View source for Liquid materials

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{{LanguageBar|title = Water (shader)}}
[[Water]] does not ''need'' to use the {{mono|Water}} shader! If a less realistic effect is desired, or the water volume is oddly shaped, other shaders can be used, such as [[LightmappedGeneric]] or [[Refract]]. The method for creating the materials is the same. Liquids using using any shader other than Water will always be considered cheap.

== Parameters ==

{{MatParam|%CompileWater|bool|This is needed to make a map using the material compile properly.}}
{{MatParam|%CompileSlime|bool|Can be used instead of %CompileWater to get different particles. Planar reflections don't work with this, due to not applying [[Surface flag|SURF_WARP]].}}

{{MatParam|$abovewater|bool|Whether this material is used for above or below the water’s surface.<br>
{{note|Not setting this in the VMT will automatically force it to 1. If not defined, a warning will appear saying <code>Need to set $abovewater for material x</code>}}}}
{{MatParam|$bottommaterial|material|Required parameter. This is the material ('''not''' texture) to use when underneath the water’s surface. The bottom material must have <code>$reflecttexture</code>, <code>$abovewater</code> and <code>$envmap</code> disabled, but can otherwise do whatever it wants. {{tip|Add {{cmd|%notooltexture}} to the bottom material to hide it in the texture browser {{hammer++|not}}.}} }}
{{note|If the above water material does not have reflections, refractions, or $underwateroverlay: $abovewater can be omitted, [[$nocull]] can be used, and $bottommaterial can be set to the same material as the abovewater material.}}
{{MatParam|$underwateroverlay|material|Applies a refracting screen overlay when the camera is underwater. Generally used with <code>effects\water_warp01</code>. Requires <code>$abovewater</code> to be 0.<br>
{{note|This is technically not a parameter on the water shader, meaning it can be abused for other unintended purposes! The overlay may still be applied even when the underwater material is told not to render ( {{ent|$no_draw}})}}|since={{src07}}}}

=== Fog ===

{{MatParam|$fogenable|bool|Enable volumetric fog for the water. Note that the [[Water (Shader)|Water]] shader will always have fog regardless of this parameter, but $fogstart and $fogend will not work without it. Optional for all other shaders.}}
{{MatParam|$fogcolor|RGB matrix|Color of the water’s volumetric fog. Generally this value should match the color used in the bottom material.<br>
{{Important| If this parameter is not defined in a VMT, the shader will force its value to <code>"[1 0 0]"</code> and spew an error message saying <code>Material x needs to have a $fogcolor.</code>}}
{{warning|
Cheap water treats this parameters as a linear value where 0.0 is 0% and 1.0 is 100%.<br>
Expensive water treats this parameter as a Gamma value,<br>
and due do this, each component ( red, green and blue respectively ) can not go above 1.0 or below 0.0 ( on expensive water )<br>
To calculate the eventual linear value that the shader is supplied with, apply the formula <code>x^(1/2.2)</code>{{tip|While expensive water cannot, cheap water ''can'' go higher than 1.0, achieving a more "neon" effect.}} }}}}

{{MatParam|$fogstart|float|Distance in units/inches from the eye at which water fog starts.
: {{warning|Must be 0 for edge fading to work properly.}}}}
{{MatParam|$fogend|float|Distance in units/inches from the eye at which water fog ends.}}

=== Other ===
{{MatParam|$surfaceprop|water|Tells the physics system that the surface is water. See [[$surfaceprop]].}}
{{MatParam|%tooltexture|texture|Defines the texture Hammer will display in the material browser. Any texture can be used, but it is customary to use the [[$normalmap]].}}
; <code>WaterLOD proxy</code>
: This connects the [[water_lod_control]] entity in a level to the water’s internal parameters. This must be declared in the material for the LOD mechanisms to work properly.

[[Category:Water]]