Impostors: fix depth capture

1 files changed, 84 insertions, 25 deletions

diff --git a/Scripts/Impostors.cs b/Scripts/Impostors.cs
index 6d8d67b..ded7e6d 100644
--- a/Scripts/Impostors.cs
+++ b/Scripts/Impostors.cs
@@ -130,29 +130,67 @@ public class Impostors : MonoBehaviour
     SetRenderersEnabled(true);
     if (cameras == null || cameras.Length != gridResolution * gridResolution || cameras[0] == null) CreateCameras();
 
+    // Load depth blit shader
+    Shader depthBlitShader = Shader.Find("Hidden/yum_food/DepthBlit");
+    if (depthBlitShader == null) { Debug.LogError("DepthBlit shader not found"); return; }
+    Material depthBlitMat = new Material(depthBlitShader);
+
     // Render atlas
     int size = cameraResolution * gridResolution;
-    Texture2D atlas = new Texture2D(size, size, TextureFormat.RGBA32, false);
-    RenderTexture rt = RenderTexture.GetTemporary(cameraResolution, cameraResolution, 24);
+    Texture2D colorAtlas = new Texture2D(size, size, TextureFormat.RGBA32, false);
+    Texture2D depthAtlas = new Texture2D(size, size, TextureFormat.RFloat, false);
+
+    // Create RT with depth buffer that can be sampled as texture
+    RenderTextureDescriptor desc = new RenderTextureDescriptor(cameraResolution, cameraResolution, RenderTextureFormat.ARGB32, 24);
+    desc.sRGB = true;
+    RenderTexture colorRT = RenderTexture.GetTemporary(desc);
+
+    // Separate depth texture
+    RenderTextureDescriptor depthDesc = new RenderTextureDescriptor(cameraResolution, cameraResolution, RenderTextureFormat.Depth, 24);
+    RenderTexture depthOnlyRT = RenderTexture.GetTemporary(depthDesc);
+
+    // Output for linearized depth
+    RenderTexture linearDepthRT = RenderTexture.GetTemporary(cameraResolution, cameraResolution, 0, RenderTextureFormat.RFloat);
 
     int idx = 0;
     for (int y = 0; y < gridResolution; y++)
     {
       for (int x = 0; x < gridResolution; x++)
       {
-        cameras[idx++].targetTexture = rt;
-        cameras[idx - 1].Render();
-        RenderTexture.active = rt;
-        Texture2D temp = new Texture2D(cameraResolution, cameraResolution);
-        temp.ReadPixels(new Rect(0, 0, cameraResolution, cameraResolution), 0, 0);
-        temp.Apply();
-        atlas.SetPixels(x * cameraResolution, y * cameraResolution, cameraResolution, cameraResolution, temp.GetPixels());
-        DestroyImmediate(temp);
+        Camera cam = cameras[idx++];
+
+        // Render to color + depth buffers simultaneously
+        cam.SetTargetBuffers(colorRT.colorBuffer, depthOnlyRT.depthBuffer);
+        cam.Render();
+
+        // Read color
+        RenderTexture.active = colorRT;
+        Texture2D colorTemp = new Texture2D(cameraResolution, cameraResolution);
+        colorTemp.ReadPixels(new Rect(0, 0, cameraResolution, cameraResolution), 0, 0);
+        colorTemp.Apply();
+        colorAtlas.SetPixels(x * cameraResolution, y * cameraResolution, cameraResolution, cameraResolution, colorTemp.GetPixels());
+        DestroyImmediate(colorTemp);
+
+        // Blit depth buffer through linearization shader
+        depthBlitMat.SetTexture("_DepthTex", depthOnlyRT);
+        Graphics.Blit(null, linearDepthRT, depthBlitMat);
+
+        // Read linearized depth
+        RenderTexture.active = linearDepthRT;
+        Texture2D depthTemp = new Texture2D(cameraResolution, cameraResolution, TextureFormat.RFloat, false);
+        depthTemp.ReadPixels(new Rect(0, 0, cameraResolution, cameraResolution), 0, 0);
+        depthTemp.Apply();
+        depthAtlas.SetPixels(x * cameraResolution, y * cameraResolution, cameraResolution, cameraResolution, depthTemp.GetPixels());
+        DestroyImmediate(depthTemp);
       }
     }
-    atlas.Apply();
+    colorAtlas.Apply();
+    depthAtlas.Apply();
     RenderTexture.active = null;
-    RenderTexture.ReleaseTemporary(rt);
+    RenderTexture.ReleaseTemporary(colorRT);
+    RenderTexture.ReleaseTemporary(depthOnlyRT);
+    RenderTexture.ReleaseTemporary(linearDepthRT);
+    DestroyImmediate(depthBlitMat);
 
     // Save
     if (!AssetDatabase.IsValidFolder(OutputFolder))
@@ -163,24 +201,43 @@ public class Impostors : MonoBehaviour
     }
 
     string name = gameObject.name.Replace(" ", "_");
-    string path = Path.Combine(OutputFolder, $"{name}_atlas.png");
-    File.WriteAllBytes(Path.Combine(Application.dataPath, "..", path), atlas.EncodeToPNG());
-    DestroyImmediate(atlas);
+    string colorPath = Path.Combine(OutputFolder, $"{name}_atlas.png");
+    string depthPath = Path.Combine(OutputFolder, $"{name}_depth.exr");
+
+    File.WriteAllBytes(Path.Combine(Application.dataPath, "..", colorPath), colorAtlas.EncodeToPNG());
+    File.WriteAllBytes(Path.Combine(Application.dataPath, "..", depthPath), depthAtlas.EncodeToEXR(Texture2D.EXRFlags.OutputAsFloat));
+    DestroyImmediate(colorAtlas);
+    DestroyImmediate(depthAtlas);
 
     AssetDatabase.Refresh();
-    TextureImporter importer = AssetImporter.GetAtPath(path) as TextureImporter;
-    if (importer != null)
+
+    // Configure color atlas importer
+    TextureImporter colorImporter = AssetImporter.GetAtPath(colorPath) as TextureImporter;
+    if (colorImporter != null)
+    {
+      colorImporter.mipmapEnabled = true;
+      colorImporter.alphaIsTransparency = true;
+      colorImporter.wrapMode = TextureWrapMode.Clamp;
+      colorImporter.filterMode = FilterMode.Trilinear;
+      colorImporter.SaveAndReimport();
+    }
+
+    // Configure depth atlas importer
+    TextureImporter depthImporter = AssetImporter.GetAtPath(depthPath) as TextureImporter;
+    if (depthImporter != null)
     {
-      importer.mipmapEnabled = true;
-      importer.alphaIsTransparency = true;
-      importer.wrapMode = TextureWrapMode.Clamp;
-      importer.filterMode = FilterMode.Trilinear;
-      importer.SaveAndReimport();
+      depthImporter.mipmapEnabled = false;
+      depthImporter.sRGBTexture = false;  // Linear data
+      depthImporter.wrapMode = TextureWrapMode.Clamp;
+      depthImporter.filterMode = FilterMode.Bilinear;
+      depthImporter.textureCompression = TextureImporterCompression.Uncompressed;
+      depthImporter.SaveAndReimport();
     }
 
     // Create impostor
-    Texture2D tex = AssetDatabase.LoadAssetAtPath<Texture2D>(path);
-    if (tex != null)
+    Texture2D colorTex = AssetDatabase.LoadAssetAtPath<Texture2D>(colorPath);
+    Texture2D depthTex = AssetDatabase.LoadAssetAtPath<Texture2D>(depthPath);
+    if (colorTex != null)
     {
       DestroyExistingImpostor();
 
@@ -188,8 +245,10 @@ public class Impostors : MonoBehaviour
       if (shader == null) { Debug.LogError("Shader not found"); return; }
 
       impostorMaterial = new Material(shader);
-      impostorMaterial.SetTexture("_ImpostorAtlas", tex);
+      impostorMaterial.SetTexture("_ImpostorAtlas", colorTex);
+      impostorMaterial.SetTexture("_ImpostorDepthAtlas", depthTex);
       impostorMaterial.SetInt("_GridResolution", gridResolution);
+      impostorMaterial.SetFloat("_SphereRadius", sphere_radius_);
       AssetDatabase.CreateAsset(impostorMaterial, Path.Combine(OutputFolder, $"{name}_mat.mat"));
 
       impostorObject = GameObject.CreatePrimitive(PrimitiveType.Quad);