Rombotools tile blender shader is a powerful stochastic texture synthesizer. It fully preserves texture characteristics and features. Basically it allows to have a texture as input and produce an infinite, non-repeating render-time texture from that. Effectively as soon we start increasing UV repetitions on our texture what we get back is some awful tile artifacts.[…]
This is an advanced utility able to blur both bitmap textures and whole procedural shading graphs. This is useful for visual stuff where you may want to blur accordling to match some renditions you have in mind and/or to improve antialiasing with procedurals nodes. All we have to do is to put it on the[…]
A thickness shader is a type of shader used to simulate the thickness or volume of an object in a 3D scene. It allows for the creation of more realistic and detailed models by adding depth and dimension to otherwise flat or thin objects. The thickness shader works by calculating the distance between the surface[…]
With latest v1.1 update, we added : a full new shading node, romboReflectRetro full PBR support to the Glints node custom map support for the Glints node automatic fix for bad inverted normals for SSS-RW a new multiple scattering mode to ReflectMultiScatter a re-work of some internal code to be overally faster a new batch[…]
Retroreflection is an optical phenomenon where light scatters back to its source along the inverted incident direction. Materials with retroreflection properties are used for safety garments to help enhance visibility in low-light conditions like roads at night when illuminated by car headlights. Traffic signs and pavement markings also use materials with such properties to ensure[…]
In our quest for an improved diffuse model we already seen a principled implementation and a super smooth lambertian sphere model. We’ll briefly see here a ‘microfacet’ lambertian model that comes with the DiffuseRough shading node. As before we don’t really need to fully understand all of this but a general understading is still better[…]
SkinLayers material is a three layers SSS dipole implementation in the style of the old alSurface material with added features like ‘peach fuzz’ reflections and ad-hoc params to better control overall sss appearance. Works great for anything releated to subsurface scattering and remains super easy and intuitive to use. Here for this Judge Dredd’s caricature[…]
In our journey on diffuse shading we have seen how a diffuse principled implementation better suites modern workflows than the classical Oren-Nayar implementation. The main offender on the Oren-Nayar implementation (rombo DiffuseGeneralized, Arnold Std Material) is that it is based on single scattering and so it leaks energy (diffuse gets too dark with increasing roughness).[…]
Reflections are a complex matter. However we don’t need to fully understand them to be able to use them in a CG workflow, after all reflection slope for example is just a single parameter we may better grasp just looking at the different results we get while tweaking it. But we can still read the[…]
Because Rombo shading nodes are organized by lobes (diffuse, reflect, sss etc.) we need to choose the right one for the work we gonna do. When we have a metalness map for example we have 3 nodes we can choose from : ReflectGeneralized, ReflectMultiScatter and ReflectFlakes. Being ‘reflect’ nodes the initial setup is of pure[…]
Generally diffuse and specular lobes are layered making use of the Fresnel reflectance at the interface. This simply means that the diffuse lobe is multiplied by 1-Fresnel while the specular lobe is added on top. Practically it means that when Fresnel is at max (at grazing angles) we have only reflections showing up. This ensure[…]
When we generally talk about ‘diffuse’, technically we intend the relationship between surface normals and light direction such that the diffuse model is : N.L. This reads, – N dot L. When we take the dot of two vectors we measure the scalar magnitude between them. Here that means we get the magnitude of the[…]