<?xml version="1.0" encoding="utf-8"?>
<!-- Transition effect  starting from the base texture of the scenery, and changing textures according to slope in one or two steps.

parameters :
    texture[0] -> base texture from the scenery
    texture[2] -> intermediate texture if transitions is set to 2
    texture[3] -> texture you want to transition to
    texture[4] -> snow texture you want applied above snow-limit (I recommend using the corespondent winter texture for the base texture that you can find in terrain.winter)

   transitions -> transitions number can be set to 1 or 2 (if set to 2 will allow for an intermediate step)
       inverse -> if this is se to 1 will keep the base texture on steep slopes and transition to the texture you want (useful to add some grass patches in rocky areas)
-->

<PropertyList>
    <name>Effects/transition</name>
    <inherits-from>Effects/terrain-default</inherits-from>
    <parameters>
	<texture n="2">
	    <image>Textures.high/Terrain/transition1.dds</image>
	    <filter>linear-mipmap-linear</filter>
	    <wrap-s>repeat</wrap-s>
	    <wrap-t>repeat</wrap-t>
	    <internal-format>normalized</internal-format>
	</texture>
	<texture n="3">
	    <image>Textures.high/Terrain/transition2.dds</image>
	    <filter>linear-mipmap-linear</filter>
	    <wrap-s>repeat</wrap-s>
	    <wrap-t>repeat</wrap-t>
	    <internal-format>normalized</internal-format>
	</texture>
	<texture n="4">
	    <image>Textures.high/Terrain/snow3.dds</image>
	    <filter>linear-mipmap-linear</filter>
	    <wrap-s>repeat</wrap-s>
	    <wrap-t>repeat</wrap-t>
	    <internal-format>normalized</internal-format>
	</texture>

	<rain-norm>
	    <use>/environment/rain-norm</use>
	</rain-norm>
	<snow-level>
	    <use>/sim/rendering/snow-level-m</use>
	</snow-level>

	<cloud-cover0>
	    <use>/environment/clouds/layer[0]/coverage-type</use>
	</cloud-cover0>
	<cloud-cover1>
	    <use>/environment/clouds/layer[1]/coverage-type</use>
	</cloud-cover1>
	<cloud-cover2>
	    <use>/environment/clouds/layer[2]/coverage-type</use>
	</cloud-cover2>
	<cloud-cover3>
	    <use>/environment/clouds/layer[3]/coverage-type</use>
	</cloud-cover3>
	<cloud-cover4>
	    <use>/environment/clouds/layer[4]/coverage-type</use>
	</cloud-cover4>

	<transitions type="float">2.0</transitions>
	<inverse type="float">0.0</inverse>
    </parameters>

    <!--<generate>
	<tangent type="int">6</tangent>
	<binormal type="int">7</binormal>
    </generate>-->

    <technique n="9">
	<predicate>
	    <and>
		<property>/sim/rendering/transition-shader</property>
		<property>/sim/rendering/shader-effects</property>
		<or>
		    <less-equal>
			<value type="float">2.0</value>
			<glversion/>
		    </less-equal>
		    <and>
			<extension-supported>GL_ARB_shader_objects</extension-supported>
			<extension-supported>GL_ARB_shading_language_100</extension-supported>
			<extension-supported>GL_ARB_vertex_shader</extension-supported>
			<extension-supported>GL_ARB_fragment_shader</extension-supported>
		    </and>
		</or>
	    </and>
	</predicate>

	<pass>
	    <lighting>true</lighting>
	    <!-- Use material values that are either inherited from the
	    terrain-default effect or supplied by an effect derived
	    from this one e.g., one created in the materials library. -->
	    <material>
		<ambient>
		    <use>material/ambient</use>
		</ambient>
		<diffuse>
		    <use>material/diffuse</use>
		</diffuse>
		<specular>
		    <use>material/specular</use>
		</specular>
		<color-mode>ambient-and-diffuse</color-mode>
	    </material>

	    <blend>
		<use>transparent</use>
	    </blend>

	    <alpha-test>
		<use>transparent</use>
	    </alpha-test>

	    <shade-model>smooth</shade-model>
	    <cull-face>back</cull-face>

	    <render-bin>
		<bin-number>
		    <use>render-bin/bin-number</use>
		</bin-number>
		<bin-name>
		    <use>render-bin/bin-name</use>
		</bin-name>
	    </render-bin>

	    <texture-unit>
		<unit>0</unit>
		<image>
		    <use>texture[0]/image</use>
		</image>
		<filter>
		    <use>texture[0]/filter</use>
		</filter>
		<wrap-s>
		    <use>texture[0]/wrap-s</use>
		</wrap-s>
		<wrap-t>
		    <use>texture[0]/wrap-t</use>
		</wrap-t>
		<internal-format>
		    <use>texture[0]/internal-format</use>
		</internal-format>
	    </texture-unit>

	    <texture-unit>
		<unit>1</unit>
		<image>
		    <use>texture[2]/image</use>
		</image>
		<filter>
		    <use>texture[2]/filter</use>
		</filter>
		<wrap-s>
		    <use>texture[2]/wrap-s</use>
		</wrap-s>
		<wrap-t>
		    <use>texture[2]/wrap-t</use>
		</wrap-t>
		<internal-format>
		    <use>texture[2]/internal-format</use>
		</internal-format>
	    </texture-unit>

	    <texture-unit>
		<unit>2</unit>
		<image>
		    <use>texture[3]/image</use>
		</image>
		<filter>
		    <use>texture[3]/filter</use>
		</filter>
		<wrap-s>
		    <use>texture[3]/wrap-s</use>
		</wrap-s>
		<wrap-t>
		    <use>texture[3]/wrap-t</use>
		</wrap-t>
		<internal-format>
		    <use>texture[3]/internal-format</use>
		</internal-format>
	    </texture-unit>

	    <texture-unit>
		<unit>3</unit>
		<image>
		    <use>texture[4]/image</use>
		</image>
		<filter>
		    <use>texture[4]/filter</use>
		</filter>
		<wrap-s>
		    <use>texture[4]/wrap-s</use>
		</wrap-s>
		<wrap-t>
		    <use>texture[4]/wrap-t</use>
		</wrap-t>
		<internal-format>
		    <use>texture[4]/internal-format</use>
		</internal-format>
	    </texture-unit>

	    <texture-unit>
		<unit>4</unit>
		<type>noise</type>
	    </texture-unit>

	    <program>
		<vertex-shader>Shaders/transition.vert</vertex-shader>
		<fragment-shader>Shaders/transition.frag</fragment-shader>
	    </program>

	    <uniform>
		<name>BaseTex</name>
		<type>sampler-2d</type>
		<value type="int">0</value>
	    </uniform>

	    <uniform>
		<name>SecondTex</name>
		<type>sampler-2d</type>
		<value type="int">1</value>
	    </uniform>

	    <uniform>
		<name>ThirdTex</name>
		<type>sampler-2d</type>
		<value type="int">2</value>
	    </uniform>

	    <uniform>
		<name>SnowTex</name>
		<type>sampler-2d</type>
		<value type="int">3</value>
	    </uniform>

	    <uniform>
		<name>NoiseTex</name>
		<type>sampler-3d</type>
		<value type="int">4</value>
	    </uniform>

	    <uniform>
		<name>RainNorm</name>
		<type>float</type>
		<value>
		    <use>rain-norm</use>
		</value>
	    </uniform>

	    <uniform>
		<name>SnowLevel</name>
		<type>float</type>
		<value>
		    <use>snow-level</use>
		</value>
	    </uniform>

	    <uniform>
		<name>Transitions</name>
		<type>float</type>
		<value>
		    <use>transitions</use>
		</value>
	    </uniform>

	    <uniform>
		<name>InverseSlope</name>
		<type>float</type>
		<value>
		    <use>inverse</use>
		</value>
	    </uniform>

	    <uniform>
		<name>CloudCover0</name>
		<type>float</type>
		<value>
		    <use>cloud-cover0</use>
		</value>
	    </uniform>

	    <uniform>
		<name>CloudCover1</name>
		<type>float</type>
		<value>
		    <use>cloud-cover1</use>
		</value>
	    </uniform>

	    <uniform>
		<name>CloudCover2</name>
		<type>float</type>
		<value>
		    <use>cloud-cover2</use>
		</value>
	    </uniform>

	    <uniform>
		<name>CloudCover3</name>
		<type>float</type>
		<value>
		    <use>cloud-cover3</use>
		</value>
	    </uniform>

	    <uniform>
		<name>CloudCover4</name>
		<type>float</type>
		<value>
		    <use>cloud-cover4</use>
		</value>
	    </uniform>
	</pass>
    </technique>
</PropertyList>