/** 
 * @file fullbrightV.glsl
 *
 * $LicenseInfo:firstyear=2007&license=viewerlgpl$
 * Second Life Viewer Source Code
 * Copyright (C) 2007, Linden Research, Inc.
 * 
 * This library 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;
 * version 2.1 of the License only.
 * 
 * This library 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 library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 * 
 * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
 * $/LicenseInfo$
 */

uniform mat4 texture_matrix0;
uniform mat4 modelview_matrix;
uniform mat4 modelview_projection_matrix;
uniform bool invert_tex_y = false;
const mat4 invTexM = mat4(
  1, 0, 0, 0,
  0,-1, 0, 0,
  0, 0, 1, 0,
  0, 0, 0, 1
);


ATTRIBUTE vec3 position;
void passTextureIndex();
ATTRIBUTE vec4 diffuse_color;
ATTRIBUTE vec2 texcoord0;

void calcAtmospherics(vec3 inPositionEye);

vec3 atmosAmbient(vec3 light);
vec3 atmosAffectDirectionalLight(float lightIntensity);
vec3 scaleDownLight(vec3 light);
vec3 scaleUpLight(vec3 light);

#ifdef WATER_FOG
VARYING vec3 vary_position;
#endif

VARYING vec4 vertex_color;
VARYING vec2 vary_texcoord0;


void main()
{
	//transform vertex
	vec4 vert = vec4(position.xyz, 1.0);
	vec4 pos = (modelview_matrix * vert);
	passTextureIndex();

	gl_Position = modelview_projection_matrix*vec4(position.xyz, 1.0);

#ifdef WATER_FOG
	vary_position = pos.xyz;
#endif

	vary_texcoord0 = (texture_matrix0 * vec4(texcoord0,0,1)).xy;
  if(invert_tex_y) 
	{
		vary_texcoord0 = vec2(invTexM * vec4(vary_texcoord0,0,1)).xy;
	}
	
	calcAtmospherics(pos.xyz);

	vertex_color = diffuse_color;
}