manual/render/shader_nodes/shader/index.rst

@@ -16,6 +16,7 @@
    hair.rst
    holdout.rst
    mix.rst
+   metallic.rst
    principled.rst
    hair_principled.rst
    volume_principled.rst

manual/render/shader_nodes/shader/metallic.rst

@@ -0,0 +1,153 @@
+.. _bpy.types.ShaderNodeBsdfMetallic:
+
+*************
+Metallic BSDF
+*************
+
+.. figure:: /images/node-types_ShaderNodeBsdfMetallic.webp
+   :align: right
+   :alt: Metallic BSDF node.
+
+The *Metallic* :abbr:`BSDF (Bidirectional Scattering Distribution Function)`
+node is used to recreate the appearance of metals.
+
+
+Inputs
+======
+
+F82 Tint
+--------
+
+Base Color
+   Color of the material when viewed straight on.
+
+Edge Tint
+   Color of the material when viewed at a 82° angle.
+
+Physical Conductor
+------------------
+
+IOR
+   Refractive index per color channel. This is the real part of a complex refractive index,
+   scientifically denoted as n.
+
+Extinction
+   Extinction coefficients per color channel. This is the imaginary part of a
+   complex refractive index, scientifically denoted as k.
+
+Common
+------
+
+Roughness
+   Sharpness of the reflection; perfectly sharp at 0.0 and smoother with higher values.
+
+Anisotropy :guilabel:`Cycles Only`
+   Amount of anisotropy. Higher values give elongated highlights along the tangent direction;
+   negative values give highlights shaped perpendicular to the tangent direction.
+
+Rotation :guilabel:`Cycles Only`
+   Rotates the direction of anisotropy, with 1.0 going full circle.
+
+   Compared to the *Glossy BSDF* node, the direction of highlight elongation
+   is rotated by 90°. Add 0.25 to the value to correct.
+
+Normal
+   Normal used for shading; if nothing is connected the default shading normal is used.
+
+Tangent
+   Tangent used for shading; if nothing is connected the default shading tangent is used.
+
+
+Properties
+==========
+
+Distribution
+   Microfacet distribution to use.
+
+   :GGX:
+      GGX microfacet distribution.
+   :Multiscatter GGX:
+      Takes multiple scattering events between microfacets into account.
+      This gives more energy conserving results, which would otherwise be visible as excessive darkening.
+   :Beckmann: :guilabel:`Cycles Only`
+      Beckmann microfacet distribution.
+
+Fresnel Type
+   Models for describing the metal's appearance, by specifying the apparent color or the physical IOR.
+
+   :F82 Tint:
+      Uses the `Adobe F82-Tint formula <https://helpx.adobe.com/content/dam/substance-3d/general-knowledge/asm/Adobe%20Standard%20Material%20-%20Technical%20Documentation%20-%20May2023.pdf>`__
+      for the metallic fresnel. This allows for artist friendly control of the color near the edge of the
+      material to simulate a complex IOR.
+   :Physical Conductor:
+      Accepts Complex IOR measurements from real world metals to replicate a more accurate rendering
+      of metals than the *F82 Tint* Fresnel type.
+
+      Complex IOR values can be found from sources like the
+      `Physically Based database for CG artists <https://physicallybased.info/>`__
+      and `Refractive Index nk database <https://refractiveindex.info/>`__.
+
+
+Outputs
+=======
+
+BSDF
+   Standard shader output.
+
+
+Examples
+========
+
+F82 Tint
+--------
+
+.. list-table::
+   :widths: 12 22 22 22 22
+
+   * -
+     - .. figure:: /images/render_shader-nodes_shader_metallic_f82-Ti.webp
+     - .. figure:: /images/render_shader-nodes_shader_metallic_f82-Al.webp
+     - .. figure:: /images/render_shader-nodes_shader_metallic_f82-Cu.webp
+     - .. figure:: /images/render_shader-nodes_shader_metallic_f82-Au.webp
+   * - Material
+     - Titanium (Default)
+     - Aluminum
+     - Copper
+     - Gold
+   * - Base Color
+     - 0.617, 0.576, 0.540
+     - 0.911, 0.912, 0.917
+     - 0.972, 0.694, 0.486
+     - 1.000, 0.735, 0.353
+   * - Edge Tint
+     - 0.695, 0.726, 0.770
+     - 0.848, 0.877, 0.916
+     - 0.961, 0.969, 0.942
+     - 0.993, 1.000, 1.000
+
+Physical Conductor
+------------------
+
+.. list-table::
+   :widths: 12 22 22 22 22
+
+   * -
+     - .. figure:: /images/render_shader-nodes_shader_metallic_physical-Ti.webp
+     - .. figure:: /images/render_shader-nodes_shader_metallic_physical-Al.webp
+     - .. figure:: /images/render_shader-nodes_shader_metallic_physical-Cu.webp
+     - .. figure:: /images/render_shader-nodes_shader_metallic_physical-Au.webp
+   * - Material
+     - Titanium (Default)
+     - Aluminum
+     - Copper
+     - Gold
+   * - IOR
+     - 2.757, 2.512, 2.231
+     - 1.333, 0.945, 0.582
+     - 0.235, 0.729, 1.369
+     - 0.000, 0.470, 1.439
+   * - Extinction
+     - 3.867, 3.404, 3.009
+     - 7.434, 6.340, 5.181
+     - 5.666, 2.562, 2.227
+     - 182.6, 2.189, 1.660