#version 450

/*
   CRT Color Profiles
   
   Copyright (C) 2019 guest(r) and Dr. Venom
   
   This program 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.

   This program 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 this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
   
*/ 

layout(push_constant) uniform Push
{
   float CP, CS;
} params;

#pragma parameter CP "CRT Color Profile" 0.0 -1.0 5.0 1.0 
#pragma parameter CS "Color Space: sRGB, DCI, Adobe, Rec.2020" 0.0 0.0 3.0 1.0 

#define CP params.CP
#define CS params.CS

#define COMPAT_TEXTURE(c,d) texture(c,d)
#define TEX0 vTexCoord

layout(std140, set = 0, binding = 0) uniform UBO
{
	mat4 MVP;
} global;

#pragma stage vertex
layout(location = 0) in vec4 Position;
layout(location = 1) in vec2 TexCoord;
layout(location = 0) out vec2 vTexCoord;

void main()
{
   gl_Position = global.MVP * Position;
   vTexCoord = TexCoord;
}

#pragma stage fragment
layout(location = 0) in vec2 vTexCoord;
layout(location = 0) out vec4 FragColor;
layout(set = 0, binding = 2) uniform sampler2D Source;

const mat3 Profile0 = 
mat3(
 0.412391,  0.212639,  0.019331,
 0.357584,  0.715169,  0.119195,
 0.180481,  0.072192,  0.950532
);

const mat3 Profile1 = 
mat3(
 0.430554,  0.222004,  0.020182,
 0.341550,  0.706655,  0.129553,
 0.178352,  0.071341,  0.939322
);

const mat3 Profile2 = 
mat3(
 0.396686,  0.210299,  0.006131,
 0.372504,  0.713766,  0.115356,
 0.181266,  0.075936,  0.967571
);

const mat3 Profile3 = 
mat3(
 0.393521,  0.212376,  0.018739,
 0.365258,  0.701060,  0.111934,
 0.191677,  0.086564,  0.958385
);

const mat3 Profile4 = 
mat3(
 0.392258,  0.209410,  0.016061,
 0.351135,  0.725680,  0.093636,
 0.166603,  0.064910,  0.850324
);

const mat3 Profile5 = 
mat3(
 0.377923,  0.195679,  0.010514,
 0.317366,  0.722319,  0.097826,
 0.207738,  0.082002,  1.076960
);

const mat3 ToSRGB = 
mat3(
 3.240970, -0.969244,  0.055630,
-1.537383,  1.875968, -0.203977,
-0.498611,  0.041555,  1.056972
);

const mat3 ToDCI = 
mat3(
 2.725394,  -0.795168,   0.041242,
-1.018003,   1.689732,  -0.087639,
-0.440163,   0.022647,   1.100929
);

const mat3 ToAdobe = 
mat3(
 2.041588, -0.969244,  0.013444,
-0.565007,  1.875968, -0.11836,
-0.344731,  0.041555,  1.015175
);

const mat3 ToREC = 
mat3(
 1.716651, -0.666684,  0.017640,
-0.355671,  1.616481, -0.042771,
-0.253366,  0.015769,  0.942103
);

void main()
{
	vec3 c = COMPAT_TEXTURE(Source, TEX0.xy).rgb;
	
	float p;
	mat3 m_out;
	
	if (CS == 0.0) { p = 2.4; m_out =  ToSRGB; } else
	if (CS == 1.0) { p = 2.6; m_out =  ToDCI;  } else
	if (CS == 2.0) { p = 2.2; m_out =  ToAdobe;} else
	if (CS == 3.0) { p = 2.4; m_out =  ToREC;  }
	
	vec3 color = pow(c, vec3(p));
	
	mat3 m_in = Profile0;

	if (CP == 0.0) { m_in = Profile0; } else	
	if (CP == 1.0) { m_in = Profile1; } else
	if (CP == 2.0) { m_in = Profile2; } else
	if (CP == 3.0) { m_in = Profile3; } else
	if (CP == 4.0) { m_in = Profile4; } else
	if (CP == 5.0) { m_in = Profile5; }
	
	color = m_in*color;
	color = m_out*color;

	color = pow(color, vec3(1.0/p));	
	
	if (CP == -1.0) color = c;
	
	FragColor = vec4(color,1.0);
}