Improve soft-edges handling.

Swordfish90 · Jul 13, 2024 · c3014fb · c3014fb
1 parent 0cac511
commit c3014fb
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Showing 4 changed files with 17 additions and 13 deletions.
diff --git a/src/shaders/cut2/cut2_pass_0.frag.glsl b/src/shaders/cut2/cut2_pass_0.frag.glsl
@@ -79,9 +79,10 @@ lowp int findPattern(lowp vec4 values, lowp vec2 saddleAdjustments) {
     max(patternContrasts.z, patternContrasts.w)
   );
 
-  bvec4 isMax = greaterThanEqual(patternContrasts, vec4(maxContrast));
+  bvec4 isMax = greaterThanEqual(patternContrasts, vec4(maxContrast - EPSILON));
+  bool isSaddle = all(isMax);
 
-  if (maxContrast < EDGE_MIN_VALUE) {
+  if (maxContrast < EDGE_MIN_VALUE || isSaddle) {
     return 0;
   } else if (isMax.x) {
     return 1;
@@ -98,8 +99,8 @@ lowp int findPattern(lowp vec4 values, lowp vec2 saddleAdjustments) {
 
 lowp float softEdgeWeight(lowp float a, lowp float b, lowp float c, lowp float d) {
   lowp float result = 0.0;
-  result += clamp(1.0 - 2.0 * abs((max(abs(b - c), abs(c - d))) / (abs(b - d) + EPSILON) - 0.5), 0.0, 1.0);
-  result -= clamp(1.0 - 2.0 * abs((max(abs(a - b), abs(b - c))) / (abs(a - c) + EPSILON) - 0.5), 0.0, 1.0);
+  result += clamp(abs((2.0 * b - (a + c))) / abs(a - c), 0.0, 1.0);
+  result -= clamp(abs((2.0 * c - (d + b))) / abs(b - d), 0.0, 1.0);
   return clamp(result, -1.0, 1.0);
 }
 
@@ -164,12 +165,13 @@ void main() {
   );
 
 #if SOFT_EDGES_SHARPENING
-  lowp vec4 softEdges = SOFT_EDGES_SHARPENING_AMOUNT * vec4(
+  lowp vec4 softEdges = vec4(
     softEdgeWeight(l04, l05, l06, l07),
     softEdgeWeight(l02, l06, l10, l14),
     softEdgeWeight(l08, l09, l10, l11),
     softEdgeWeight(l01, l05, l09, l13)
   );
+  softEdges = clamp(softEdges, vec4(-SOFT_EDGES_SHARPENING_AMOUNT), vec4(SOFT_EDGES_SHARPENING_AMOUNT));
 
   edges = clamp(edges + softEdges, min(edges, softEdges), max(edges, softEdges));
 #endif

diff --git a/src/shaders/cut3/cut3_pass_0.frag.glsl b/src/shaders/cut3/cut3_pass_0.frag.glsl
@@ -79,9 +79,10 @@ lowp int findPattern(lowp vec4 values, lowp vec2 saddleAdjustments) {
     max(patternContrasts.z, patternContrasts.w)
   );
 
-  bvec4 isMax = greaterThanEqual(patternContrasts, vec4(maxContrast));
+  bvec4 isMax = greaterThanEqual(patternContrasts, vec4(maxContrast - EPSILON));
+  bool isSaddle = all(isMax);
 
-  if (maxContrast < EDGE_MIN_VALUE) {
+  if (maxContrast < EDGE_MIN_VALUE || isSaddle) {
     return 0;
   } else if (isMax.x) {
     return 1;
@@ -98,8 +99,8 @@ lowp int findPattern(lowp vec4 values, lowp vec2 saddleAdjustments) {
 
 lowp float softEdgeWeight(lowp float a, lowp float b, lowp float c, lowp float d) {
   lowp float result = 0.0;
-  result += clamp(1.0 - 2.0 * abs((max(abs(b - c), abs(c - d))) / (abs(b - d) + EPSILON) - 0.5), 0.0, 1.0);
-  result -= clamp(1.0 - 2.0 * abs((max(abs(a - b), abs(b - c))) / (abs(a - c) + EPSILON) - 0.5), 0.0, 1.0);
+  result += clamp(abs((2.0 * b - (a + c))) / abs(a - c), 0.0, 1.0);
+  result -= clamp(abs((2.0 * c - (d + b))) / abs(b - d), 0.0, 1.0);
   return clamp(result, -1.0, 1.0);
 }
 

diff --git a/src/shaders/cut3/cut3_pass_1.frag.glsl b/src/shaders/cut3/cut3_pass_1.frag.glsl
@@ -27,8 +27,8 @@ precision lowp float;
 
 #define EPSILON 0.02
 
-const float STEP = 0.5 / float(MAX_SEARCH_DISTANCE);
-const float HSTEP = (STEP * 0.5);
+const lowp float STEP = 0.5 / float(MAX_SEARCH_DISTANCE);
+const lowp float HSTEP = (STEP * 0.5);
 
 uniform lowp sampler2D previousPass;
 
@@ -173,10 +173,11 @@ void main() {
   );
 
 #if SOFT_EDGES_SHARPENING
-  lowp vec4 softEdges = 2.0 * SOFT_EDGES_SHARPENING_AMOUNT * vec4(
+  lowp vec4 softEdges = 2.0 * vec4(
     quickUnpackFloats2(previousPassPixel.y + 0.001953125) - vec2(0.5),
     quickUnpackFloats2(previousPassPixel.z + 0.001953125) - vec2(0.5)
   );
+  softEdges = clamp(softEdges, vec4(-SOFT_EDGES_SHARPENING_AMOUNT), vec4(SOFT_EDGES_SHARPENING_AMOUNT));
 
   edges = clamp(edges + softEdges, min(edges, softEdges), max(edges, softEdges));
 #endif

diff --git a/src/shaders/cut3/cut3_pass_2.frag.glsl b/src/shaders/cut3/cut3_pass_2.frag.glsl
@@ -143,7 +143,7 @@ ShapeWeights triangleWeights(lowp vec2 pxCoords, lowp vec2 edgeWeights) {
   ShapeWeights result;
   lowp float m = edgeWeights.x;
   lowp float n = edgeWeights.y;
-  lowp float a = (n * m + pxCoords.y * (1.0 - m - n)) / (n * m + pxCoords.x * (1.0 - m - n));
+  lowp float a = (n * m + pxCoords.y * (1.0 - m - n)) / (n * m + pxCoords.x * (1.0 - m - n) + EPSILON);
   lowp vec2 projections = vec2((pxCoords.y -a * pxCoords.x), (1.0 - pxCoords.y) / a + pxCoords.x);
   result.weights = vec3(projections.x, projections.y, pxCoords.x / (projections.y + EPSILON));
   result.midPoints = vec3(m, n, 0.5);