/*
--------------------------------------------------------------------------------
This source file is part of SkyX.
Visit http://www.paradise-studios.net/products/skyx/

Copyright (C) 2009-2012 Xavier Verguín González <xavyiy@gmail.com>

This program is free software; you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License as published by the Free Software
Foundation; either version 2 of the License, or (at your option) any later
version.

This program is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with
this program; if not, write to the Free Software Foundation, Inc., 59 Temple
Place - Suite 330, Boston, MA 02111-1307, USA, or go to
http://www.gnu.org/copyleft/lesser.txt.
--------------------------------------------------------------------------------
*/

#ifdef GL_ES
precision highp int;
precision highp float;
#endif

// ------------------- SkyX volumetric clouds + lightning -----------------------
// ------------------------------ GLSL Vertex -----------------------------------
#define USE_OGRE_FROM_FUTURE
#include <OgreUnifiedShader.h>

OGRE_UNIFORMS(
uniform mat4 uWorldViewProj;
uniform vec3 uCameraPosition;
uniform float uRadius;
)

MAIN_PARAMETERS
IN(vec4 vertex, POSITION)
IN(vec3 uv0, TEXCOORD0)
IN(vec2 uv1, TEXCOORD1)
IN(float uv2, TEXCOORD2)
OUT(vec3 v3DCoord, TEXCOORD0)
OUT(vec2 vNoiseUV, TEXCOORD1)
OUT(float vOpacity, TEXCOORD2)
OUT(vec3 vEyePixel, TEXCOORD3)
OUT(float vDistance, TEXCOORD4)
OUT(vec4 vPositionAtt, TEXCOORD5)
MAIN_DECLARATION
{
  // Clip space position
	gl_Position = mul(uWorldViewProj, vertex);

	// 3D coords
	v3DCoord = uv0;
  // Noise coords
  vNoiseUV = uv1;
  // Opacity
  vOpacity = uv2;
  // Eye to pixel vector
  vEyePixel = normalize(vertex.xyz - uCameraPosition);
  
  // Distance in [0,1] range
  vDistance = length(vec2(vertex.x, vertex.z)) / uRadius;

	vPositionAtt.xyz = vertex.xyz;
	vPositionAtt.w = 225.0 / uRadius;
}