Creating a Waterfall Material

This is a Tutorial to create a Waterfallmaterial.

The Normalmap

For a waterfall you need a Normalmap which Refracts the light so that the things behind it gets distorted.
I used The_GIMP with a normalmap plug-in for this Tutorial.
Make a new Image with a maximum size of 1024x1024, I used a size of 512x512 pixels. We create now a solid Noise so you go to Filters → Render → Clouds → Solid noise
you have to set the x value to 16.0(the highest possible) the y value between 1.0 and 3.0
the Detail to 15(highest possible) and you must check the Tileable box to make it seamless.
Now it should look similar to Pic1.

Pic1

Save your file as TGA and open it with VTFEdit.
A dialog will open like in Pic2.
You have to check the Generate Normal map box and set the Filter to 4 Sample,
the Height Source to Average RGB and the Scale to 9.0 like in the Pic2. You can set Normal Format and Alpha Format to RGBA8888.

Pic2

After you converted it to a Normalmap it should look like Pic3.
Save the Normalmap now in a folder like "nature/" in your mod materials folder or game materials folder and give it a name like "waterfall_n.vtf".

Pic3

The Material

The basic Material

At first you have create a materialfile(vmt) and name it waterfall.vmt or similar. In the materialfile you should use the LightmappedReflective shader:

"LightmappedReflective"
{
}

So we don't need a $basetexture but we need a $RefractTexture and optionaly a $ReflectTexture.
The attribute for the $RefractTexture parameter is _rt_WaterRefraction and for $ReflectTexture is it _rt_WaterReflection.
Now it should look like this:

"LightmappedReflective"
{
	"$RefractTexture" _rt_WaterRefraction
}

That is now the base of our Material.
Now we add the Normalmap with $normalmap and the path to it like "nature/waterfall_n".
For the right refraction amount we add $refractamount with a value between 0 and 1 like 0.08.
Now your vmt should look like this:

"LightmappedReflective"
{
	"$RefractTexture" _rt_WaterRefraction
	"$normalmap" "nature/waterfall_n"
 	"$refractamount" .08
}

$Surfaceprop

You should add "$surfaceprop" "Water" for correct effects and physics.

Scroll animation

When you use your material in a map you should see that the refraction looks frozen, so you must add a "Scrolling" effect.
We can do this with an animated texture or the easier way we add "Proxies" like this

"Proxies"
{
	"TextureScroll"
	{
	}
}

For the TextureScroll Proxy we need "texturescrollvar", "texturescrollrate" and "texturescrollangle".
With "texturescrollvar" we specify the target like we need "$bumpTransform".
With "texturescrollrate" we specify the scrolling speed you have to test yourself which value could be the best, I used 1.3.
With "texturescrollangle" we specify the moving direction in degrees we use 270 degrees for it, for a down flowing.
So now the whole vmt should look like this

"LightmappedReflective"
{
	"$RefractTexture" _rt_WaterRefraction
	"$normalmap" "nature/waterfall_n"
	"$refractamount" .08
	"Proxies"
	{
		"TextureScroll"
		{
			"texturescrollvar" "$bumpTransform"
			"texturescrollrate" 1.3
			"texturescrollangle" 270.00
		}
	}
}

Optional: Reflection

When you want Reflections you must add $ReflectTexture, $reflectamount and $fresnelpower. Use for $fresnelpower a value of 5 because I think it looks the best. For $reflectamount you must find your own value because there is no "Perfect value".

"LightmappedReflective"
{
	"$RefractTexture" _rt_WaterRefraction
	"$ReflectTexture" _rt_WaterReflection
 	"$normalmap" "nature/waterfall_n"
 	"$refractamount" .08
 	"$reflectamount" .3
	"$fresnelpower" 5
 	"Proxies"
	{
		"TextureScroll"
		{
			"texturescrollvar" "$bumpTransform"
			"texturescrollrate" 1.3
			"texturescrollangle" 270.00
		}
	}
}

TODO

• embeding into a map