fix: SDXL ControlNet (diffusers naming + graph size) (#1752)

src/model/diffusion/control.hpp

@@ -5,7 +5,8 @@
 #include "model_loader.h"
 #include "model_manager.h"
 
-#define CONTROL_NET_GRAPH_SIZE 1536
+// Match main UNet's MAX_GRAPH_SIZE so SDXL ControlNet (transformer_depth={1,2,10}) fits.
+#define CONTROL_NET_GRAPH_SIZE MAX_GRAPH_SIZE
 
 /*
     =================================== ControlNet ===================================

src/name_conversion.cpp

@@ -736,6 +736,62 @@ std::string convert_diffusers_dit_to_original_krea2(std::string name) {
     return name;
 }
 
+// Convert a diffusers-format ControlNet tensor name to the original (LDM/lllyasviel) layout
+// declared by ControlNetBlock. Reuses the UNet down/mid conversion for the shared encoder
+// (down_blocks, mid_block, time_embedding, add_embedding, conv_in) and adds the ControlNet-only
+// mappings: input_hint_block, zero_convs, middle_block_out.
+std::string convert_diffusers_controlnet_to_original_sdxl(std::string name) {
+    name = convert_diffusers_unet_to_original_sdxl(std::move(name));
+
+    static const std::vector<std::pair<std::string, std::string>> prefix_map = {
+        {"controlnet_cond_embedding.conv_in.", "input_hint_block.0."},
+        {"controlnet_cond_embedding.blocks.0.", "input_hint_block.2."},
+        {"controlnet_cond_embedding.blocks.1.", "input_hint_block.4."},
+        {"controlnet_cond_embedding.blocks.2.", "input_hint_block.6."},
+        {"controlnet_cond_embedding.blocks.3.", "input_hint_block.8."},
+        {"controlnet_cond_embedding.blocks.4.", "input_hint_block.10."},
+        {"controlnet_cond_embedding.blocks.5.", "input_hint_block.12."},
+        {"controlnet_cond_embedding.conv_out.", "input_hint_block.14."},
+        {"controlnet_mid_block.", "middle_block_out.0."},
+    };
+    for (const auto& p : prefix_map) {
+        if (starts_with(name, p.first)) {
+            return p.second + name.substr(p.first.size());
+        }
+    }
+
+    static const std::string controlnet_down_prefix = "controlnet_down_blocks.";
+    if (starts_with(name, controlnet_down_prefix)) {
+        size_t rest_start = controlnet_down_prefix.size();
+        size_t dot        = name.find('.', rest_start);
+        if (dot != std::string::npos) {
+            std::string idx = name.substr(rest_start, dot - rest_start);
+            return "zero_convs." + idx + ".0" + name.substr(dot);
+        }
+    }
+
+    return name;
+}
+
+static bool is_diffusers_controlnet_name(const std::string& name) {
+    static const std::vector<std::string> heads = {
+        "controlnet_cond_embedding.",
+        "controlnet_down_blocks.",
+        "controlnet_mid_block.",
+        "down_blocks.",
+        "mid_block.",
+        "time_embedding.",
+        "add_embedding.",
+        "conv_in.",
+    };
+    for (const auto& h : heads) {
+        if (starts_with(name, h)) {
+            return true;
+        }
+    }
+    return false;
+}
+
 std::string convert_diffusion_model_name(std::string name, std::string prefix, SDVersion version) {
     if (sd_version_is_sd1(version) || sd_version_is_sd2(version)) {
         name = convert_diffusers_unet_to_original_sd1(name);
@@ -1338,6 +1394,9 @@ std::string convert_tensor_name(std::string name, SDVersion version) {
                 name = name.substr(pos + 1);
             }
         }
+        if (sd_version_is_sdxl(version) && is_diffusers_controlnet_name(name)) {
+            name = convert_diffusers_controlnet_to_original_sdxl(name);
+        }
     }
 
     if (is_lora) {