slang-shaders/edge-smoothing/ddt/shaders/ddt-jinc.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
/*
Hyllian's ddt-jinc windowed-jinc 2-lobe with anti-ringing Shader
Copyright (C) 2011-2022 Hyllian/Jararaca - sergiogdb@gmail.com
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.
*/
/*
This is an approximation of Jinc(x)*Jinc(x*r1/r2) for x < 2.5,
where r1 and r2 are the first two zeros of jinc function.
For a jinc 2-lobe best approximation, use A=0.5 and B=0.825.
*/
// A=0.5, B=0.825 is the best jinc approximation for x<2.5. if B=1.0, it's a lanczos filter.
// Increase A to get more blur. Decrease it to get a sharper picture.
// B = 0.825 to get rid of dithering. Increase B to get a fine sharpness, though dithering returns.
layout(push_constant) uniform Push
{
vec4 SourceSize;
vec4 OriginalSize;
vec4 OutputSize;
uint FrameCount;
float JINC2_WINDOW_SINC;
float JINC2_SINC;
float JINC2_AR_STRENGTH;
float DDT_THRESHOLD;
} params;
#pragma parameter JINC2_WINDOW_SINC "Window Sinc Param" 0.50 0.0 1.0 0.01
#define JINC2_WINDOW_SINC params.JINC2_WINDOW_SINC
#pragma parameter JINC2_SINC "Sinc Param" 0.86 0.0 1.0 0.01
#define JINC2_SINC params.JINC2_SINC
#pragma parameter JINC2_AR_STRENGTH "Anti-ringing Strength" 1.0 0.0 1.0 0.1
#define JINC2_AR_STRENGTH params.JINC2_AR_STRENGTH
#pragma parameter DDT_THRESHOLD "DDT Diagonal Threshold" 2.6 1.0 6.0 0.2
#define DDT_THRESHOLD params.DDT_THRESHOLD
layout(std140, set = 0, binding = 0) uniform UBO
{
mat4 MVP;
} global;
#define halfpi 1.5707963267948966192313216916398
#define pi 3.1415926535897932384626433832795
#define wa (JINC2_WINDOW_SINC*pi)
#define wb (JINC2_SINC*pi)
#define WP1 2.0
#define WP2 1.0
#define WP3 -1.0
const vec3 Y = vec3( 0.299, 0.587, 0.114);
float luma(vec3 color)
{
return dot(color, Y);
}
// Calculates the distance between two points
float d(vec2 pt1, vec2 pt2)
{
vec2 v = pt2 - pt1;
return sqrt(dot(v,v));
}
vec3 min4(vec3 a, vec3 b, vec3 c, vec3 d)
{
return min(a, min(b, min(c, d)));
}
vec3 max4(vec3 a, vec3 b, vec3 c, vec3 d)
{
return max(a, max(b, max(c, d)));
}
vec4 resampler(vec4 x)
{
vec4 res;
res.x = (x.x==0.0) ? wa*wb : sin(x.x*wa)*sin(x.x*wb)/(x.x*x.x);
res.y = (x.y==0.0) ? wa*wb : sin(x.y*wa)*sin(x.y*wb)/(x.y*x.y);
res.z = (x.z==0.0) ? wa*wb : sin(x.z*wa)*sin(x.z*wb)/(x.z*x.z);
res.w = (x.w==0.0) ? wa*wb : sin(x.w*wa)*sin(x.w*wb)/(x.w*x.w);
return res;
}
#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 * vec2(1.0001);
}
#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()
{
vec3 color;
mat4x4 weights;
vec2 dx = vec2(1.0, 0.0);
vec2 dy = vec2(0.0, 1.0);
vec2 pc = vTexCoord*params.SourceSize.xy;
vec2 tc = (floor(pc-vec2(0.5,0.5))+vec2(0.5,0.5));
vec2 pos = fract(pc-vec2(0.5,0.5));
weights[0] = resampler(vec4(d(pc, tc -dx -dy), d(pc, tc -dy), d(pc, tc +dx -dy), d(pc, tc+2.0*dx -dy)));
weights[1] = resampler(vec4(d(pc, tc -dx ), d(pc, tc ), d(pc, tc +dx ), d(pc, tc+2.0*dx )));
weights[2] = resampler(vec4(d(pc, tc -dx +dy), d(pc, tc +dy), d(pc, tc +dx +dy), d(pc, tc+2.0*dx +dy)));
weights[3] = resampler(vec4(d(pc, tc -dx+2.0*dy), d(pc, tc +2.0*dy), d(pc, tc +dx+2.0*dy), d(pc, tc+2.0*dx+2.0*dy)));
dx = dx * params.SourceSize.zw;
dy = dy * params.SourceSize.zw;
tc = tc * params.SourceSize.zw;
// reading the texels
vec3 c00 = texture(Source, tc -dx -dy).xyz;
vec3 c10 = texture(Source, tc -dy).xyz;
vec3 c20 = texture(Source, tc +dx -dy).xyz;
vec3 c30 = texture(Source, tc+2.0*dx -dy).xyz;
vec3 c01 = texture(Source, tc -dx ).xyz;
vec3 c11 = texture(Source, tc ).xyz;
vec3 c21 = texture(Source, tc +dx ).xyz;
vec3 c31 = texture(Source, tc+2.0*dx ).xyz;
vec3 c02 = texture(Source, tc -dx +dy).xyz;
vec3 c12 = texture(Source, tc +dy).xyz;
vec3 c22 = texture(Source, tc +dx +dy).xyz;
vec3 c32 = texture(Source, tc+2.0*dx +dy).xyz;
vec3 c03 = texture(Source, tc -dx+2.0*dy).xyz;
vec3 c13 = texture(Source, tc +2.0*dy).xyz;
vec3 c23 = texture(Source, tc +dx+2.0*dy).xyz;
vec3 c33 = texture(Source, tc+2.0*dx+2.0*dy).xyz;
// Get min/max samples
vec3 min_sample = min4(c11, c21, c12, c22);
vec3 max_sample = max4(c11, c21, c12, c22);
float a = luma(c11);
float b = luma(c21);
float c = luma(c12);
float d = luma(c22);
float a1 = luma(c10);
float b1 = luma(c20);
float a0 = luma(c01);
float c0 = luma(c02);
float b2 = luma(c31);
float d2 = luma(c32);
float c3 = luma(c13);
float d3 = luma(c23);
float p = abs(pos.x);
float q = abs(pos.y);
/*
c00 c10 c20 c30 a1 b1
c01 c11 c21 c31 a0 a b b2
c02 c12 c22 c32 c0 c d d2
c03 c13 c23 c33 c3 d3
*/
float wd1 = (WP1*abs(a-d) + WP2*(abs(b-a1) + abs(b-d2) + abs(c-a0) + abs(c-d3)) + WP3*(abs(a1-d2) + abs(a0-d3)));
float wd2 = (WP1*abs(b-c) + WP2*(abs(a-b1) + abs(a-c0) + abs(d-b2) + abs(d-c3)) + WP3*(abs(b1-c0) + abs(b2-c3)));
float irlv1 = (abs(a-b)+abs(a-c)+abs(a-d));
if (((wd1+0.1*DDT_THRESHOLD)*DDT_THRESHOLD < wd2) && (irlv1 > 0.0))
{
if (q <= p)
{
c12 = c11 + c22 - c21;
c01 = c11 + c00 - c10;
c23 = c22 + c33 - c32;
c03 = c13 + c02 - c12;
}
else
{
c21 = c11 + c22 - c12;
c10 = c11 + c00 - c01;
c32 = c22 + c33 - c23;
c30 = c31 + c20 - c21;
}
}
else if ((wd1 > (wd2+0.1*DDT_THRESHOLD)*DDT_THRESHOLD) && (irlv1 > 0.0))
{
if ((p+q) < 1.0)
{
c22 = c21 + c12 - c11;
c31 = c21 + c30 - c20;
c13 = c12 + c03 - c02;
c33 = c23 + c32 - c22;
}
else
{
c11 = c21 + c12 - c22;
c20 = c21 + c30 - c31;
c02 = c12 + c03 - c13;
c00 = c10 + c01 - c11;
}
}
color = mat4x3(c00, c10, c20, c30) * weights[0];
color+= mat4x3(c01, c11, c21, c31) * weights[1];
color+= mat4x3(c02, c12, c22, c32) * weights[2];
color+= mat4x3(c03, c13, c23, c33) * weights[3];
color = color/(dot(weights * vec4(1.0), vec4(1.0)));
// Anti-ringing
vec3 aux = color;
color = clamp(color, min_sample, max_sample);
color = mix(aux, color, JINC2_AR_STRENGTH);
// final sum and weight normalization
FragColor = vec4(color, 1.0);
}