From b8fc80ddc8993cbfb7d4ffca4a88e703b60b1c10 Mon Sep 17 00:00:00 2001 From: Jamie Portsmouth Date: Tue, 9 Dec 2025 13:53:36 +0000 Subject: [PATCH 1/2] Add a preliminary CHANGELOG.md. --- CHANGELOG.md | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) create mode 100644 CHANGELOG.md diff --git a/CHANGELOG.md b/CHANGELOG.md new file mode 100644 index 00000000..0a2bdba7 --- /dev/null +++ b/CHANGELOG.md @@ -0,0 +1,37 @@ + +# Change Log + +This file gives a high level overview of the changes introduced between versions, relative to version 1.0. + +## [1.2] - Unreleased + +- #277: This will ensure defined and portable behavior across renderers. + +- #256: This PR adds a safety clamp to the result of metallic F82-tint model Fresnel calculations, preventing any negative reflectance values and therefore improving physical correctness and rendering quality for metallic surfaces. + +- #247: This alters the behavior of `specular_weight` when applied to the dielectric base, so that the refraction direction is *not* modified by `specular_weight`, +as this control is designed to vary only the reflectivity without disturbing the refraction appearance. Thus the reflection highlight and the refraction direction are +effectively decoupled, in an unphysical but artistically convenient way. + +- #240: Fixes a bug in the MaterialX graph, where the edge-tint color for the generalized_schlick_bsdf was multiplied by `specular_weight`, but the whole lobe was multiplied by `specular_weight` as well. + +- #251: Fixes a bug in the MaterialX implementation of thin-walled subsurface, where `specular_color` was accounted for in both the BSDF weights and as an explicit multiplier. + +- #250: This PR ensures that the `geometry_thin_walled` property, which indicates if a material's geometry should be treated as "thin-walled" (i.e., like a sheet or membrane without interior volume), is correctly connected to and represented within the node of MaterialX. + +- #238: Prior to this change, if `specular_weight` was set to a value greater than 1, it could lead to unphysical metallic Fresnel factors > 1. By introducing the clamp, the code ensures that, regardless of the value given to specular_weight, the resulting metal Fresnel reflectance remains within a physical range. + +- #231: Introduces a new parameter called `emission_weight`, providing a simple $[0,1]$ dimensionless scale facto r for the `emission_luminance`. + + +## [1.1] - Jun 28, 2024 + + - #211: This won't make much difference to the look in implementations that ignore the adjacent IORs of the film, but for those that take it into account, this will make the film visible rather than invisible by default (since `specular_ior` is 1.5 by default, and `coat_ior` 1.6). + + - #217: This change enables Zeltner sheen in the reference implementation of OpenPBR, leveraging the new functionality in MaterialX. + +## [1.0] - Jun 4, 2024 + + - _First release._ + + From b4f85feaff20d43597ac9ec50cfeb6b060766a58 Mon Sep 17 00:00:00 2001 From: Adrien Herubel Date: Tue, 9 Dec 2025 15:07:13 +0000 Subject: [PATCH 2/2] Revise CHANGELOG for version 1.2 updates Updated the CHANGELOG to reflect recent enhancements and bug fixes, including changes to specular behavior and new parameters. Signed-off-by: Adrien Herubel --- CHANGELOG.md | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) diff --git a/CHANGELOG.md b/CHANGELOG.md index 0a2bdba7..793dce7b 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -5,24 +5,21 @@ This file gives a high level overview of the changes introduced between versions ## [1.2] - Unreleased +### Look changing enhancements - #277: This will ensure defined and portable behavior across renderers. - - #256: This PR adds a safety clamp to the result of metallic F82-tint model Fresnel calculations, preventing any negative reflectance values and therefore improving physical correctness and rendering quality for metallic surfaces. - - #247: This alters the behavior of `specular_weight` when applied to the dielectric base, so that the refraction direction is *not* modified by `specular_weight`, as this control is designed to vary only the reflectivity without disturbing the refraction appearance. Thus the reflection highlight and the refraction direction are effectively decoupled, in an unphysical but artistically convenient way. - - #240: Fixes a bug in the MaterialX graph, where the edge-tint color for the generalized_schlick_bsdf was multiplied by `specular_weight`, but the whole lobe was multiplied by `specular_weight` as well. - - #251: Fixes a bug in the MaterialX implementation of thin-walled subsurface, where `specular_color` was accounted for in both the BSDF weights and as an explicit multiplier. - - #250: This PR ensures that the `geometry_thin_walled` property, which indicates if a material's geometry should be treated as "thin-walled" (i.e., like a sheet or membrane without interior volume), is correctly connected to and represented within the node of MaterialX. - +- #231: Introduces a new parameter called `emission_weight`, providing a simple $[0,1]$ dimensionless scale facto r for the `emission_luminance`. - #238: Prior to this change, if `specular_weight` was set to a value greater than 1, it could lead to unphysical metallic Fresnel factors > 1. By introducing the clamp, the code ensures that, regardless of the value given to specular_weight, the resulting metal Fresnel reflectance remains within a physical range. -- #231: Introduces a new parameter called `emission_weight`, providing a simple $[0,1]$ dimensionless scale facto r for the `emission_luminance`. +### Additive enhancements +### Bug fixes ## [1.1] - Jun 28, 2024