Update fake-crt-geom-potato.slang (#425)

* Update fake-crt-geom-potato.slang

* add retro-palettes

* Add EGA filter with dithering

crt/shaders/fake-crt-geom-potato.slang

@@ -19,12 +19,13 @@ layout(push_constant) uniform Push
 #pragma parameter boost "Bright boost " 1.00 1.00 2.00 0.02
 #define boost params.boost
 
-#pragma parameter SCANLINE "Scanline Intensity" 0.30 0.0 1.0 0.05
+#pragma parameter SCANLINE "Scanline Intensity" 0.70 0.0 1.0 0.05
 #define SCANLINE params.SCANLINE
 
-#pragma parameter cgwg "CGWG mask brightness " 0.7 0.0 1.0 0.1
+#pragma parameter cgwg "Mask Intensity " 0.8 0.0 1.0 0.05
 #define cgwg params.cgwg
 
+
 #define pi 3.141592654
 	
 layout(std140, set = 0, binding = 0) uniform UBO
@@ -36,47 +37,38 @@ layout(std140, set = 0, binding = 0) uniform UBO
 layout(location = 0) in vec4 Position;
 layout(location = 1) in vec2 TexCoord;
 layout(location = 0) out vec2 vTexCoord;
-layout(location = 1) out float omega;
+layout(location = 1) out vec2 p;
 
 void main()
 {
 	gl_Position = global.MVP * Position;
 	vTexCoord = TexCoord * 1.0001;
-	omega =   pi * params.SourceSize.y * 2.0;
+        p = vTexCoord * params.SourceSize.xy;
 }
 
 #pragma stage fragment
 layout(location = 0) in vec2 vTexCoord;
-layout(location = 1) in float omega;
 layout(location = 0) out vec4 FragColor;
+layout(location = 1) in vec2 p;
+
 layout(set = 0, binding = 1) uniform sampler2D Source;
 
 
 ///////////////////////////////////////////////////////////////////////////////////////////////
 
-// CGWG mask calculation
-	
-      vec3 Mask(float pos)
-      {
-	
-      float mf = fract(pos * 0.5);
-
-      if (mf <0.5) return vec3(1.0,cgwg,1.0);
-      else return vec3(cgwg,1.0,cgwg);
-  
-      }
 
 void main()
 {
 	vec2 pos = vTexCoord.xy;
+
 	vec3 res = texture(Source, pos).rgb;
 
-	if (params.OriginalSize.y < 400.0)
+	res *=res;
-	res = res * (1.0 + SCANLINE * sin(pos.y * omega));
+    res *= SCANLINE * sin(fract(p.y)*pi) +(1.0-SCANLINE);
-	else res;
 
 // apply the mask
-	res *= Mask(pos.x*params.OutputSize.x * 1.0001);
+	res *= cgwg * sin(fract(pos.x*0.5*params.OutputSize.x)*pi) +(1.0-cgwg);
+    res = sqrt(res);
 	res *= boost;
 
     FragColor = vec4(res,1.0);

misc/ega.slangp

@@ -0,0 +1,4 @@
+shaders = 1
+
+shader0 = shaders/ega.slang
+scale_type0 = source

misc/retro-palettes.slangp

@@ -0,0 +1,4 @@
+shaders = 1
+
+shader0 = shaders/retro-palettes.slang
+scale_type0 = source

misc/shaders/ega.slang

@@ -0,0 +1,132 @@
+#version 450
+
+layout(push_constant) uniform Push
+{
+  vec4 SourceSize;
+  vec4 OriginalSize;
+  vec4 OutputSize;
+  uint FrameCount;
+
+} params;
+
+#define _ 0.0
+#define o (1./3.)
+#define b (2./3.)
+#define B 1.0
+
+#define color_enhance 1.0
+#define SourceSize params.SourceSize
+
+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*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;
+
+
+// Color lookup table (RGBI palette with brown fix)
+const vec3 rgbi_palette[19] = 
+{
+  vec3(_, _, _),
+  vec3(_, _, b),
+  vec3(_, b, _),
+  vec3(_, b, _),
+  vec3(_, b, _),
+  vec3(_, b, _),
+  vec3(_, b, b),
+  vec3(b, _, _),
+  vec3(b, _, b),
+  vec3(b, o, _),
+  vec3(b, b, b),
+  vec3(o, o, o),
+  vec3(o, o, B),
+  vec3(o, B, o),
+  vec3(o, B, B),
+  vec3(B, o, o),
+  vec3(B, o, B),
+  vec3(B, B, o),
+  vec3(B, B, B),
+};
+
+
+// Came off the wikipedia(R) article for Ordered_Dithering
+const int dithertable[16] = 
+{
+	 1, 9, 3,11,
+	13, 5,15, 7,
+	 4,12, 2,10,
+  16, 8,14, 6,
+};
+
+
+// Compare vector distances and return nearest RGBI color
+vec3 nearest_rgbi (vec3 original) 
+{
+  float dst;
+  float min_dst = 2.0;
+  int idx = 0;
+  for (int i=0; i<19; i++) 
+  {
+    dst = distance(original, rgbi_palette[i]);
+    if (dst < min_dst) 
+     {
+      min_dst = dst;
+      idx = i;
+     }
+  }
+  return rgbi_palette[idx];
+}
+
+
+float modu(float x, float y)
+{
+	return x - y * floor(x/y);
+}
+
+//fragment
+void main()
+{
+  vec3 color = texture(Source, vTexCoord.xy).rgb;
+
+	// leilei - dither 
+	vec2 res;
+	vec2 tex=vTexCoord.xy;
+	res.x = SourceSize.x; 
+
+	if (SourceSize.y < 900.0)
+		res.y = SourceSize.y; 
+	   else
+	     res.y = SourceSize.y / 2.0; 
+
+	int ohyes;
+  int i;
+  vec2 ditheu = tex.xy * res.xy;
+
+  int ditdex =  int(modu(ditheu.x, 4))*4 + int(modu(ditheu.y, 4)); // 4x4!
+
+  // looping through a lookup table matrix
+  
+  for (i = ditdex; i < (ditdex+16); i = i+1) 
+      ohyes = dithertable[i-15] * 2 - 21;
+      ohyes = ohyes - 6;
+      
+      color *= 255.0;
+      color += ohyes;
+      color /= 255.0;
+  FragColor = vec4(nearest_rgbi(color*color_enhance), 1.0);
+}

misc/shaders/retro-palettes.slang

@@ -0,0 +1,47 @@
+#version 450
+
+layout(push_constant) uniform Push
+{
+	vec4 SourceSize;
+	vec4 OriginalSize;
+	vec4 OutputSize;
+	uint FrameCount;
+	float pal;
+} params;
+
+#pragma parameter pal "color palette colors: (1+x)^3" 1.0 1.0 15.0 1.0
+#pragma parameter something "1: ZX Spectrum, 2: Amstrad, 3: EGA, 7:Genesis, 15:Amiga" 0.0 0.0 0.0 0.0
+#define pal params.pal
+
+#define SourceSize params.SourceSize
+#define OutputSize params.OutputSize
+#define OriginalSize params.OriginalSize
+
+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*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 res = texture(Source,vTexCoord).rgb;
+
+  	res= round(res*pal)/pal;
+   FragColor = vec4(res,1.0);
+}