Impostors: add parallax correction

1 files changed, 61 insertions, 4 deletions

diff --git a/Scripts/Impostors.cs b/Scripts/Impostors.cs
index ffd32b4..46e6cd1 100644
--- a/Scripts/Impostors.cs
+++ b/Scripts/Impostors.cs
@@ -26,7 +26,7 @@ public class Impostors : MonoBehaviour
   private Material impostorMaterial;
 
   public bool HasImpostor => impostorObject != null;
-  private float Radius => sphere_radius_ * transform.lossyScale.x;
+  private float Radius => sphere_radius_ * Mathf.Max(transform.lossyScale.x, transform.lossyScale.y, transform.lossyScale.z);
   private const string OutputFolder = "Assets/yum_food/3ner/Impostor_Generated";
 
   void OnEnable() => Camera.onPreRender += UpdateMainCameraPos;
@@ -35,7 +35,7 @@ public class Impostors : MonoBehaviour
   static void UpdateMainCameraPos(Camera cam)
   {
     if (cam.cameraType == CameraType.Game || cam.cameraType == CameraType.SceneView)
-      Shader.SetGlobalVector("_ImpostorMainCameraPos", cam.transform.position);
+      Shader.SetGlobalVector("_Impostors_Main_Camera_Pos", cam.transform.position);
   }
 
   void OnDrawGizmos()
@@ -105,9 +105,9 @@ public class Impostors : MonoBehaviour
 
         Camera cam = camObj.AddComponent<Camera>();
         cam.orthographic = true;
-        cam.orthographicSize = sphere_radius_;
+        cam.orthographicSize = Radius;
         cam.nearClipPlane = nearClippingDistance;
-        cam.farClipPlane = sphere_radius_ * 2f + nearClippingDistance;
+        cam.farClipPlane = Radius * 2f + nearClippingDistance;
         cam.cullingMask = cullingMask;
         cam.clearFlags = renderSkybox ? CameraClearFlags.Skybox : CameraClearFlags.SolidColor;
         cam.backgroundColor = Color.clear;
@@ -337,6 +337,61 @@ public class Impostors : MonoBehaviour
     tex.Apply();
   }
 
+  void DilateDepthTexture(Texture2D depthTex, Texture2D alphaSource, int iterations = 8)
+  {
+    int w = depthTex.width, h = depthTex.height;
+    Color[] depth = depthTex.GetPixels();
+    Color[] mask = alphaSource.GetPixels();
+
+    bool[] filled = new bool[depth.Length];
+    for (int i = 0; i < depth.Length; i++)
+      filled[i] = mask[i].a > 0.01f;
+
+    Color[] buffer = (Color[])depth.Clone();
+    bool[] filledNext = new bool[filled.Length];
+
+    int[] dx = { -1, 1, 0, 0 };
+    int[] dy = { 0, 0, -1, 1 };
+
+    for (int iter = 0; iter < iterations; iter++)
+    {
+      System.Array.Copy(filled, filledNext, filled.Length);
+
+      for (int y = 0; y < h; y++)
+      {
+        for (int x = 0; x < w; x++)
+        {
+          int i = y * w + x;
+          if (filled[i]) continue;
+
+          float sum = 0f;
+          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 (!filled[ni]) continue;
+            sum += depth[ni].r;
+            count++;
+          }
+
+          if (count > 0)
+          {
+            buffer[i].r = sum / count;
+            filledNext[i] = true;
+          }
+        }
+      }
+
+      var tmpFilled = filled; filled = filledNext; filledNext = tmpFilled;
+      var tmpDepth = depth; depth = buffer; buffer = tmpDepth;
+    }
+
+    depthTex.SetPixels(depth);
+    depthTex.Apply();
+  }
+
   void SaveAndConfigureTexture(Texture2D atlas, TextureExportSettings settings, string baseName, out string path)
   {
     path = Path.Combine(OutputFolder, $"{baseName}_{settings.suffix}.{(settings.isEXR ? "exr" : "png")}");
@@ -386,6 +441,7 @@ public class Impostors : MonoBehaviour
     DilateTexture(albedoAtlas, albedoAtlas, preserveAlpha: true);
     DilateTexture(normalAtlas, albedoAtlas);
     DilateTexture(metallicGlossAtlas, albedoAtlas);
+    DilateDepthTexture(depthAtlas, albedoAtlas);
 
     Texture2D[] atlases = { albedoAtlas, normalAtlas, metallicGlossAtlas, depthAtlas };
     string[] paths = new string[exportSettings.Length];
@@ -426,6 +482,7 @@ public class Impostors : MonoBehaviour
       impostorMaterial.SetInt("_Impostors_Grid_Resolution", gridResolution);
       impostorMaterial.SetFloat("_Impostors_Sphere_Radius", sphere_radius_);
       impostorMaterial.SetFloat("_Impostors_Enabled", 1);
+      impostorMaterial.SetFloat("_Impostors_Parallax", 1);
       impostorMaterial.SetFloat("_Cull", (float)UnityEngine.Rendering.CullMode.Front);
       AssetDatabase.CreateAsset(impostorMaterial, Path.Combine(OutputFolder, $"{baseName}_mat.mat"));