/** 
 * @file class1/deferred/skyF.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
 * $/LicenseInfo$
 */
 
/*[EXTRA_CODE_HERE]*/

#ifdef DEFINE_GL_FRAGCOLOR
out vec4 frag_data[3];
#else
#define frag_data gl_FragData
#endif

/////////////////////////////////////////////////////////////////////////
// The fragment shader for the sky
/////////////////////////////////////////////////////////////////////////

VARYING vec4 vary_HazeColor;

/// Soft clips the light with a gamma correction
vec3 scaleSoftClip(vec3 light);
vec3 srgb_to_linear(vec3 c);

void main()
{
    // Potential Fill-rate optimization.  Add cloud calculation 
    // back in and output alpha of 0 (so that alpha culling kills 
    // the fragment) if the sky wouldn't show up because the clouds 
    // are fully opaque.

    vec4 color;
    color = vary_HazeColor;

    color.rgb *= 2.;
    color.rgb = scaleSoftClip(color.rgb);

    /// Gamma correct for WL (soft clip effect).
    frag_data[0] = vec4(color.rgb, 0.0);
    frag_data[1] = vec4(0.0,0.0,0.0,0.0);
    frag_data[2] = vec4(0.0,0.0,0.0,1.0); //1.0 in norm.w masks off fog

    gl_FragDepth = 0.99999f;
}