/*
--------------------------------------------------------------------------------
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 -----------------------------
// ------------------------------ 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)
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;
}