update ntsc-feather (#242)

* Update ntsc-feather.glsl

* Update ntsc-feather.glslp

* add simple-dither

* Add files via upload

* Update ntsc-feather.glsl

* Update simple_dither.glsl

dithering/shaders/simple_dither.glsl

@@ -0,0 +1,133 @@
+#version 110
+
+/*
+   Simple dither shader by DariusG 2023
+   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.
+*/
+
+#pragma parameter threshold "threshold" 0.2 0.0 3.0 1.0 
+
+#define iTime float(FrameCount)
+#define pi 3.141592
+#if defined(VERTEX)
+
+#if __VERSION__ >= 130
+#define COMPAT_VARYING out
+#define COMPAT_ATTRIBUTE in
+#define COMPAT_TEXTURE texture
+#else
+#define COMPAT_VARYING varying 
+#define COMPAT_ATTRIBUTE attribute 
+#define COMPAT_TEXTURE texture2D
+#endif
+
+#ifdef GL_ES
+#define COMPAT_PRECISION mediump
+#else
+#define COMPAT_PRECISION
+#endif
+
+COMPAT_ATTRIBUTE vec4 VertexCoord;
+COMPAT_ATTRIBUTE vec4 COLOR;
+COMPAT_ATTRIBUTE vec4 TexCoord;
+COMPAT_VARYING vec4 COL0;
+COMPAT_VARYING vec4 TEX0;
+
+vec4 _oPosition1; 
+uniform mat4 MVPMatrix;
+uniform COMPAT_PRECISION int FrameDirection;
+uniform COMPAT_PRECISION int FrameCount;
+uniform COMPAT_PRECISION vec2 OutputSize;
+uniform COMPAT_PRECISION vec2 TextureSize;
+uniform COMPAT_PRECISION vec2 InputSize;
+
+// compatibility #defines
+#define vTexCoord TEX0.xy
+#define SourceSize vec4(TextureSize, 1.0 / TextureSize) //either TextureSize or InputSize
+#define OutSize vec4(OutputSize, 1.0 / OutputSize)
+
+void main()
+{
+    gl_Position = MVPMatrix * VertexCoord;
+    TEX0.xy = TexCoord.xy;
+}
+
+#elif defined(FRAGMENT)
+
+#if __VERSION__ >= 130
+#define COMPAT_VARYING in
+#define COMPAT_TEXTURE texture
+out vec4 FragColor;
+#else
+#define COMPAT_VARYING varying
+#define FragColor gl_FragColor
+#define COMPAT_TEXTURE texture2D
+#endif
+
+#ifdef GL_ES
+#ifdef GL_FRAGMENT_PRECISION_HIGH
+precision highp float;
+#else
+precision mediump float;
+#endif
+#define COMPAT_PRECISION mediump
+#else
+#define COMPAT_PRECISION
+#endif
+
+uniform COMPAT_PRECISION int FrameDirection;
+uniform COMPAT_PRECISION int FrameCount;
+uniform COMPAT_PRECISION vec2 OutputSize;
+uniform COMPAT_PRECISION vec2 TextureSize;
+uniform COMPAT_PRECISION vec2 InputSize;
+uniform sampler2D Texture;
+COMPAT_VARYING vec4 TEX0;
+
+// compatibility #defines
+#define Source Texture
+#define vTexCoord TEX0.xy
+
+#define SourceSize vec4(TextureSize, 1.0 / TextureSize) //either TextureSize or InputSize
+#define OutSize vec4(OutputSize, 1.0 / OutputSize)
+
+#ifdef PARAMETER_UNIFORM
+uniform COMPAT_PRECISION float threshold;
+
+#else
+#define threshold 0.1
+#endif
+
+
+
+/*blurry dither
+vec3 dith = vec3(.0);
+float counter = 1.0;
+for (int x = -1; x<2; x++)
+{
+    vec2 uv = vec2(vTexCoord.x*SourceSize.x+float(x), vTexCoord.y*SourceSize.y)/SourceSize.xy;    
+    dith += texture2D(Source,uv).rgb;
+    counter = counter+1.0;   
+}
+    res = (res+dith)/counter;
+*/ 
+
+void main()
+{
+vec2 pos = vTexCoord;
+vec3 res = COMPAT_TEXTURE(Source,pos).rgb;
+vec3 left = COMPAT_TEXTURE(Source,pos - vec2(SourceSize.z, 0.0)).rgb;
+vec3 right = COMPAT_TEXTURE(Source,pos + vec2(SourceSize.z, 0.0)).rgb;
+vec3 lleft = COMPAT_TEXTURE(Source,pos - vec2(SourceSize.z*2.0, 0.0)).rgb;
+vec3 rright = COMPAT_TEXTURE(Source,pos + vec2(SourceSize.z*2.0, 0.0)).rgb;
+
+float leftv = left.r + left.g + left.b;
+float rightv = right.r + right.g + right.b;
+
+if (abs(leftv-rightv) < threshold) res = (res+right)/2.0;
+
+FragColor = vec4(res,1.0);
+}
+#endif

dithering/simple_dither.glslp

@@ -0,0 +1,5 @@
+shaders = 1_
+shader0 = shaders/simple_dither.glsl
+filter_linear0 = false
+scale_type0 = source
+scale0 = 1.0

ntsc/ntsc-feather.glslp

@@ -1,5 +1,5 @@
 shaders = 1
 shader0 = shaders/ntsc-simple/ntsc-feather.glsl
 
-filter_linear0 = true 
+filter_linear0 = false 
 scale_type0 = source

ntsc/shaders/ntsc-simple/ntsc-feather.glsl

@@ -7,6 +7,9 @@
    Software Foundation; either version 2 of the License, or (at your option)
    any later version.
 */
+
+#define iTime float(FrameCount)
+#define pi 3.141592
 #if defined(VERTEX)
 
 #if __VERSION__ >= 130
@@ -89,104 +92,45 @@ COMPAT_VARYING vec4 TEX0;
 #define OutSize vec4(OutputSize, 1.0 / OutputSize)
 
 #ifdef PARAMETER_UNIFORM
-uniform COMPAT_PRECISION float bleeding;
+uniform COMPAT_PRECISION float GLITCH;
 
 #else
-#define bleeding 0.5
+#define GLITCH 0.1
 #endif
 
-#define PI 3.14159265
-#define _Framecount float (FrameCount)
 
+const mat3 rgb2yuv = mat3(0.299,-0.14713, 0.615,
+                           0.587,-0.28886,-0.51499,
+                           0.114, 0.436  ,-0.10001);
 
-float RGB2Y(vec3 _rgb) {
-    return dot(_rgb, vec3(0.29900, 0.58700, 0.11400));
-}
+const mat3 yuv2rgb = mat3(1.0, 1.0, 1.0,
+                 0.0,-0.39465,2.03211,
+                 1.13983,-0.58060,0.0);
 
-float RGB2U(vec3 _rgb) {
-   return dot(_rgb, vec3(-0.14713, -0.28886, 0.43600));
-}
+void main()
+{
+vec2 pos = vTexCoord;
 
-float RGB2V(vec3 _rgb) {
-   return dot(_rgb, vec3(0.61500, -0.51499, -0.10001));
-}
+vec3 res = texture2D(Source,pos).rgb;
 
-float YUV2R(vec3 _yuv) {
-   return dot(_yuv, vec3(1, 0.00000, 1.13983));
-}
+vec3 leftp = COMPAT_TEXTURE(Source,pos-vec2(SourceSize.z,0.0)).rgb;
+vec3 rightp = COMPAT_TEXTURE(Source,pos+vec2(SourceSize.z,0.0)).rgb;
+vec3 dither = (leftp+rightp)/2.0;
 
-float YUV2G(vec3 _yuv) {
-   return dot(_yuv, vec3(1.0, -0.39465, -0.58060));
-}
+res = rgb2yuv*res; dither =rgb2yuv*dither;
+res =dither*0.49+res*0.51; //just keep a tiny evidence of dither
 
-float YUV2B(vec3 _yuv) {
-    return dot(_yuv, vec3(1.0, 2.03211, 0.00000));
-}
+vec3 check = COMPAT_TEXTURE(Source, pos + vec2(SourceSize.z,0.0)).rgb; 
+check = rgb2yuv*check;
 
-vec3 YUV2RGB(vec3 _yuv) {
-    vec3 _rgb;
-    _rgb.r = YUV2R(_yuv);
-    _rgb.g = YUV2G(_yuv);
-    _rgb.b = YUV2B(_yuv);
+float lum_diff= abs(check.r-res.r); 
+float chr_diff= abs(check.g-res.g); 
 
-   return _rgb;
-}
+//flicker on luma/chroma difference
+res +=lum_diff*abs(sin(iTime))*0.1;
+res +=chr_diff*abs(sin(iTime))*0.1;
 
-
-
-
-void main() {
-    float a_kernel[5];
-    a_kernel[0] = 2.0; 
-    a_kernel[1] = 4.0; 
-    a_kernel[2] = 1.0; 
-    a_kernel[3] = 4.0; 
-    a_kernel[4] = 2.0; 
-    
-    vec2 pos = vTexCoord;
-    float y = pos.y*SourceSize.y;
-    float cent=floor(y)+0.5;
-    y = cent*SourceSize.w;
-    vec2 coords = vec2(pos.x,mix(pos.y,y,0.3));
-    vec4 res;
-    float factor = InputSize.y/SourceSize.y;
-//sawtooth effect
-    if( mod( floor(coords.y*OutputSize.y/factor), 2.0 ) == 0.0 ) {
-        res = texture2D( Source, coords + vec2(OutSize.z*0.5*factor, 0.0) );
-    } else {
-        res = texture2D( Source, coords - vec2(OutSize.z*0.5*factor, 0.0) );
-    }
-//end of sawtooth
-    
-// blur image 
-    vec2 fragCoord = coords*OutputSize.xy;
-    float counter = 1.0;
-    for (int i = -2; i <= 2; i++) {
-            vec2 uv = vec2(fragCoord.x + float(i)*0.5*factor, fragCoord.y ) / OutputSize.xy;
-            res.rgb += texture2D(Source, uv).xyz;
-            counter += 1.0;
-    }
-    res.rgb /= counter;
-//blur end
-
-
-    vec3 yuv = vec3(0.0);
-
-//color bleed   
-    float px = 0.0;
-    for( int x = -1; x <= 1; x++ ) {
-        px = float(x) * SourceSize.z - SourceSize.w * 0.5;
-        yuv.g += RGB2U( texture2D( Source, coords + vec2(px*factor, 0.0)).rgb ) * a_kernel[x + 2];
-        yuv.b += RGB2V( texture2D( Source, coords + vec2(px*factor, 0.0)).rgb ) * a_kernel[x + 2];
-    }
-    
-    yuv.r = RGB2Y(res.rgb);
-    yuv.g /= 10.0;
-    yuv.b /= 10.0;
-
-    res.rgb = (res.rgb * (1.0 - 0.5)) + (YUV2RGB(yuv) * 0.5);
-//color bleed end    
-    
-    FragColor = res;
+res = yuv2rgb*res;
+FragColor = vec4(res,1.0);
 }
 #endif