[diffusion] feat: make QwenImageLayered resolution configurable (#20044)

python/sglang/multimodal_gen/configs/pipeline_configs/base.py

@@ -436,6 +436,13 @@ class PipelineConfig:
             default=PipelineConfig.flow_shift,
             help="Flow shift parameter",
         )
+        parser.add_argument(
+            f"--{prefix_with_dot}resolution",
+            type=int,
+            dest=f"{prefix_with_dot.replace('-', '_')}resolution",
+            default=None,
+            help="Override the selected pipeline config's resolution setting. Only applies to pipelines that define a resolution field.",
+        )
 
         # DiT configuration
         parser.add_argument(

python/sglang/multimodal_gen/configs/pipeline_configs/qwen_image.py

@@ -500,7 +500,7 @@ class QwenImageEditPlus_2511_PipelineConfig(QwenImageEditPlusPipelineConfig):
 
 @dataclass
 class QwenImageLayeredPipelineConfig(QwenImageEditPipelineConfig):
-    resolution: int = 640  # TODO: allow user to set resolution
+    resolution: int = 640
     vae_precision: str = "bf16"
 
     def _prepare_edit_cond_kwargs(

python/sglang/multimodal_gen/runtime/pipelines_core/stages/model_specific_stages/qwen_image_layered.py

@@ -422,7 +422,7 @@ the image\n<|vision_start|><|image_pad|><|vision_end|><|im_end|>\n<|im_start|>as
         image = load_image(batch.image_path[0])
         image = image.convert("RGBA")
         image_size = image.size
-        resolution = 640  # TODO: support user-specified resolution
+        resolution = server_args.pipeline_config.resolution
         calculated_width, calculated_height = calculate_dimensions(
             resolution * resolution, image_size[0] / image_size[1]
         )

python/sglang/multimodal_gen/test/unit/test_server_args_unit.py

@@ -1,8 +1,11 @@
 import os
+import sys
 import unittest
+from unittest.mock import patch
 
 from sglang.multimodal_gen.registry import _get_config_info
 from sglang.multimodal_gen.runtime.server_args import ServerArgs
+from sglang.multimodal_gen.utils import FlexibleArgumentParser
 
 
 class TestServerArgsPathExpansion(unittest.TestCase):
@@ -46,5 +49,26 @@ class TestModelIdResolution(unittest.TestCase):
             _get_config_info("/data/no-such-model", model_id="NonExistentModelXYZ")
 
 
+class TestPipelineResolutionCliOverride(unittest.TestCase):
+    def setUp(self):
+        _get_config_info.cache_clear()
+
+    def test_resolution_flag_overrides_qwen_image_layered_pipeline_config(self):
+        parser = FlexibleArgumentParser()
+        ServerArgs.add_cli_args(parser)
+        argv = [
+            "--model-path",
+            "Qwen/Qwen-Image-Layered",
+            "--resolution",
+            "768",
+        ]
+
+        with patch.object(sys, "argv", ["sglang"] + argv):
+            args, unknown_args = parser.parse_known_args(argv)
+            server_args = ServerArgs.from_cli_args(args, unknown_args)
+
+        self.assertEqual(server_args.pipeline_config.resolution, 768)
+
+
 if __name__ == "__main__":
     unittest.main()