`` source `` | string |
+-----------------------+-----------------------+
|`` min_filter `` | `FILTER_MODE`_ |
+-----------------------+-----------------------+
|`` mag_filter `` | `FILTER_MODE`_ |
+-----------------------+-----------------------+
|`` wrap_s `` | `WRAP_MODE`_ |
+-----------------------+-----------------------+
|`` wrap_t `` | `WRAP_MODE`_ |
+-----------------------+-----------------------+
|`` wrap_r `` | `WRAP_MODE`_ |
+-----------------------+-----------------------+
|`` compression `` | `COMPRESSION_MODE`_ |
+-----------------------+-----------------------+
|`` source_format `` | `SOURCE_FORMAT`_ |
+-----------------------+-----------------------+
|`` source_type `` | `SOURCE_TYPE`_ |
+-----------------------+-----------------------+
|`` internal_format `` | `INTERNAL_FORMAT`_ |
+-----------------------+-----------------------+
In the code snippet below, a simple noise texture is loaded with nearest filtering.
.. code-block :: none
sampler_2d noise {
source = "textures/noise.png";
mag_filter = nearest;
min_filter = nearest;
}
To use the sampler, define the appropriately named `sampler2D`
.. code-block :: none
fragment pass {
omw_In vec2 omw_TexCoord;
uniform sampler2D noise;
void main()
{
// ...
vec4 noise = omw_Texture2D(noise, omw_TexCoord);
}
}
`` uniform_* ``
***** ***** *** *
It is possible to define settings for your shaders that can be adjusted by either users or a Lua script.
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+-----------------+----------+----------+----------+---------+----------+--------------+-------------------+---------+
| Block | default | min | max | static | step | description | display_name | header |
+=================+==========+==========+==========+=========+==========+==============+===================+=========+
|`` uniform_bool `` | boolean | x | x | boolean | x | string | string | string |
+-----------------+----------+----------+----------+---------+----------+--------------+-------------------+---------+
|`` uniform_float ` ` | float | float | float | boolean | float | string | string | string |
+-----------------+----------+----------+----------+---------+----------+--------------+-------------------+---------+
|`` uniform_int `` | integer | integer | integer | boolean | integer | string | string | string |
+-----------------+----------+----------+----------+---------+----------+--------------+-------------------+---------+
|`` uniform_vec2 `` | vec2 | vec2 | vec2 | boolean | vec2 | string | string | string |
+-----------------+----------+----------+----------+---------+----------+--------------+-------------------+---------+
|`` uniform_vec3 `` | vec3 | vec3 | vec3 | boolean | vec3 | string | string | string |
+-----------------+----------+----------+----------+---------+----------+--------------+-------------------+---------+
|`` uniform_vec4 `` | vec4 | vec4 | vec4 | boolean | vec4 | string | string | string |
+-----------------+----------+----------+----------+---------+----------+--------------+-------------------+---------+
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The `` description `` field is used to display a toolip when viewed in the in-game HUD. The `` header `` field
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field can be used to organize uniforms into groups in the HUD. The `` display_name `` field can be used to create a
more user friendly uniform name for display in the HUD.
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If you would like a uniform to be adjustable with Lua API you `must` `` static = false; `` . Doing this
will also remove the uniform from the players HUD.
Below is an example of declaring a `` vec3 `` uniform.
.. code-block :: none
uniform_vec3 uColor {
default = vec3(0,1,1);
min = vec3(0,0,0);
max = vec3(1,1,1);
step = vec3(0.1, 0.1, 0.1);
description = "Color uniform";
static = true;
header = "Colors";
}
To use the uniform you can reference it in any pass, it should **not** be declared with the `` uniform `` keyword.
.. code-block :: none
fragment pass {
void main()
{
// ...
vec3 color = uColor;
}
}
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You can use uniform arrays as well, but they are restricted to the `Lua API <../lua-scripting/openmw_postprocessing.html> `_ scripts.
These uniform blocks must be defined with the new `` size `` parameter.
.. code-block :: none
uniform_vec3 uArray {
size = 10;
}
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`` render_target ``
***** ***** ***** **
Normally when defining passes, OpenMW will take care of setting up all of the render targets. Sometimes, this behavior
is not wanted and you want a custom render target.
+------------------+---------------------+-----------------------------------------------------------------------------+
| Property | Type | Description |
+==================+=====================+=============================================================================+
| min_filter | `FILTER_MODE`_ | x |
+------------------+---------------------+-----------------------------------------------------------------------------+
| mag_filter | `FILTER_MODE`_ | x |
+------------------+---------------------+-----------------------------------------------------------------------------+
| wrap_s | `WRAP_MODE`_ | x |
+------------------+---------------------+-----------------------------------------------------------------------------+
| wrap_t | `WRAP_MODE`_ | x |
+------------------+---------------------+-----------------------------------------------------------------------------+
| internal_format | `INTERNAL_FORMAT`_ | x |
+------------------+---------------------+-----------------------------------------------------------------------------+
| source_type | `SOURCE_TYPE`_ | x |
+------------------+---------------------+-----------------------------------------------------------------------------+
| source_format | `SOURCE_FORMAT`_ | x |
+------------------+---------------------+-----------------------------------------------------------------------------+
| width_ratio | float | Automatic width as a percentage of screen width |
+------------------+---------------------+-----------------------------------------------------------------------------+
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| height_ratio | float | Automatic height as a percentage of screen height |
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+------------------+---------------------+-----------------------------------------------------------------------------+
| width | float | Width in pixels |
+------------------+---------------------+-----------------------------------------------------------------------------+
| height | float | Height in pixels |
+------------------+---------------------+-----------------------------------------------------------------------------+
| mipmaps | boolean | Whether mipmaps should be generated every frame |
+------------------+---------------------+-----------------------------------------------------------------------------+
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To use the render target a pass must be assigned to it, along with any optional clear or blend modes.
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In the code snippet below a rendertarget is used to draw the red channel of a scene at half resolution, then a quarter. As a restriction,
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only three render targets can be bound per pass with `` rt1 `` , `` rt2 `` , `` rt3 `` , respectively.
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.. code-block :: none
render_target RT_Downsample {
width_ratio = 0.5;
height_ratio = 0.5;
internal_format = r16f;
source_type = float;
source_format = red;
}
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render_target RT_Downsample4 {
width_ratio = 0.25;
height_ratio = 0.25;
}
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fragment downsample2x(target=RT_Downsample) {
omw_In vec2 omw_TexCoord;
void main()
{
omw_FragColor.r = omw_GetLastShader(omw_TexCoord).r;
}
}
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fragment downsample4x(target=RT_Downsample4, rt1=RT_Downsample) {
omw_In vec2 omw_TexCoord;
void main()
{
omw_FragColor = omw_Texture2D(RT_Downsample, omw_TexCoord);
}
}
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Now, when the `downsample2x`
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one assigned by the engine.
Simple Example
##############
Let us go through a simple example in which we apply a simple desaturation
filter with a user-configurable factor.
Our first step is defining our user-configurable variable. In this case all we
want is a normalized value between 0 and 1 to influence the amount of
desaturation to apply to the scene. Here we setup a new variable of type
`` float `` , define a few basic properties, and give it a tooltip description.
.. code-block :: none
uniform_float uDesaturationFactor {
default = 0.5;
min = 0.0;
max = 1.0;
step = 0.05;
static = true;
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display_name = "Desaturation Factor";
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description = "Desaturation factor. A value of 1.0 is full grayscale.";
}
Now, we can setup our first pass. Remember a pass is just a pixel shader invocation.
.. code-block :: none
fragment desaturate {
omw_In vec2 omw_TexCoord;
void main()
{
// fetch scene texture from last shader
vec4 scene = omw_GetLastShader(omw_TexCoord);
// desaturate RGB component
const vec3 luminance = vec3(0.299, 0.587, 0.144);
float gray = dot(luminance, scene.rgb);
omw_FragColor = vec4(mix(scene.rgb, vec3(gray), uDesaturationFactor), scene.a);
}
}
Next we can define our `` technique `` block, which is in charge of glueing
together passes, setting up metadata, and setting up various flags.
.. code-block :: none
technique {
description = "Desaturates scene";
passes = desaturate;
version = "1.0";
author = "Fargoth";
passes = desaturate;
}
Putting it all together we have this simple shader.
.. code-block :: none
uniform_float uDesaturationFactor {
default = 0.5;
min = 0.0;
max = 1.0;
step = 0.05;
description = "Desaturation factor. A value of 1.0 is full grayscale.";
}
fragment desaturate {
omw_In vec2 omw_TexCoord;
void main()
{
// fetch scene texture from last shader
vec4 scene = omw_GetLastShader(omw_TexCoord);
// desaturate RGB component
const vec3 luminance = vec3(0.299, 0.587, 0.144);
float gray = dot(luminance, scene.rgb);
omw_FragColor = vec4(mix(scene.rgb, vec3(gray), uDesaturationFactor), scene.a);
}
}
technique {
description = "Desaturates scene";
passes = desaturate;
version = "1.0";
author = "Fargoth";
passes = desaturate;
}
Types
#####
`SHADER_FLAG`
***** ***** ***
+--------------------+--------------------------------------------------------------------------+
| Flag | Description |
+====================+==========================================================================+
| disable_interiors | Disable in interiors. |
+--------------------+--------------------------------------------------------------------------+
| disable_exteriors | Disable when in exteriors or interiors which behave like exteriors. |
+--------------------+--------------------------------------------------------------------------+
| disable_underwater | Disable when underwater. |
+--------------------+--------------------------------------------------------------------------+
| disable_abovewater | Disable when above water. |
+--------------------+--------------------------------------------------------------------------+
| disable_sunglare | Disables builtin sunglare. |
+--------------------+--------------------------------------------------------------------------+
| hidden | Shader does not show in the HUD. Useful for shaders driven by Lua API. |
+--------------------+--------------------------------------------------------------------------+
`BLEND_EQ`
***** *****
+-------------------+---------------------------+
| .omwfx | OpenGL |
+===================+===========================+
| rgba_min | GL_MIN |
+-------------------+---------------------------+
| rgba_max | GL_MAX |
+-------------------+---------------------------+
| alpha_min | GL_ALPHA_MIN_SGIX |
+-------------------+---------------------------+
| alpha_max | GL_ALPHA_MAX_SGIX |
+-------------------+---------------------------+
| logic_op | GL_LOGIC_OP |
+-------------------+---------------------------+
| add | GL_FUNC_ADD |
+-------------------+---------------------------+
| subtract | GL_FUNC_SUBTRACT |
+-------------------+---------------------------+
| reverse_subtract | GL_FUNC_REVERSE_SUBTRACT |
+-------------------+---------------------------+
`BLEND_FUNC`
***** ***** **
+---------------------------+------------------------------+
| .omwfx | OpenGL |
+===========================+==============================+
| dst_alpha | GL_DST_ALPHA |
+---------------------------+------------------------------+
| dst_color | GL_DST_COLOR |
+---------------------------+------------------------------+
| one | GL_ONE |
+---------------------------+------------------------------+
| one_minus_dst_alpha | GL_ONE_MINUS_DST_ALPHA |
+---------------------------+------------------------------+
| one_minus_dst_color | GL_ONE_MINUS_DST_COLOR |
+---------------------------+------------------------------+
| one_minus_src_alpha | GL_ONE_MINUS_SRC_ALPHA |
+---------------------------+------------------------------+
| one_minus_src_color | GL_ONE_MINUS_SRC_COLOR |
+---------------------------+------------------------------+
| src_alpha | GL_SRC_ALPHA |
+---------------------------+------------------------------+
| src_alpha_saturate | GL_SRC_ALPHA_SATURATE |
+---------------------------+------------------------------+
| src_color | GL_SRC_COLOR |
+---------------------------+------------------------------+
| constant_color | GL_CONSTANT_COLOR |
+---------------------------+------------------------------+
| one_minus_constant_color | GL_ONE_MINUS_CONSTANT_COLOR |
+---------------------------+------------------------------+
| constant_alpha | GL_CONSTANT_ALPHA |
+---------------------------+------------------------------+
| one_minus_constant_alpha | GL_ONE_MINUS_CONSTANT_ALPHA |
+---------------------------+------------------------------+
| zero | GL_ZERO |
+---------------------------+------------------------------+
`INTERNAL_FORMAT`
***** ***** ***** **
+--------------------+-----------------------+
| .omwfx | OpenGL |
+====================+=======================+
| red | GL_RED |
+--------------------+-----------------------+
| r16f | GL_R16F |
+--------------------+-----------------------+
| r32f | GL_R32F |
+--------------------+-----------------------+
| rg | GL_RG |
+--------------------+-----------------------+
| rg16f | GL_RG16F |
+--------------------+-----------------------+
| rg32f | GL_RG32F |
+--------------------+-----------------------+
| rgb | GL_RGB |
+--------------------+-----------------------+
| rgb16f | GL_RGB16F |
+--------------------+-----------------------+
| rgb32f | GL_RGB32F |
+--------------------+-----------------------+
| rgba | GL_RGBA |
+--------------------+-----------------------+
| rgba16f | GL_RGBA16F |
+--------------------+-----------------------+
| rgba32f | GL_RGBA32F |
+--------------------+-----------------------+
| depth_component16 | GL_DEPTH_COMPONENT16 |
+--------------------+-----------------------+
| depth_component24 | GL_DEPTH_COMPONENT24 |
+--------------------+-----------------------+
| depth_component32 | GL_DEPTH_COMPONENT32 |
+--------------------+-----------------------+
| depth_component32f | GL_DEPTH_COMPONENT32F |
+--------------------+-----------------------+
`SOURCE_TYPE`
***** ***** ***
+--------------------+-----------------------+
| .omwfx | OpenGL |
+====================+=======================+
| byte | GL_BYTE |
+--------------------+-----------------------+
| unsigned_byte | GL_UNSIGNED_BYTE |
+--------------------+-----------------------+
| short | GL_SHORT |
+--------------------+-----------------------+
| unsigned_short | GL_UNSIGNED_SHORT |
+--------------------+-----------------------+
| int | GL_INT |
+--------------------+-----------------------+
| unsigned_int | GL_UNSIGNED_INT |
+--------------------+-----------------------+
| unsigned_int_24_8 | GL_UNSIGNED_INT_24_8 |
+--------------------+-----------------------+
| float | GL_FLOAT |
+--------------------+-----------------------+
| double | GL_DOUBLE |
+--------------------+-----------------------+
`SOURCE_FORMAT`
***** ***** *****
+---------+---------+
| .omwfx | OpenGL |
+=========+=========+
| red | GL_RED |
+---------+---------+
| rg | GL_RG |
+---------+---------+
| rgb | GL_RGB |
+---------+---------+
| bgr | GL_BGR |
+---------+---------+
| rgba | GL_RGBA |
+---------+---------+
| bgra | GL_BGRA |
+---------+---------+
`FILTER_MODE`
***** ***** ***
+-------------------------+----------------------------+
| .omwfx | OpenGL |
+=========================+============================+
| linear | GL_LINEAR |
+-------------------------+----------------------------+
| linear_mipmap_linear | GL_LINEAR_MIPMAP_LINEAR |
+-------------------------+----------------------------+
| linear_mipmap_nearest | GL_LINEAR_MIPMAP_NEAREST |
+-------------------------+----------------------------+
| nearest | GL_NEAREST |
+-------------------------+----------------------------+
| nearest_mipmap_linear | GL_NEAREST_MIPMAP_LINEAR |
+-------------------------+----------------------------+
| nearest_mipmap_nearest | GL_NEAREST_MIPMAP_NEAREST |
+-------------------------+----------------------------+
`WRAP_MODE`
***** ***** *
+------------------+---------------------+
| .omwfx | OpenGL |
+==================+=====================+
| clamp_to_edge | GL_CLAMP_TO_EDGE |
+------------------+---------------------+
| clamp_to_border | GL_CLAMP_TO_BORDER |
+------------------+---------------------+
| repeat | GL_REPEAT |
+------------------+---------------------+
| mirror | GL_MIRRORED_REPEAT |
+------------------+---------------------+
`COMPRESSION_MODE`
***** ***** ***** ***
+-------------+
| .omwfx |
+=============+
| auto |
+-------------+
| arb |
+-------------+
| s3tc_dxt1 |
+-------------+
| s3tc_dxt3 |
+-------------+
| s3tc_dxt5 |
+-------------+
| pvrtc_2bpp |
+-------------+
| pvrtc_4bpp |
+-------------+
| etc |
+-------------+
| etc2 |
+-------------+
| rgtc1 |
+-------------+
| rgtc2 |
+-------------+
| s3tc_dxt1c |
+-------------+
| s3tc_dxt1a |
+-------------+
