Clarify transform data ordering in RenderingServer.multimesh_set_buffer

Author: biswas08433

doc/classes/RenderingServer.xml

@@ -2639,6 +2639,9 @@
 				  - Position + Custom data: 16 floats (12 floats for Transform3D, 4 floats of custom data)
 				  - Position + Vertex color + Custom data: 20 floats (12 floats for Transform3D, 4 floats for Color, 4 floats of custom data)
 				[/codeblock]
+				Instance transforms are in row-major order. Specifically:
+				- For [Transform2D] the float-order is: [code](x.x, y.x, padding_float, origin.x, x.y, y.y, padding_float, origin.y)[/code].
+				- For [Transform3D] the float-order is: [code](basis.x.x, basis.y.x, basis.z.x, origin.x, basis.x.y, basis.y.y, basis.z.y, origin.y, basis.x.z, basis.y.z, basis.z.z, origin.z)[/code].
 			</description>
 		</method>
 		<method name="multimesh_set_buffer_interpolated">