cameraEffects_fp.glsl

/*
===========================================================================
Copyright (C) 2009-2010 Robert Beckebans <trebor_7@users.sourceforge.net>

This file is part of XreaL source code.

XreaL source code is free software; you can redistribute it
and/or modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of the License,
or (at your option) any later version.

XreaL source code 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 General Public License for more details.

You should have received a copy of the GNU General Public License
along with XreaL source code; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
===========================================================================
*/

/* cameraEffects_fp.glsl */

uniform sampler2D u_CurrentMap;

#if defined(r_colorGrading)
uniform sampler3D u_ColorMap3D;
#endif

uniform vec4      u_ColorModulate;
uniform float     u_GlobalLightFactor; // 1 / tr.identityLight
uniform float     u_InverseGamma;

IN(smooth) vec2		var_TexCoords;

DECLARE_OUTPUT(vec4)

/* x: contrast
y: highlightsCompressionSpeed
z: shoulderClip
w: highlightsCompression */
uniform bool u_Tonemap;
uniform vec4 u_TonemapParms;
uniform float u_TonemapExposure;

vec3 TonemapLottes( vec3 color ) {
  // Lottes 2016, "Advanced Techniques and Optimization of HDR Color Pipelines"
  return pow( color, vec3( u_TonemapParms[0] ) )
         / ( pow( color, vec3( u_TonemapParms[0] * u_TonemapParms[1] ) ) * u_TonemapParms[2] + u_TonemapParms[3] );
}

void main()
{
	// calculate the screen texcoord in the 0.0 to 1.0 range
	vec2 st = gl_FragCoord.st / r_FBufSize;

	vec4 color = texture2D(u_CurrentMap, st);
	color *= u_GlobalLightFactor;

	if( u_Tonemap ) {
		color.rgb = TonemapLottes( color.rgb * u_TonemapExposure );
	}
	color.rgb = clamp( color.rgb, vec3( 0.0f ), vec3( 1.0f ) );

#if defined(r_colorGrading)
	// apply color grading
	vec3 colCoord = color.rgb * 15.0 / 16.0 + 0.5 / 16.0;
	colCoord.z *= 0.25;
	color.rgb = u_ColorModulate.x * texture3D(u_ColorMap3D, colCoord).rgb;
	color.rgb += u_ColorModulate.y * texture3D(u_ColorMap3D, colCoord + vec3(0.0, 0.0, 0.25)).rgb;
	color.rgb += u_ColorModulate.z * texture3D(u_ColorMap3D, colCoord + vec3(0.0, 0.0, 0.50)).rgb;
	color.rgb += u_ColorModulate.w * texture3D(u_ColorMap3D, colCoord + vec3(0.0, 0.0, 0.75)).rgb;
#endif

	color.xyz = pow(color.xyz, vec3(u_InverseGamma));

	outputColor = color;
}