/** 
 * @file fullbrightF.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
 * $/LicenseInfo$
 */
 
#extension GL_ARB_texture_rectangle : enable

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

#if !HAS_DIFFUSE_LOOKUP
uniform sampler2D diffuseMap;
#endif

VARYING vec4 vertex_color;
VARYING vec2 vary_texcoord0;

vec3 fullbrightAtmosTransport(vec3 light);
vec3 fullbrightScaleSoftClip(vec3 light);

vec3 srgb_to_linear(vec3 cs)
{
	
/*        {  cs / 12.92,                 cs <= 0.04045
    cl = {
        {  ((cs + 0.055)/1.055)^2.4,   cs >  0.04045*/

	return pow((cs+vec3(0.055))/vec3(1.055), vec3(2.4));
}

vec3 linear_to_srgb(vec3 cl)
{
	    /*{  0.0,                          0         <= cl
            {  12.92 * c,                    0         <  cl < 0.0031308
    cs = {  1.055 * cl^0.41666 - 0.055,   0.0031308 <= cl < 1
            {  1.0,                                       cl >= 1*/

	return 1.055 * pow(cl, vec3(0.41666)) - 0.055;
}

void main() 
{
#if HAS_DIFFUSE_LOOKUP
	vec4 color = diffuseLookup(vary_texcoord0.xy);
#else
	vec4 color = texture2D(diffuseMap, vary_texcoord0.xy);
#endif

	color.rgb = srgb_to_linear(color.rgb);
	color.rgb *= vertex_color.rgb;

	color.rgb = fullbrightAtmosTransport(color.rgb);
	color.rgb = fullbrightScaleSoftClip(color.rgb);

	color.rgb = linear_to_srgb(color.rgb);

	frag_color.rgb = color.rgb;
	frag_color.a   = color.a;
}