Simplify part of the code, increase samples.

Author: klaussilveira

base/glprogs/interaction.glprog

@@ -119,7 +119,6 @@ glprog interaction
         uniform sampler2D lightImage;
         uniform sampler2D diffuseImage;
         uniform sampler2D specularImage;
-        uniform sampler2D specularTableImage;
         uniform sampler2D shadowMaps[6];
         uniform float maxPOMDistance; // Add this uniform to control POM distance
 
@@ -161,8 +160,7 @@ glprog interaction
                 vec2(-0.24188840, 0.99706507),
                 vec2(-0.81409955, 0.91437590),
                 vec2(0.19984126, 0.78641367),
-                vec2(0.14383161, -0.14100790)
-            );
+                vec2(0.14383161, -0.14100790));
 
             // Generate a random rotation based on screen position to reduce banding
             float screenSize = 1024.0;
@@ -176,15 +174,14 @@ glprog interaction
 
             float factor = 0.0;
 
-			// Could increase this to 16 or 32 for better quality
-            int samples = 8;
+            // Could increase this to 16 or 32 for better quality
+            int samples = 16;
 
             for (int i = 0; i < samples; i++) {
                 // Rotate the sample position
                 vec2 rotatedOffset = vec2(
                     poissonDisk[i].x * c - poissonDisk[i].y * s,
-                    poissonDisk[i].x * s + poissonDisk[i].y * c
-                );
+                    poissonDisk[i].x * s + poissonDisk[i].y * c);
 
                 // Apply scaled offset
                 vec2 sampleCoord = coord.xy + rotatedOffset * filterSize;
@@ -211,25 +208,30 @@ glprog interaction
             float viewDistance = length(lightVector);
             float pomQualityFactor = clamp(1.0 - viewDistance / maxPOMDistance, 0.0, 1.0);
 
+            // Only perform POM if the quality factor is significant
             if (pomQualityFactor > 0.01) {
-                // Only do POM if we're close enough
-                float numLayers = mix(8.0, 32.0, pomQualityFactor); // Fewer layers for distant objects
-                float layerHeight = 0.01 * pomQualityFactor;        // Less height effect for distant objects
+                // Fewer layers for distant objects
+                float numLayers = mix(5.0, 16.0, pomQualityFactor);
+                // Less height effect for distant objects
+                float layerHeight = 0.01 * pomQualityFactor;
 
                 // Initialize parallax mapping
                 float layerDepth = 1.0 / numLayers;
-                vec2 P = V.xy * layerHeight / max(V.z, 0.05); // Prevent division by near-zero
+                // Prevent division by near-zero, use a small epsilon
+                vec2 P = V.xy * layerHeight / max(V.z, 0.05);
                 float currentLayerDepth = 0.0;
                 vec2 deltaTexCoords = P / numLayers;
 
-                // Binary search refinement instead of linear search
-                // First do a coarse linear search
-                float numSearches = 8.0; // Fewer iterations for better performance
-                for (int i = 0; i < int(numSearches); i++) {
-                    float height = normalize(texture2D(bumpImage, bumpedST).xyz * 2.0 - 1.0).z;
+                int numSearches = int(mix(4.0, 8.0, pomQualityFactor));
+                for (int i = 0; i < numSearches; i++) {
+                    // Sample height from the normal map's alpha/blue channel (assuming height is stored there)
+                    // Or derive from normal length if appropriate for your encoding
+                    float height = texture(bumpImage, bumpedST).b;
+
                     if (currentLayerDepth >= height) {
                         break;
                     }
+
                     bumpedST -= deltaTexCoords;
                     diffuseST -= deltaTexCoords;
                     specularST -= deltaTexCoords;
@@ -243,28 +245,30 @@ glprog interaction
                     vec2 prevSpecular = specularST + deltaTexCoords;
 
                     // Binary search to refine the depth
-                    for (int i = 0; i < 4; i++) { // Just a few iterations
+                    for (int i = 0; i < 4; i++) {
                         deltaTexCoords *= 0.5;
                         currentLayerDepth -= layerDepth * 0.5;
 
-                        float height = normalize(texture2D(bumpImage, bumpedST).xyz * 2.0 - 1.0).z;
+                        float height = texture(bumpImage, bumpedST).b;
 
+                        // Check if current depth is below or above the surface
                         if (currentLayerDepth > height) {
-                            bumpedST -= deltaTexCoords;
-                            diffuseST -= deltaTexCoords;
-                            specularST -= deltaTexCoords;
-                            currentLayerDepth += layerDepth * 0.5;
-                        } else {
                             bumpedST += deltaTexCoords;
                             diffuseST += deltaTexCoords;
                             specularST += deltaTexCoords;
+                            currentLayerDepth += layerDepth * 0.5;
+                        } else {
+                            bumpedST -= deltaTexCoords;
+                            diffuseST -= deltaTexCoords;
+                            specularST -= deltaTexCoords;
                             currentLayerDepth -= layerDepth * 0.5;
                         }
+                        layerDepth *= 0.5;
                     }
                 }
             }
 
-            // Sample the bump map and adjust range to [-1, 1]
+            // Sample the bump map *once* after POM and adjust range to [-1, 1]
             vec3 N = normalize(texture(bumpImage, bumpedST).xyz * 2.0 - 1.0);
 
             // Sample the light vector and normalize it