Materials
All objects around us are created from a variety of materials: metal, glass, plastic, rubber, etc. Materials along with the shape of the object, determine its appearance. In MANU, a material is a set of characteristics that, to a certain degree, affect the display of an object's surface in the game. Materials create greater realism in a scene and describe how an object reflects or transmits light. One game project can contain many different materials. Each material has different uses and property settings.
This article provides a detailed overview of material settings in Edit mode and Animation mode.
Materials are data-blocks that can be assigned to an object. Edit mode is the default workspace for setting up materials in MANU. To set up a material, select an object from your scene, then switch to the Material tab in the Inspector panel. Material tab includes material properties of the selected object, such as color, opacity type, shader properties, textures , and other settings.
Color is an important material characteristic for creating renders and assets that are physically accurate and look great on multiple display devices. It is used both to ensure all parts of the pipeline interpret colors correctly, and to make artistic changes like exposure and color grading. In MANU, you can adjust the selected object’s color via a color picker widget. In color picker you can select and adjust color values either by using the Default Palette, RGB, HSV color model or by manually entering the color code.
The RGB (Red, Green, Blue) color model defines a color space in terms of three components:
Red, which ranges from 0-255
Green, which ranges from 0-255
Blue, which ranges from 0-255
The HSV (Hue, Saturation, Value) color model defines a color space in terms of three constituent components:
Hue is the color type, such as red, blue, or yellow. It ranges from 0 to 360°. Each value corresponds to one color: 0 is red, 45 is a shade of orange and 55 is a shade of yellow.
Saturation is the intensity of the color that ranges from 0 to 100%, where 0 means no color, that is a shade of grey between black and white; 100 means intense color.
Value is the brightness of the color. It ranges from 0 to 100%, where 0 is always black; depending on the saturation, 100 may be white or a more or less saturated color.
Objects vary in how they transmit light. Opacity type setting determines the degree objects could block light from traveling through them. The light in the 3D world can be reflected by the object or absorbed and converted into thermal energy.
MANU materials have three types of opacity to select from:
Opaque
Transparent
Cut Out
To choose the correct opacity type for an object, let’s take a closer look at each of these types below.
Opaque material refers to commonly used materials that are neither metallic (strong reflections) nor transparent (refractive). For example, plastic, wood, stone, ceramic are the most common types of opaque materials in which most of the light is not reflected by the surface, and instead scattered by the interior in a very small volume. This scattering is what is known as the diffuse color, or simply the color of the material, and is the prominent visible feature of such materials.
The opaque materials are also known as translucent, where the light scattering is wide enough to soften surface details.
Transparent type of object’s opacity allows light to travel through these objects without any scattering, but with some degree of color absorption. Materials like air, water, and clear glass are called transparent. When light encounters transparent materials, almost all of it passes directly through them. Glass, for example, is commonly transparent to all visible light. The absorption is the apparent color of the interior of the material, and is always associated with a specific distance. The further the light travels inside the material the darker the color will become.
When the transparent type of opacity material is selected in MANU, you can adjust it’s opacity value and the type of blending.
In MANU, the opacity value for transparent materials ranges from 0 to 100%, where 75% is the default value. Opacity value at 0% would make the object’s material invisible in the scene.
Blending option performs mathematical calculations in the color information of a texture so that one texture can blend into another in a particular manner. There are two types of blending to select from - normal and additive. Normal blending blends the textures in such a way that the darker the blending color the more of that color will be used in the final result. Additive type of blending brightens the colors of everything beneath it. In MANU, normal is the default type of blending for transparent materials.
A Cut Out type of opacity is normally used to create holes in a surface. A cut out makes the material invisible where the texture is black, and fully visible where white. Cut out does not make a material “transparent” as a transparent material still reflects and refracts. Since it is purely a surface effect, it's best suited for thin objects like wire meshes or laser cut panels.
Note that Cut Out can only use textures instead of solid colors. It is possible to use a uniformly grey texture to partially fade an otherwise solid material to show something behind for illustration purposes. Just keep in mind that the result is not physically possible and might not work as expected in some cases.
The opacity value for Cut Out material works a little different than for opaque and transparent types of materials. If the Alpha texture doesn’t have sharp black and white edges, but soft transitions, the opacity value will change the size of holes (white area) in the texture. In MANU, the higher the opacity value, the smaller the holes are.
A shader determines how the object’s surface responds to light. One of the most noticeable features of each shader is how it generates specular highlights. The idea behind shader is to create a user-friendly way of achieving a consistent, plausible look under different lighting conditions. In MANU, a material specifies one specific shader to select from. The shader type determines which options are available in the Material. MANU allows you to assign your own texture assets and set up texture variables.
Textures are represented by bitmap images. A material can contain references to textures, so that the material’s shader can use the textures while calculating the surface color of an object. In addition to basic shader surfaces, textures can represent many other aspects of a material’s surface such as its glosiness or roughness.
There are several types of shader in MANU:
Basic
Normal
RIM
Glass
Metal
Toon
Standard
PBR
MatCap
Normal shader is an advanced version of the basic one. It can reflect the texture of objects and cast shadows from objects.
Glossiness computes the same simple lighting as Diffuse, plus a viewer dependent glossiness highlight. It is used to add reflection with microfacet distribution, used for materials such as metal or mirrors.
Glossiness Color is the color of glossiness effect - the surface, or physically speaking, the probability that light is reflected for each wavelength.
Emission defines how light is emitted from the surface, allowing any surface to become a light source. Emissive Color is a color of the emitted light.
A RIM shader is designed to achieve a lighting effect related to the contour/outline edges of an object. RIM can be useful for creating fresnel or cartoon-like skin effects.
RIM Value is a degree of a lighting effect applied to the contour/outline edges of an object. RIM values are within 0 to 100 units. The higher the value, the more lightning will be applied to an object’s edges.
RIM Color is the color of the RIM effect of an object's material.
Glossiness computes the same simple lighting as Diffuse, plus a viewer dependent glossiness highlight. It is used to add reflection with microfacet distribution, used for materials such as metal or mirrors.
Glossiness Color is the color of glossiness effect - the surface, or physically speaking, the probability that light is reflected for each wavelength.
Emission defines how light is emitted from the surface, allowing any surface to become a light source. Emissive Color is a color of the emitted light.
The Glass shader is used to add a glass-like shader refraction. Like the transparent shader, only pure white will make the object’s material transparent.
The Refraction effect is used to add glossy refraction with sharp or microfacet distribution. It is used for materials that transmit light. The default value for refraction is 0.5 units.
Glossiness computes the same simple lighting as Diffuse, plus a viewer dependent glossiness highlight. It is used to add reflection with microfacet distribution, used for materials such as metal or mirrors.
Glossiness Color is the color of glossiness effect - the surface, or physically speaking, the probability that light is reflected for each wavelength.
Emission defines how light is emitted from the surface, allowing any surface to become a light source. Emissive Color is a color of the emitted light.
A cubemap is a collection of six square textures that represent the reflections on an environment. Cubemaps are often used to capture reflections or “surroundings” of objects; for example skyboxes and environment reflections often use cubemaps.
SCREENSHOT
Metal shader provides realistic-looking metallic surfaces and a variety of organic-looking materials.
A cubemap is a collection of six square textures that represent the reflections on an environment. Cubemaps are often used to capture reflections or “surroundings” of objects; for example skyboxes and environment reflections often use cubemaps.
SCREENSHOT
Glossiness computes the same simple lighting as Diffuse, plus a viewer dependent glossiness highlight. It is used to add reflection with microfacet distribution, used for materials such as metal or mirrors.
Glossiness Color is the color of glossiness effect - the surface, or physically speaking, the probability that light is reflected for each wavelength.
Emission defines how light is emitted from the surface, allowing any surface to become a light source. Emissive Color is a color of the emitted light.
Toon shader is a type of non-photorealistic rendering that makes an object's material appear flat by using less shading color instead of a shade gradient or tints.
Glossiness computes the same simple lighting as Diffuse, plus a viewer dependent glossiness highlight. It is used to add reflection with microfacet distribution, used for materials such as metal or mirrors.
Glossiness Color is the color of glossiness effect - the surface, or physically speaking, the probability that light is reflected for each wavelength.
Emission defines how light is emitted from the surface, allowing any surface to become a light source. Emissive Color is a color of the emitted light.
The Standard shader is designed with hard surfaces in mind, and can deal with most real-world materials like stone, glass, ceramics, brass, silver or rubber.
With the Standard shader, a large range of shader types (such as Diffuse, Normal, Specular, AO, Emissive) are combined into a single shader intended to be used across all material types. The benefit of this is that the same lighting calculations are used in all areas of your scene, which gives a realistic, consistent and believable distribution of light and shade across all models that use the shader.
Diffuse — this parameter controls the base color of the surface. It is common to assign a texture map for this parameter. It’s important to note that the texture should not contain any lighting, since the lighting will be added to it based on the context in which the object is seen.
Normal — this shader works with RGB normal map images.
AO (Ambient Occlusion) — simulates the soft shadows that occur in holes, and other surfaces that are close to each other. These areas occlude (block out) ambient light, so they appear darker.
Specular — Specular shaders create the bright highlights that one would see on a glossy surface, mimicking the reflection of light sources. Unlike diffuse, specular reflection is dependent on the viewpoint.
Emissive — it defines how light is emitted from the surface, allowing any surface to become a light source.
This percentage value is normally used for objects that contain deepenings. The default value is 1%.
Glossiness computes the same simple lighting as Diffuse, plus a viewer dependent glossiness highlight. It is used to add reflection with microfacet distribution, used for materials such as metal or mirrors.
Glossiness Color is the color of glossiness effect - the surface, or physically speaking, the probability that light is reflected for each wavelength.
Emission defines how light is emitted from the surface, allowing any surface to become a light source. Emissive Color is a color of the emitted light.
Physically-based rendering (PBR) is a shading method used to accurately represent the interaction of light with surfaces. One thing that's different with PBR versus other shader types is thinking about what a material is made of in order to determine it's behaviour. For example, the main thing that is considered here is whether the material is a conductor (usually a metal) or an insulator (a non-metal).
PBR determines many factors about how the material responds to light. For example, metals are generally reflective (between 60%-90%) whereas non-metals are not (0%-20%). Reflections on non-metals are usually white whereas metals will usually reflect the same color as the diffuse.
Normal is the PBR parameter (in percentages) that is normally used for objects that contain deepenings. The default value is 1%.
Ambient Occlusion is a shading and rendering method used for global background or indirect shading of objects. This method is used to add more realism to the render because it creates soft global shadows that contribute to the visual separation of objects.
Metalness is a parameter that acts as a mask that defines areas on a texture set or material that behave like a metal (white) and do not (black). The default value is 0.
The roughness parameter controls the sharpness of the reflection, from 0 (perfectly sharp) to 100 (very soft).
Emission defines how light is emitted from the surface, allowing any surface to become a light source. Emissive Color is a color of the emitted light.
To apply and repeat an image in the pattern, use Tiling. Tiling wraps the selected object with the texture image.
Each texture has material offset. In MANU, offset is always in Tiles, from 0-100. Offset of 50 means to shift by half of the current tile size. So, no matter what the tiling, if you see a texture is 1/2-way across a seam, offset 50 will fix it.
In MANU, other material settings include Bloom Threshold and Lightning.
The Bloom effect creates fringes of light extending from the borders of bright areas in an image, contributing to the illusion of an extremely bright light overwhelming the Main Camera. In MANU, Bloom Threshold is the clipping of the bloom glow to bright pixels. A value of 0% means no clipping. Larger values focus the bloom on the brightest pixels. The default value of bloom threshold is 20%.
Lightning is the intensity of the bloom effect that can be set either per pixel or per vertex.
