Added reading texture map input from file so we can give custom names to the entries.

private/texture_packer/packer.cpp

@@ -14,12 +14,13 @@
 #define STBIW_ASSERT(x) MIJIN_ASSERT(x, #x)
 #define STB_IMAGE_WRITE_IMPLEMENTATION
 #include <stb_image_write.h>
+#include <mijin/util/string.hpp>
 #undef STB_IMAGE_WRITE_IMPLEMENTATION
 #undef STBIW_ASSERT
 
 namespace sdl_gpu_test
 {
-void Packer::addImage(const fs::path& path)
+void Packer::addImage(std::string name, const fs::path& path)
 {
     int width = 0;
     int height = 0;
@@ -37,13 +38,35 @@ void Packer::addImage(const fs::path& path)
     }
 
     mImages.push_back({
-        .name = path.generic_string(),
+        .name = std::move(name),
         .data = std::unique_ptr<Pixel[], FreeDeleter>(reinterpret_cast<Pixel*>(pixels)),
         .width = static_cast<unsigned>(width),
         .height = static_cast<unsigned>(height)
     });
 }
 
+void Packer::addImageList(const fs::path& path)
+{
+    mijin::FileStream stream;
+    mijin::throwOnError(stream.open(path.generic_string(), mijin::FileOpenMode::READ));
+    while (!stream.isAtEnd())
+    {
+        std::string line;
+        mijin::throwOnError(stream.readLine(line));
+        if (line.empty())
+        {
+            continue;
+        }
+        const auto [name, file] = mijin::splitFixed<2>(line, " ");
+        if (file.empty())
+        {
+            throw std::runtime_error("Invalid image list format, missing file name.");
+        }
+        addImage(std::string(name), path.parent_path() / file);
+    }
+}
+
+
 void Packer::pack(const fs::path& outputPath)
 {
     static constexpr bool allowFlip = false; // TODO: this could work?