Impostors: dilate baked textures

1 files changed, 55 insertions, 0 deletions

diff --git a/Scripts/Impostors.cs b/Scripts/Impostors.cs
index 30b06f6..ffd32b4 100644
--- a/Scripts/Impostors.cs
+++ b/Scripts/Impostors.cs
@@ -287,6 +287,56 @@ public class Impostors : MonoBehaviour
     }
   }
 
+  void DilateTexture(Texture2D tex, Texture2D alphaSource, bool preserveAlpha = false, int iterations = 8)
+  {
+    int w = tex.width, h = tex.height;
+    Color[] pixels = tex.GetPixels();
+    Color[] alpha = alphaSource.GetPixels();
+    Color[] origAlpha = preserveAlpha ? (Color[])alpha.Clone() : null;
+    Color[] buffer = (Color[])pixels.Clone();
+
+    int[] dx = { -1, 1, 0, 0 };
+    int[] dy = { 0, 0, -1, 1 };
+
+    for (int iter = 0; iter < iterations; iter++)
+    {
+      for (int y = 0; y < h; y++)
+      {
+        for (int x = 0; x < w; x++)
+        {
+          int i = y * w + x;
+          if (alpha[i].a > 0.01f) continue;
+
+          Color sum = Color.clear;
+          int count = 0;
+          for (int d = 0; d < 4; d++)
+          {
+            int nx = x + dx[d], ny = y + dy[d];
+            if (nx < 0 || nx >= w || ny < 0 || ny >= h) continue;
+            int ni = ny * w + nx;
+            if (alpha[ni].a > 0.01f || (iter > 0 && pixels[ni].a > 0))
+            {
+              sum += pixels[ni];
+              count++;
+            }
+          }
+          if (count > 0)
+          {
+            buffer[i] = sum / count;
+            buffer[i].a = 1;
+          }
+        }
+      }
+      var tmp = pixels; pixels = buffer; buffer = tmp;
+    }
+
+    if (preserveAlpha)
+      for (int i = 0; i < pixels.Length; i++) pixels[i].a = origAlpha[i].a;
+
+    tex.SetPixels(pixels);
+    tex.Apply();
+  }
+
   void SaveAndConfigureTexture(Texture2D atlas, TextureExportSettings settings, string baseName, out string path)
   {
     path = Path.Combine(OutputFolder, $"{baseName}_{settings.suffix}.{(settings.isEXR ? "exr" : "png")}");
@@ -332,6 +382,11 @@ public class Impostors : MonoBehaviour
       (new TextureExportSettings("depth", isEXR: true, mipmaps: false, sRGB: false, filter: FilterMode.Bilinear, uncompressed: true), "_Impostors_Depth_Atlas")
     };
 
+    // Dilate RGB to prevent dark halos from texture filtering
+    DilateTexture(albedoAtlas, albedoAtlas, preserveAlpha: true);
+    DilateTexture(normalAtlas, albedoAtlas);
+    DilateTexture(metallicGlossAtlas, albedoAtlas);
+
     Texture2D[] atlases = { albedoAtlas, normalAtlas, metallicGlossAtlas, depthAtlas };
     string[] paths = new string[exportSettings.Length];
     for (int i = 0; i < exportSettings.Length; i++)