[Core] Dynamic image size support for VLMs (#5276)

Signed-off-by: Xiaowei Jiang <xwjiang2010@gmail.com>
Co-authored-by: Xiaowei Jiang <xwjiang2010@gmail.com>
Co-authored-by: ywang96 <ywang@roblox.com>
Co-authored-by: xwjiang2010 <87673679+xwjiang2010@users.noreply.github.com>
Co-authored-by: Roger Wang <136131678+ywang96@users.noreply.github.com>

docs/source/dev/multimodal/multimodal_index.rst

@@ -1,3 +1,5 @@
+.. _multi_modality:
+
 Multi-Modality
 ==============
 
@@ -8,12 +10,18 @@ vLLM provides experimental support for multi-modal models through the :mod:`vllm
 :class:`vllm.inputs.PromptStrictInputs` accepts an additional attribute ``multi_modal_data``
 which allows you to pass in multi-modal input alongside text and token prompts.
 
-By default, vLLM models do not support multi-modal inputs. To enable multi-modal support for a model,
-you must decorate the model class with :meth:`InputRegistry.register_dummy_data <vllm.inputs.registry.InputRegistry.register_dummy_data>`,
-as well as :meth:`MULTIMODAL_REGISTRY.register_input_mapper <MultiModalRegistry.register_input_mapper>` for each modality type to support.
+By default, vLLM models do not support multi-modal inputs. To enable multi-modal support for a model, please follow :ref:`the guide for adding a new multimodal model. <adding_a_new_multimodal_model>`.
 
 # TODO: Add more instructions on how to do that once embeddings is in.
 
+Guides
+++++++
+
+.. toctree::
+   :maxdepth: 1
+
+   adding_multimodal_model
+
 Module Contents
 +++++++++++++++
 
@@ -35,6 +43,10 @@ Base Classes
     :members:
     :show-inheritance:
 
+.. autoclass:: vllm.multimodal.MultiModalInputs
+    :members:
+    :show-inheritance:
+
 .. autoclass:: vllm.multimodal.MultiModalPlugin
     :members:
     :show-inheritance: