From 4ea09b0b8b029480a9ea313db0dc4af23fc4a2a8 Mon Sep 17 00:00:00 2001
From: Kelsi <kelsihates2fa@gmail.com>
Date: Tue, 5 May 2026 11:08:40 -0700
Subject: [PATCH] feat(editor): alpha map export as individual 64x64 grayscale
 PNGs

---
 tools/editor/wowee_terrain.cpp | 23 +++++++++++++++++++++++
 tools/editor/wowee_terrain.hpp |  4 ++++
 2 files changed, 27 insertions(+)

diff --git a/tools/editor/wowee_terrain.cpp b/tools/editor/wowee_terrain.cpp
index eafe82fb..9784630f 100644
--- a/tools/editor/wowee_terrain.cpp
+++ b/tools/editor/wowee_terrain.cpp
@@ -121,6 +121,29 @@ bool WoweeTerrain::exportNormalMap(const pipeline::ADTTerrain& terrain,
     return true;
 }
 
+int WoweeTerrain::exportAlphaMaps(const pipeline::ADTTerrain& terrain,
+                                    const std::string& outputDir) {
+    namespace fs = std::filesystem;
+    fs::create_directories(outputDir);
+    int exported = 0;
+
+    for (int ci = 0; ci < 256; ci++) {
+        const auto& chunk = terrain.chunks[ci];
+        for (size_t li = 1; li < chunk.layers.size(); li++) {
+            if (!chunk.layers[li].useAlpha()) continue;
+            size_t off = chunk.layers[li].offsetMCAL;
+            if (off + 4096 > chunk.alphaMap.size()) continue;
+
+            std::string path = outputDir + "/chunk_" + std::to_string(ci) +
+                               "_layer_" + std::to_string(li) + ".png";
+            stbi_write_png(path.c_str(), 64, 64, 1,
+                           chunk.alphaMap.data() + off, 64);
+            exported++;
+        }
+    }
+    return exported;
+}
+
 bool WoweeTerrain::importOpen(const std::string& basePath, pipeline::ADTTerrain& terrain) {
     std::string hmPath = basePath + ".whm";
     std::ifstream f(hmPath, std::ios::binary);
diff --git a/tools/editor/wowee_terrain.hpp b/tools/editor/wowee_terrain.hpp
index fa459af4..825a4982 100644
--- a/tools/editor/wowee_terrain.hpp
+++ b/tools/editor/wowee_terrain.hpp
@@ -18,6 +18,10 @@ public:
     static bool exportNormalMap(const pipeline::ADTTerrain& terrain,
                                 const std::string& path);
 
+    // Export alpha maps as individual 64x64 grayscale PNGs per chunk layer
+    static int exportAlphaMaps(const pipeline::ADTTerrain& terrain,
+                                const std::string& outputDir);
+
     // Import terrain from open format back to ADTTerrain
     static bool importOpen(const std::string& basePath, pipeline::ADTTerrain& terrain);
 };