Add gamma slider on checkerboard-dedither (#295)

* Add Retro-Tiles shaders

A shader designed for handheld and low res systems. It turns pixels into crisp tiles.

* Add box scaling

- Turn mandatory integer scaling;
- Add Overscan option.

* Fix gamma on retro-tiles shader

- Increased gamma from 2.2 to 2.7 for a better white balance.

* Add Gamma Slider to checkerboard-dedither

- Add Gamma Slider to checkerboard-dedither.

* Update checkerboard-dedither shaders

- Add new pattern recognitions;
- Add new option to mitigate false positives.

dithering/shaders/checkerboard-dedither/checkerboard-dedither-pass1.slang

@@ -36,8 +36,7 @@ layout(push_constant) uniform Push
     float CD_BLEND_LEVEL;
 } params;
 
-#pragma parameter CB-DEDITHER                 "[CHECKERBOARD-DEDITHER PARAMS]" 0.0 0.0 0.0 0.0
+#pragma parameter CD_BLEND_OPTION    "CHECKERBOARD-DEDITHER: [ OFF | ON ]" 1.0  0.0 1.0  1.0
-#pragma parameter CD_BLEND_OPTION             "    [ OFF | ON ]"               1.0  0.0 1.0  1.0
 #pragma parameter CD_BLEND_LEVEL     "    Blend Level"                     1.0  0.0 1.0  0.1
 
 #define CD_BLEND_OPTION             params.CD_BLEND_OPTION
@@ -88,23 +87,19 @@ void main()
 
     vec3 color = C;
 
-	//  Get min/max samples
+    if (CD_BLEND_OPTION == 1)
-	vec3 min_sample = min_s(C, L, R);
+    {
-	vec3 max_sample = max_s(C, L, R);
+        float diff = dot(max(C, max(L, R)) - min(C, min(L, R)), Y);
-
-	float diff = dot(max(max(C, L), max(C, R)) - min(min(C, L), min(C, R)), Y);
 
         diff *= (1.0 - CD_BLEND_LEVEL);
 
-	if (CD_BLEND_OPTION == 1)
+        vec3 min_sample = max(min_s(C, L, R), min_s(C, U, D));
-	{
+        vec3 max_sample = min(max_s(C, L, R), max_s(C, U, D));
-		min_sample = max(min_sample, min_s(C, U, D));
-		max_sample = min(max_sample, max_s(C, U, D));
 
         color = 0.5*( 1.0 + diff )*C + 0.125*( 1.0 - diff )*(L + R + U + D);
-	}
 
         color = clamp(color, min_sample, max_sample);
+    }
 
     float luma_diff = abs(dot(C, Y)-dot(color, Y));
 

dithering/shaders/checkerboard-dedither/checkerboard-dedither-pass2.slang

@@ -39,12 +39,11 @@ layout(push_constant) uniform Push
 
 #define CD_BLEND_LEVEL             params.CD_BLEND_LEVEL
 
+#define PATTERN(A)                 step(Delta,A)
+
 const float Delta = 0.000000001;
 const vec3 Y = vec3( 0.299,  0.587,  0.114);
 
-vec3 min_s(vec3 central, vec3 adj1, vec3 adj2) {return min(central, max(adj1, adj2));}
-vec3 max_s(vec3 central, vec3 adj1, vec3 adj2) {return max(central, min(adj1, adj2));}
-
 layout(std140, set = 0, binding = 0) uniform UBO
 {
     mat4 MVP;
@@ -84,6 +83,21 @@ void main()
     vec4 DL = texture(Source, vTexCoord -dx +dy);
     vec4 DR = texture(Source, vTexCoord +dx +dy);
 
+    vec4 L2 =  texture(Source, vTexCoord -2.0*dx    );
+    vec4 R2 =  texture(Source, vTexCoord +2.0*dx    );
+    vec4 U2 =  texture(Source, vTexCoord     -2.0*dy);
+    vec4 D2 =  texture(Source, vTexCoord     +2.0*dy);
+
+    vec4 UL2 =  texture(Source, vTexCoord -2.0*dx -dy);
+    vec4 UR2 =  texture(Source, vTexCoord +2.0*dx -dy);
+    vec4 DL2 =  texture(Source, vTexCoord -2.0*dx +dy);
+    vec4 DR2 =  texture(Source, vTexCoord +2.0*dx +dy);
+
+    vec4 LU2 =  texture(Source, vTexCoord -dx -2.0*dy);
+    vec4 RU2 =  texture(Source, vTexCoord +dx -2.0*dy);
+    vec4 LD2 =  texture(Source, vTexCoord -dx +2.0*dy);
+    vec4 RD2 =  texture(Source, vTexCoord +dx -2.0*dy);
+
     vec3 color =  C.rgb;
 
     vec3 oriC = texture(LinearGamma, vTexCoord        ).rgb;
@@ -97,23 +111,29 @@ void main()
 
     float diff  = (1.0 - CD_BLEND_LEVEL);
 
-//  UL  U UR
+//      LU2  U2  RU2
-//   L  C  R
+//  UL2  UL   U  UR  UR2
-//  DL  D DR
+//   L2   L   C   R   R2
+//  DL2  DL   D  DR  DR2
+//      LD2  D2  RD2
 
-	count1 += (step(Delta, L.a*D.a*R.a));
+    count1 += PATTERN(L.a*D.a*R.a);
-	count1 += (step(Delta, L.a*U.a*R.a));
+    count1 += PATTERN(L.a*U.a*R.a);
-	count1 += (step(Delta, L.a*UL.a*R.a*UR.a + L.a*DL.a*R.a*DR.a));
+    count1 += PATTERN(L.a*UL.a*R.a*UR.a + L.a*DL.a*R.a*DR.a);
 
-	count2 += (step(Delta, U.a*L.a*D.a));
+    count1 += PATTERN(U.a*D2.a*(UL.a*LD2.a + UR.a*RD2.a) + U2.a*D.a*(LU2.a*DL.a + RU2.a*DR.a));
-	count2 += (step(Delta, U.a*R.a*D.a));
-	count2 += (step(Delta, U.a*UR.a*D.a*DR.a + D.a*DL.a*U.a*UL.a));
 
-	if ((count1 * count2) > 0.0)
+    count2 += PATTERN(U.a*L.a*D.a);
+    count2 += PATTERN(U.a*R.a*D.a);
+    count2 += PATTERN(U.a*UR.a*D.a*DR.a + D.a*DL.a*U.a*UL.a);
+
+    count2 += PATTERN(L.a*R2.a*(DL.a*DR2.a + UL.a*UR2.a) + L2.a*R.a*(DL2.a*DR.a + UL2.a*UR.a));
+
+    if ((count1 * count2) > 0.0 && count1 == count2)
         color = 0.5*(1.0+diff)*oriC + 0.125*(1.0-diff)*(oriL + oriR + oriU + oriD);
-	else if (count1 > 0.0)
+    else if (count1 > 0.0 && count1 > count2)
         color = 0.5*(1.0+diff)*oriC + 0.25*(1.0-diff)*(oriL + oriR);
-	else if (count2 > 0.0)
+    else if (count2 > 0.0 && count2 > count1)
         color = 0.5*(1.0+diff)*oriC + 0.25*(1.0-diff)*(oriU + oriD);
 
     float luma_diff = abs(dot(oriC, Y)-dot(color, Y));

dithering/shaders/checkerboard-dedither/checkerboard-dedither-pass3.slang

@@ -32,26 +32,30 @@ layout(push_constant) uniform Push
     vec4 OriginalSize;
     vec4 OutputSize;
     uint FrameCount;
-	float CD_HUD_DETAILS;
+    float CD_MITIG_NEIGHBRS;
+    float CD_MITIG_LINES;
     float CD_ADJUST_VIEW;
+    float UseGamma;
 } params;
 
-#pragma parameter CD_HUD_DETAILS               "    Details Threshold"          1.0  0.0 5.0  1.0
+#pragma parameter CD_MITIG_NEIGHBRS            "    Mitigate Errors (neighbors)" 1.0  0.0 4.0  1.0
+#pragma parameter CD_MITIG_LINES               "    Mitigate Errors (regions)"   0.0  0.0 1.0  1.0
 #pragma parameter CD_ADJUST_VIEW               "    Adjust View"                 0.0  0.0 1.0  1.0
+#pragma parameter UseGamma                     "    Gamma Slider"                1.0  0.0 1.0  0.1
 
-#define CD_HUD_DETAILS             params.CD_HUD_DETAILS
+#define CD_MITIG_NEIGHBRS   params.CD_MITIG_NEIGHBRS
+#define CD_MITIG_LINES      params.CD_MITIG_LINES
 #define CD_ADJUST_VIEW      params.CD_ADJUST_VIEW
+#define UseGamma            params.UseGamma
+#define OuputGamma          (UseGamma+1.0)
 
-#define GAMMA_EXP		2.0
+#define GAMMA_OUT(color)    pow(color, vec3(1.0 / OuputGamma, 1.0 / OuputGamma, 1.0 / OuputGamma))
-#define GAMMA_IN(color)		pow(color, vec3(GAMMA_EXP, GAMMA_EXP, GAMMA_EXP))
+
-#define GAMMA_OUT(color)	pow(color, vec3(1.0 / GAMMA_EXP, 1.0 / GAMMA_EXP, 1.0 / GAMMA_EXP))
+#define PATTERN(A)          step(Delta,A)
 
 const float Delta = 0.000000001;
 const vec3 Y = vec3( 0.299,  0.587,  0.114);
 
-vec3 min_s(vec3 central, vec3 adj1, vec3 adj2) {return min(central, max(adj1, adj2));}
-vec3 max_s(vec3 central, vec3 adj1, vec3 adj2) {return max(central, min(adj1, adj2));}
-
 layout(std140, set = 0, binding = 0) uniform UBO
 {
     mat4 MVP;
@@ -91,26 +95,53 @@ void main()
     vec4 DL = texture(Source, vTexCoord -dx +dy);
     vec4 DR = texture(Source, vTexCoord +dx +dy);
 
+    vec4 L2 =  texture(Source, vTexCoord -2.0*dx    );
+    vec4 R2 =  texture(Source, vTexCoord +2.0*dx    );
+    vec4 U2 =  texture(Source, vTexCoord     -2.0*dy);
+    vec4 D2 =  texture(Source, vTexCoord     +2.0*dy);
+
+    vec4 L3 =  texture(Source, vTexCoord -3.0*dx    );
+    vec4 R3 =  texture(Source, vTexCoord +3.0*dx    );
+    vec4 U3 =  texture(Source, vTexCoord     -3.0*dy);
+    vec4 D3 =  texture(Source, vTexCoord     +3.0*dy);
+
     vec3 color =  C.rgb;
 
     vec3 oriC = texture(LinearGamma, vTexCoord        ).rgb;
 
     float count   = 0.0;
     float count2  = 0.0;
+    float count3  = 0.0;
 
+//              U3
+//              U2     
 //          UL   U  UR     
-//   L  C  R
+//  L3  L2   L   C   R   R2  R3
 //          DL   D  DR     
+//              D2     
+//              D3
 
-	count += step(Delta, L.a);
+    count += PATTERN(L.a);
-	count += step(Delta, R.a);
+    count += PATTERN(R.a);
-	count += step(Delta, U.a);
+    count += PATTERN(U.a);
-	count += step(Delta, D.a);
+    count += PATTERN(D.a);
-	count += step(Delta, UL.a*UR.a*DL.a*DR.a);
+    count += PATTERN(UL.a*UR.a*DL.a*DR.a);
 
-	count2 += (step(Delta, L.a*UL.a*U.a + U.a*UR.a*R.a + R.a*DR.a*D.a + D.a*DL.a*L.a));
+    count2 += PATTERN(L.a*UL.a*U.a + U.a*UR.a*R.a + R.a*DR.a*D.a + D.a*DL.a*L.a);
 
-	if ((count < CD_HUD_DETAILS)  && (count2 < 1.0))
+    count3 += PATTERN(L3.a*L2.a*L.a);
+    count3 += PATTERN(L2.a*L.a*R.a);
+    count3 += PATTERN(L.a*R.a*R2.a);
+    count3 += PATTERN(R.a*R2.a*R3.a);
+
+    count3 += PATTERN(U3.a*U2.a*U.a);
+    count3 += PATTERN(U2.a*U.a*D.a);
+    count3 += PATTERN(U.a*D.a*D2.a);
+    count3 += PATTERN(D.a*D2.a*D3.a);
+
+    if ((count < CD_MITIG_NEIGHBRS)  && (count2 < 1.0))
+        color = oriC;
+    else if ((CD_MITIG_LINES == 1.0) && (count3 < 1.0))
         color = oriC;
 
     float luma_diff = abs(dot(oriC, Y)-dot(color, Y));

dithering/shaders/checkerboard-dedither/linearize.slang

@@ -6,11 +6,15 @@ layout(push_constant) uniform Push
 	vec4 OriginalSize;
 	vec4 OutputSize;
 	uint FrameCount;
-	float InputGamma;
+	float CD_BLEND_OPTION;
+	float UseGamma;
 } params;
 
+#pragma parameter CD_BLEND_OPTION    "CHECKERBOARD-DEDITHER: [ OFF | ON ]" 1.0  0.0 1.0  1.0
+#pragma parameter UseGamma           "    Gamma Slider"                    1.0  0.0 1.0  0.1
 
-#define InputGamma 2.0
+#define UseGamma     params.UseGamma
+#define InputGamma   (UseGamma+1.0)
 
 #define GAMMA_IN(color)     pow(color, vec3(InputGamma, InputGamma, InputGamma))