/** 
 * @file alphaNonIndexedNoColorF.glsl
 *
 * $LicenseInfo:firstyear=2005&license=viewerlgpl$
 * Second Life Viewer Source Code
 * Copyright (C) 2005, 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
 * $/LicenseInfo$
 */
 
#extension GL_ARB_texture_rectangle : enable

#ifdef DEFINE_GL_FRAGCOLOR
out vec4 frag_color;
#else
#define frag_color gl_FragColor
#endif

uniform float minimum_alpha;

uniform sampler2DRect depthMap;
uniform sampler2D diffuseMap;

uniform vec2 screen_res;

vec3 atmosLighting(vec3 light);
vec3 scaleSoftClip(vec3 light);

VARYING vec3 vary_ambient;
VARYING vec3 vary_directional;
VARYING vec3 vary_fragcoord;
VARYING vec3 vary_position;
VARYING vec3 vary_pointlight_col;
VARYING vec2 vary_texcoord0;

uniform mat4 inv_proj;

vec4 getPosition(vec2 pos_screen)
{
	float depth = texture2DRect(depthMap, pos_screen.xy).a;
	vec2 sc = pos_screen.xy*2.0;
	sc /= screen_res;
	sc -= vec2(1.0,1.0);
	vec4 ndc = vec4(sc.x, sc.y, 2.0*depth-1.0, 1.0);
	vec4 pos = inv_proj * ndc;
	pos /= pos.w;
	pos.w = 1.0;
	return pos;
}

void main() 
{
	vec2 frag = vary_fragcoord.xy/vary_fragcoord.z*0.5+0.5;
	frag *= screen_res;
	
	vec4 pos = vec4(vary_position, 1.0);
	
	vec4 diff= texture2D(diffuseMap,vary_texcoord0.xy);

	if (diff.a < minimum_alpha)
	{
		discard;
	}

	vec4 col = vec4(vary_ambient + vary_directional.rgb, 1.0);
	vec4 color = diff * col;
	
	
	color.rgb = atmosLighting(color.rgb);

	color.rgb = scaleSoftClip(color.rgb);

	color.rgb += diff.rgb * vary_pointlight_col.rgb;

	frag_color = color;
}

