slang-shaders/edge-smoothing/nedi/shaders/nedi-pass1.slang
fishcu 259ff81f4b
Repo reorg: edge smoothing, interpolation, and pixel art scaling (#469)
* Move initial batch of shaders and presets to smoothing subdirectory

* Rename smoothing to edge enhancement

* Move cubic and windowed into interpolation

* Fix some presets

* Fix rest of presets

* Rename edge-enhancement to edge-smoothing

* Move pixel art scalers into separate directory separate from 'interpolation'

* Flatten interpolation/cubic into interpolation/
2023-08-12 18:09:28 -05:00

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#version 450
/*
NEDI Shader - pass1
// This file is a part of MPDN Extensions.
// https://github.com/zachsaw/MPDN_Extensions
//
// 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; either
// version 3.0 of the License, or (at your option) any later version.
//
// 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.
//
Sources ported from this discussion thread:
http://forum.doom9.org/showthread.php?t=170727
Ported by Hyllian - 2015.
*/
layout(push_constant) uniform Push
{
vec4 SourceSize;
vec4 OriginalSize;
vec4 OutputSize;
uint FrameCount;
} params;
layout(std140, set = 0, binding = 0) uniform UBO
{
mat4 MVP;
} global;
#define saturate(c) clamp(c, 0.0, 1.0)
#define lerp(c) mix(c)
#define mul(a,b) (b*a)
#define fmod(c) mod(c)
#define frac(c) fract(c)
#define tex2D(c,d) texture(c,d)
#define float2 vec2
#define float3 vec3
#define float4 vec4
#define int2 ivec2
#define int3 ivec3
#define int4 ivec4
#define bool2 bvec2
#define bool3 bvec3
#define bool4 bvec4
#define float2x2 mat2x2
#define float2x3 mat2x3
#define float3x3 mat3x3
#define float4x4 mat4x4
#define float4x2 mat4x2
#define s0 Source
#define FIX(c) (c * 1.00001)
#define NEDI_WEIGHT2 4.0
#define NEDI_N2 24.0
#define NEDI_E2 0.0
#define NEDI_OFFSET2 0.0
#define ITERATIONS 3
#define WGT 2
#define width (params.SourceSize.x)
#define height (params.SourceSize.y)
#define px (1.0 * (params.SourceSize.z))
#define py (0.4999 * (params.SourceSize.w))
#define offset NEDI_OFFSET2
#define Value(xy) (tex2D(s0,tex+float2(px,py)*(xy)).rgb)//-float4(0,0.4999,0.4999,0))
#define Get(xy) (dot(Value(xy),float3(.2126, .7152, .0722))+offset)
#define Get4(xy) (float2(Get(xy+WGT*dir[0])+Get(xy+WGT*dir[1]),Get(xy+WGT*dir[2])+Get(xy+WGT*dir[3])))
#define sqr(x) (dot(x,x))
#define I (float2x2(1,0,0,1))
//Cramer's method
float2 solve(float2x2 A,float2 b) { return float2(determinant(float2x2(b,A[1])),determinant(float2x2(A[0],b)))/determinant(A); }
#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 * 1.00001;
}
#pragma stage fragment
layout(location = 0) in vec2 vTexCoord;
layout(location = 0) out vec4 FragColor;
layout(set = 0, binding = 2) uniform sampler2D Source;
void main()
{
float2 tex = vTexCoord;
float4 c0 = tex2D(s0,tex);
//Define window and directions
vec2 dir[4] = vec2[4](vec2(-1,0),vec2(1,0),vec2(0,1),vec2(0,-1));
mat4x2 wind1 = mat4x2(vec2(-1,0),vec2(1,0),vec2(0,1),vec2(0,-1));
mat4x2 wind2 = mat4x2(vec2(-2,-1),vec2(2,1),vec2(-1,2),vec2(1,-2));
mat4x2 wind3 = mat4x2(vec2(-3,-2),vec2(3,2),vec2(-2,3),vec2(2,-3));
mat4x2 wind4 = mat4x2(vec2(-2,1),vec2(2,-1),vec2(1,2),vec2(-1,-2));
mat4x2 wind5 = mat4x2(vec2(-3,2),vec2(3,-2),vec2(2,3),vec2(-2,-3));
mat4x2 wind6 = mat4x2(vec2(-4,-1),vec2(4,1),vec2(-1,4),vec2(1,-4));
mat4x2 wind7 = mat4x2(vec2(-4,1),vec2(4,-1),vec2(1,4),vec2(-1,-4));
mat4x2 wind[7] = mat4x2[7](wind1, wind2, wind3, wind4, wind5, wind6, wind7);
/*
wind[1] wind[2]
-3
-2 dir wind[0] 2 1
-1 4 4 4 4
0 1 2 1 2
1 3 3 3 3
2 1 2
3
*/
/*
wind[1] wind[2]
-3 3 1
-2 dir wind[0]
-1 1 4 1 3 1 3
0
1 3 2 2 4 4 2
2
3 2 4
*/
//Initialization
float2x2 R = float2x2(0.,0.,0.,0.);
float2 r = float2(0.,0.);
float m[7] = float[7](NEDI_WEIGHT2, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0);
//Calculate (local) autocorrelation coefficients
for (int k = 0; k<ITERATIONS; k+= 1){
float4 y = float4(Get(wind[k][0]),Get(wind[k][1]),Get(wind[k][2]),Get(wind[k][3]));
float4x2 C = float4x2(Get4(wind[k][0]),Get4(wind[k][1]),Get4(wind[k][2]),Get4(wind[k][3]));
R += mul(transpose(C),m[k]*C);
r += mul(y,m[k]*C);
}
//Normalize
float n = NEDI_N2;
R /= n; r /= n;
//Calculate a = R^-1 . r
float e = NEDI_E2;
float2 a = solve(R+e*e*I,r+e*e/2.0);
//Nomalize 'a' (prevents overshoot)
a = .25 + float2(.4999,-.4999)*clamp(a[0]-a[1],-1.0,1.0);
//Calculate result
float2x3 x = float2x3(Value(dir[0])+Value(dir[1]),Value(dir[2])+Value(dir[3])) * float2x2(a,a);
float3 c = float3(x[0].xyz);
//Skip pixels on wrong grid
if ((frac(tex.x*width/2.0)<0.4999)&&(frac(tex.y*height)<0.4999) || (frac(tex.x*width/2.0)>0.4999)&&(frac(tex.y*height)>0.4999)) FragColor = c0;
else FragColor = float4(c, 1.0);//+float4(0,0.49999,0.49999,0);
}