Differential D2503 Diff 8241 C:/Users/Aaron/BlenderDev/bf_manual/trunk/blender_docs/manual/glossary/index.rst
Changeset View
Changeset View
Standalone View
Standalone View
C:/Users/Aaron/BlenderDev/bf_manual/trunk/blender_docs/manual/glossary/index.rst
| Property | Old Value | New Value |
|---|---|---|
| svn:eol-style | native \ No newline at end of property | LF \ No newline at end of property |
| Context not available. | |||||
| Glossary | Glossary | ||||
| ########### | ########### | ||||
| .. For writing style guide, see: :doc:`/about/contribute/style_guides/writing_guide` | These following pages lists terms and defintions that are used in this manual | ||||
| If you add new entries, keep the alphabetical sorting! | as well as terms that are important to a 3D artist. | ||||
| This page lists definitions for terms used in Blender and this manual. | .. toctree:: | ||||
| :maxdepth: 2 | |||||
| .. glossary:: | blender_terms.rst | ||||
| computer_graphics.rst | |||||
| Active | math.rst | ||||
| One of the three :doc:`selection states </editors/3dview/object/selecting>`. | color_theory.rst | ||||
| Only one object or item can be active at any given time. | |||||
| Action Safe | |||||
| Area of the screen visible on most devices. Place content inside it to ensure it does not get cut off. | |||||
| Actuator | |||||
| A :term:`logic brick` that acts like a muscle of a lifeform. It can move the object, or make a sound. | |||||
| Aliasing | |||||
| Rendering artifacts in the form of jagged lines. | |||||
| Alpha Channel | |||||
| Additional channel in an image for transparency. | |||||
| Straight Alpha | |||||
| Method where RGBA channels are stored as (R, G, B, A) | |||||
| channels, with the RGB channels unaffected by the alpha channel. | |||||
| This is the alpha type used by paint programs such as Photoshop or Gimp, | |||||
| and used in common file formats like PNG, BMP or Targa. | |||||
| So, image textures or output for the web are usually straight alpha. | |||||
| Premultiplied Alpha | |||||
| Method where RGBA channels are stored as (R × A, G × A, B × A, A), | |||||
| with the alpha multiplied into the RGB channel. | |||||
| This is the natural output of render engines, | |||||
| with the RGB channels representing the amount of light that comes toward the viewer, | |||||
| and alpha representing how much of the light from the background is blocked. | |||||
| The OpenEXR file format uses this alpha type. | |||||
| So, intermediate files for rendering and compositing are often stored as premultiplied alpha. | |||||
| Conversion (Straight/Premultiplied) Alpha | |||||
| Conversion between the two alpha types is not a simple operation and can involve data loss, | |||||
| as both alpha types can represent data that the other cannot though it is often subtle. | |||||
| Straight alpha can be considered to be an RGB color image with a separate alpha mask. | |||||
| In areas where this mask is fully transparent, there can still be colors in the RGB channels. | |||||
| On conversion to premultiplied alpha this mask is *applied'* | |||||
| and the colors in such areas become black and are lost. | |||||
| Premultiplied alpha, on the other hand, can represent renders | |||||
| that are both emitting light and letting through light from the background. | |||||
| For example, a transparent fire render might be emitting light, | |||||
| but also letting through all light from objects behind it. | |||||
| On converting to straight alpha, this effect is lost. | |||||
| Ambient Light | |||||
| The light that comes from the surrounding environment as a whole. | |||||
| Ambient Occlusion | |||||
| A ratio of how much :term:`ambient light` a surface point would be likely to receive. | |||||
| If a surface point is under a foot or table, | |||||
| it will end up much darker than the top of someone's head or the tabletop. | |||||
| Animation | |||||
| Simulation of motion. | |||||
| Anti-aliasing | |||||
| See :term:`oversampling`. | |||||
| Armature | |||||
| An :term:`Object` consisting of :term:`bones <bone>`. Used to :term:`rig` characters, props, etc. | |||||
| Axis | |||||
| A reference line which defines coordinates along one cardinal direction in n-D space. | |||||
| Axis Angle | |||||
| Rotation method where X, Y, and Z correspond to the axis definition, | |||||
| while W corresponds to the angle around that axis, in radians. | |||||
| Baking | |||||
| The process of computing and storing the result of a potentially time-consuming calculation | |||||
| so as to avoid needing to calculate it again. | |||||
| Bevel | |||||
| The operation to chamfer or bevel edges of an object. | |||||
| BU | |||||
| Blender Units | |||||
| Internal units used by Blender, equivalent to meters. Often abbreviated to "BU". | |||||
| Bone | |||||
| The building block of an :term:`Armature`. Made up of a :term:`Head`, :term:`Tail` | |||||
| and :term:`Roll Angle` which define a set of local axes and a point of rotation at the :term:`Head`. | |||||
| Boolean | |||||
| A type of logic dealing with binary true/false states. | |||||
| See also :doc:`Boolean Modifier </modeling/modifiers/generate/booleans>`. | |||||
| Bounce | |||||
| Refers to the reflection or transmission of a light ray upon interaction with a material. | |||||
| See also :doc:`Light Paths </render/cycles/settings/light_paths>`. | |||||
| Bounding Box | |||||
| The box that encloses the shape of an object. The box is aligned with the local space of the object. | |||||
| Bump Mapping | |||||
| Technique for simulating slight variations in surface height using a grayscale "height-map" texture. | |||||
| Bézier | |||||
| A computer graphics technique for generating and representing curves. | |||||
| BVH | |||||
| Bounding Volume Hierarchy | |||||
| A hierarchical structure of geometric objects. | |||||
| See also `Bounding Volume Hierarchy <https://en.wikipedia.org/wiki/Bounding_volume_hierarchy>`__ on Wikipedia. | |||||
| Caustics | |||||
| Bright concentrations of light focused by specularly reflecting or refracting objects. | |||||
| Child | |||||
| An :term:`Object` that is affected by its :term:`Parent`. | |||||
| Chroma | |||||
| Chrominance | |||||
| In general, a resulting image color decomposition, where its (*L* or *Y*) luminance channel is separated. | |||||
| There are two different contexts whereas this term is used: | |||||
| Video systems | |||||
| Refers to the general color decomposition resulting in *Y* (Luminance) and *C* (Chrominance) channels, | |||||
| whereas the chrominance is represented by: U = ( Blue minus Luminance ) and V = ( Red minus Luminance ). | |||||
| Matte compositing | |||||
| Refers to a point in the color gamut surrounded by a mixture | |||||
| of a determined spectrum of its RGB neighboring colors. | |||||
| This point is called *Chroma key* and this key | |||||
| (a chosen color) is used to create an *Alpha Mask*. | |||||
| The total amount of gamut space for this chrominance point is defined | |||||
| by users in a circular or square shaped format. | |||||
| Clamp | |||||
| Clamping | |||||
| Limits a variable to a range. The values over or under the range are set | |||||
| to the constant values of the ranges minimum or maximum. | |||||
| Blend Modes | |||||
| Color Blend Modes | |||||
| Methods for blending two colors together. | |||||
| See also `Blend Modes <https://docs.gimp.org/en/gimp-concepts-layer-modes.html>`__ on GIMP docs. | |||||
| Color Space | |||||
| A coordinate system in which a vector represent a color value. | |||||
| RGB | |||||
| Red-Green-Blue traditional primary colors also broadcast directly to most computer monitors. | |||||
| HSV | |||||
| Three values, often considered as more intuitive (human perception) than the RGB system. | |||||
| Hue | |||||
| The Hue of the color. | |||||
| Saturation | |||||
| The quantity of hue in the color (from desaturated -- a shade of gray -- to saturated -- brighter colors). | |||||
| Value | |||||
| The brightness of the color (dark to light). | |||||
| HSL | |||||
| Hue, Saturation | |||||
| See HSV. | |||||
| Luminance | |||||
| TODO. | |||||
| YUV | |||||
| Luminance-Chrominance standard used in broadcasting analog PAL (European) video. | |||||
| YCbCr | |||||
| Luminance-ChannelBlue-ChannelRed Component video for digital broadcast use, | |||||
| whose standards have been updated for HDTV and commonly referred to as the HDMI format for component video. | |||||
| \+A | |||||
| The color space holds an additional :term:`Alpha Channel`. | |||||
| Concave face | |||||
| Face in which one vertex is inside a triangle formed by other vertices of the face. | |||||
| Constraint | |||||
| A way of controlling one :term:`object` with data from another. | |||||
| Controller | |||||
| A :term:`logic brick` that acts like the brain of a lifeform. | |||||
| It makes decisions to activate muscles (:term:`actuators <actuator>`), | |||||
| using either simple logic or complex Python scripts. | |||||
| Convex face | |||||
| Face where, if lines were drawn from each vertex to every other vertex, all lines would remain in the face. | |||||
| Opposite of a :term:`concave face`. | |||||
| Coplanar | |||||
| Refers to any set of elements that are all aligned to the same 2D plane in 3D space. | |||||
| Crease | |||||
| Property of an :term:`edge`. Used to define the sharpness of edges in :term:`subdivision surface` meshes. | |||||
| Curve | |||||
| A type of object defined in terms of a line interpolated between Control Vertices. | |||||
| Available types of curves include :term:`Bézier` and :term:`NURBS`. | |||||
| Cyclic | |||||
| Often referring to an object being circular. This term is often associated with :term:`Curve`. | |||||
| DOF | |||||
| Depth Of Field | |||||
| The distance in front of and behind the subject which appears to be in focus. | |||||
| For any given lens setting, there is only one distance at which a subject is precisely in focus, | |||||
| but focus falls off gradually on either side of that distance, | |||||
| so there is a region in which the blurring is tolerable. | |||||
| This region is greater behind the point of focus than it is in front, | |||||
| as the angle of the light rays change more rapidly; they approach being parallel with increasing distance. | |||||
| Diffuse Light | |||||
| Even, directed light coming off a surface. | |||||
| For most things, diffuse light is the main lighting we see. | |||||
| Diffuse light comes from a specific direction or location and creates shading. | |||||
| Surfaces facing towards the light source will be brighter, | |||||
| while surfaces facing away from the light source will be darker. | |||||
| Directional Light | |||||
| The light that has a specific direction, but no location. | |||||
| It seems to come from an infinitely far away source, like the sun. | |||||
| Surfaces facing the light are illuminated more than surfaces facing away, but their location does not matter. | |||||
| A Directional Light illuminates all objects in the scene, no matter where they are. | |||||
| Displacement Mapping | |||||
| Method for distorting vertices based on an image or texture. | |||||
| Similar to :term:`Bump Mapping`, but instead operates on the mesh's actual geometry. | |||||
| This relies on the mesh having enough geometry to represent details in the image. | |||||
| Double Buffer | |||||
| Technique for drawing and displaying content on the screen. | |||||
| Blender uses two buffers (images) to draw the interface in. | |||||
| The content of one buffer is displayed while drawing occurs on the other buffer. | |||||
| When drawing is complete, the buffers are switched. | |||||
| Edge | |||||
| Straight segment (line) that connects two :term:`vertices <vertex>`, and can be part of a :term:`face`. | |||||
| Edge Loop | |||||
| Chain of :term:`edges <edge>` belonging to consecutive :term:`quads <quad>`. | |||||
| An edge loop ends at a pole or a boundary. Otherwise, it is cyclic. | |||||
| Edge Ring | |||||
| Path of all :term:`edges <edge>` along a :term:`face loop` that share two faces belonging to that loop. | |||||
| Empty | |||||
| An :term:`Object` without any :term:`Vertices`, :term:`Edges <Edge>` or :term:`Faces <Face>`. | |||||
| Environment Map | |||||
| A method of calculating reflections. | |||||
| It involves rendering images at strategic positions and applying them as textures to the mirror. | |||||
| Now in most cases obsoleted by Raytracing, which though slower is easier to use and more accurate. | |||||
| Euler | |||||
| Euler Rotation | |||||
| Rotation method where rotations applied on each X, Y, Z axis component. | |||||
| Face | |||||
| Mesh element that defines a piece of surface. It consists of three or more :term:`edges <edge>`. | |||||
| Face Loop | |||||
| Chain of consecutive :term:`quads <quad>`. | |||||
| A face loop stops at a :term:`triangle` or :term:`N-gon` (which do not belong to the loop), or at a boundary. | |||||
| Otherwise, it is cyclic. | |||||
| Face Normal | |||||
| The normalized vector perpendicular to the plane that a :term:`face` lies in. | |||||
| Each face has its own normal. | |||||
| F-Curve | |||||
| A curve that holds the animation values of a specific property. | |||||
| Field of View | |||||
| The area in which objects are visible to the camera. Also see :term:`Focal Length <focal length>` | |||||
| Focal Length | |||||
| The distance required by a lens to focus collimated light. | |||||
| Defines the magnification power of a lens. Also see :term:`Field of View <field of view>`. | |||||
| FSAA | |||||
| Full-Screen Anti-Aliasing | |||||
| A method of :term:`Anti-aliasing` on the graphics card, so the entire image is displayed smooth. | |||||
| Also known as *Multi-Sampling*. | |||||
| This can be enabled in the :ref:`User Preferences <prefs-system-multi-sampling>`. | |||||
| On many graphics cards, this can also be enabled in the driver options. | |||||
| Gamma | |||||
| An operation used to adjust the brightness of an image. | |||||
| See also `Gamma correction <https://en.wikipedia.org/wiki/Gamma_correction>`__ on Wikipedia. | |||||
| Geometric Center | |||||
| The mean average of the positions of all vertices making up the object. | |||||
| Gimbal | |||||
| A pivoted support that allows the rotation of an object about a single axis. | |||||
| See also `Gimbal <https://en.wikipedia.org/wiki/Gimbal>`__ on Wikipedia. | |||||
| Gimbal Lock | |||||
| The limitation where axes of rotation can become aligned, | |||||
| losing the ability to rotate on an axis (typically associated with :term:`euler rotation`). | |||||
| - See also `Gimbal lock <https://en.wikipedia.org/wiki/Gimbal_lock>`__ on Wikipedia. | |||||
| - See also `Gimbal lock <https://blender.stackexchange.com/questions/469>`__ on Stackexchange. | |||||
| Global Illumination | |||||
| A superset of radiosity and ray tracing. | |||||
| The goal is to compute all possible light interactions in a given scene, | |||||
| and thus, obtain a truly photo-realistic image. | |||||
| All combinations of diffuse and specular reflections and transmissions must be accounted for. | |||||
| Effects such as color bleeding and caustics must be included in a global illumination simulation. | |||||
| Global Space | |||||
| See :term:`World Space`. | |||||
| Gouraud Shading | |||||
| Used to achieve smooth lighting on low-polygon surfaces without the | |||||
| heavy computational requirements of calculating lighting for each pixel. | |||||
| The technique was first presented by Henri Gouraud in 1971. | |||||
| Glossy Map | |||||
| See :term:`Roughness Map`. | |||||
| Head | |||||
| A subcomponent of a :term:`Bone`. The point of rotation for that :term:`Bone`. | |||||
| Has X, Y and Z coordinates measured in the :term:`Local Space` of the :term:`Armature` :term:`Object`. | |||||
| Used in conjunction with the :term:`Tail` to define the :term:`local <Local Space>` Y axis of the :term:`Bone` | |||||
| in :term:`Pose Mode`. The larger of the two ends when drawn as an :term:`Octahedron`. | |||||
| HDRI | |||||
| High Dynamic Range Image | |||||
| A set of techniques that allow a far greater dynamic range of exposures than normal digital imaging | |||||
| techniques. The intention is to accurately represent the wide range of intensity levels found in real scenes, | |||||
| ranging from direct sunlight to the deepest shadows. | |||||
| See also `HDRI <https://en.wikipedia.org/wiki/HDRI>`__ on Wikipedia. | |||||
| IOR | |||||
| Index Of Refraction | |||||
| A property of transparent materials. | |||||
| When a light ray travels through the same volume it follows a straight path. | |||||
| However, if it passes from one transparent volume to another, it bends. | |||||
| The angle by which the ray is bent can be determined by the IOR of the materials of both volumes. | |||||
| Interpolation | |||||
| Method of calculating new data between points of known value, like :term:`keyframes <keyframe>`. | |||||
| Inverse Kinematics | |||||
| The process of determining the movement of interconnected segments of a body or model. | |||||
| Using ordinary Kinematics on a hierarchically structured object you can, for example, | |||||
| move the shoulder of a puppet. The upper and lower arm and hand will automatically follow that movement. | |||||
| IK will allow you to move the hand and let the lower and upper arm go along with the movement. | |||||
| Without IK the hand would come off the model and would move independently in space. | |||||
| Keyframe | |||||
| A frame in an animated sequence drawn or otherwise constructed directly by the user. | |||||
| In classical animation, when all frames were drawn by animators, | |||||
| the senior artist would draw these frames, leaving the "in between" frames to an apprentice. | |||||
| Now, the animator creates only the first and last frames of a simple sequence (keyframes); | |||||
| the computer fills in the gap. | |||||
| Keyframing | |||||
| Inserting :term:`Keyframes <Keyframe>` to build an animated sequence. | |||||
| Lattice | |||||
| A type of object consisting of a non-renderable three-dimensional grid of vertices. | |||||
| See also :doc:`Lattice Modifier </modeling/modifiers/deform/lattice>`. | |||||
| Layer | |||||
| A device for organizing objects. See also :doc:`Layers </editors/3dview/object/properties/relations/layers>`. | |||||
| Local Space | |||||
| A 3D coordinate system that originates (for Objects) at the :term:`Object Origin`. | |||||
| or (for Bones) at the :term:`Head` of the :term:`Bone`. | |||||
| Compare to :term:`World Space`. | |||||
| Logic brick | |||||
| A graphical representation of a functional unit in Blender's game logic. | |||||
| A Logic brick can be a :term:`Sensor`, :term:`Controller` or :term:`Actuator`. | |||||
| Manifold | |||||
| Manifold meshes, also called *water tight* meshes, | |||||
| define a *closed non-self-intersecting volume* (see also :term:`non-manifold`). | |||||
| A manifold mesh is a mesh in which the structure of the connected | |||||
| faces in a closed volume will always point the normals (and there | |||||
| surfaces) to the outside or to the inside of the mesh without any overlaps. | |||||
| If you recalculate those normals, they will always point at | |||||
| a predictable direction (To the outside or to the inside of the volume). | |||||
| When working with non-closed volumes, a manifold mesh is a mesh in which | |||||
| the normals will always define two different and non-consecutive surfaces. | |||||
| A manifold mesh will always define an even number of non-overlapped surfaces. | |||||
| Matte | |||||
| Mask | |||||
| A grayscale image used to include or exclude parts of an image. A matte is | |||||
| applied as an :term:`Alpha Channel`, or it is used as a mix factor when | |||||
| applying :term:`Color Blend Modes`. | |||||
| Mesh | |||||
| Type of object consisting of :term:`vertices <vertex>`, :term:`edges <edge>` and :term:`faces <face>`. | |||||
| Micropolygons | |||||
| A polygon roughly the size of a pixel or smaller. | |||||
| MIP | |||||
| Mipmap | |||||
| Mipmapping | |||||
| 'MIP' is an acronym of the Latin phrase 'multum in parvo', meaning 'much in little'. | |||||
| Mipmaps are progressively lower resolution representations of an image, | |||||
| generally reduced by half squared interpolations using antialiasing. | |||||
| Mipmapping is the procces used to calculate lower resolutions of the | |||||
| same image, reducing memory usage to help speed visualization, but increasing | |||||
| memory usage for calculations and allocation. Mipmapping is also a procces | |||||
| used to create small antialised samples of an image used for texturing. | |||||
| The mipmapping calculations are made by CPUs, but modern graphic processors | |||||
| can be selected for this task and are way faster. | |||||
| See the Mipmap option present in the :doc:`System Preferences </preferences/system>`. | |||||
| Motion Blur | |||||
| The phenomenon that occurs when we perceive a rapidly moving object. | |||||
| The object appears to be blurred because of our persistence of vision. | |||||
| Simulating motion blur makes computer animation appear more realistic. | |||||
| Multi-sampling | |||||
| See :term:`FSAA`. | |||||
| N-gon | |||||
| A :term:`face` that contains more than four :term:`vertices <vertex>`. | |||||
| Non-linear animation | |||||
| Animation technique that allows the animator to edit motions as a whole, | |||||
| not just the individual keys. Nonlinear animation allows you to combine, | |||||
| mix, and blend different motions to create entirely new animations. | |||||
| Non-manifold | |||||
| Non-Manifold meshes essentially define geometry which cannot exist in the real world. | |||||
| This kind of geometry is not suitable for several types of operations, | |||||
| especially those where knowing the volume (inside/outside) of the object is important | |||||
| (refraction, fluids, booleans, or 3D printing, to name a few). | |||||
| A non-manifold mesh is a mesh in which the structure of a | |||||
| non-overlapped surface (based on its connected faces) will not determine | |||||
| the inside or the outside of a volume based on its normals, defining | |||||
| a single surface for both sides, but ended with flipped normals. | |||||
| When working with non-closed volumes, a non-manifold mesh will always | |||||
| determine at least one discontinuity in the normal directions, either | |||||
| by an inversion of a connected loop, or by an odd number of surfaces. | |||||
| A non-manifold mesh will always define an odd number of surfaces. | |||||
| There are several types of non-manifold geometry: | |||||
| - Some borders and holes (edges with only a single connected face), as faces have no thickness. | |||||
| - Edges and vertices not belonging to any face (wire). | |||||
| - Edges connected to three or more faces (interior faces). | |||||
| - Vertices belonging to faces that are not adjoining (e.g. two cones sharing the vertex at the apex). | |||||
| See also: :ref:`Select Non-Manifold <mesh-select-non-manifold>` tool. | |||||
| Normal | |||||
| The normalized vector perpendicular to a surface. | |||||
| Normals can be assigned to vertices, | |||||
| faces and modulated across a surface using :term:`normal mapping`. | |||||
| Normal mapping | |||||
| Is similar to :term:`Bump mapping`, but instead of the image being a grayscale heightmap, | |||||
| the colors define in which direction the normal should be shifted, | |||||
| the three color channels being mapped to the three directions X, Y and Z. | |||||
| This allows more detail and control over the effect. | |||||
| NURBS | |||||
| A computer graphics technique for generating and representing curves and surfaces. | |||||
| Object | |||||
| Container for a type (Mesh, Curve, Surface, Metaball, Text, Armature, | |||||
| Lattice, Empty, Camera, Lamp) and basic 3D transform data (:term:`Object Origin`). | |||||
| Object Center | |||||
| Object Origin | |||||
| A reference point used to position, rotate, and scale an :term:`Object` | |||||
| and to define its :term:`Local Space` coordinates. | |||||
| Octahedron | |||||
| An eight-sided figure commonly used to depict the :term:`Bones <Bone>` of an :term:`Armature`. | |||||
| OpenGL | |||||
| The graphics system used by Blender (and many other graphics applications) | |||||
| for drawing 3D graphics, often taking advantage of hardware acceleration. | |||||
| See also `OpenGL <https://en.wikipedia.org/wiki/OpenGL>`__ on Wikipedia. | |||||
| Oversampling | |||||
| Is the technique of minimizing :term:`aliasing` when representing a high-resolution | |||||
| signal at a lower resolution. | |||||
| Also called Anti-Aliasing. | |||||
| Overscan | |||||
| The term used to describe the situation. | |||||
| when not all of a televised image is present on a viewing screen. | |||||
| See also `Overscan <https://en.wikipedia.org/wiki/Overscan>`__ on Wikipedia. | |||||
| Parent | |||||
| An :term:`Object` that affects its :term:`Child` objects. | |||||
| Parenting | |||||
| Creating a :term:`Parent`-:term:`Child` relationship between two :term:`objects <Object>`. | |||||
| Particle system | |||||
| Technique that simulate certain kinds of fuzzy phenomena, | |||||
| which are otherwise very hard to reproduce with conventional rendering techniques. | |||||
| Common examples include fire, explosions, smoke, sparks, falling leaves, clouds, fog, snow, dust, | |||||
| meteor tails, stars and galaxies, or abstract visual effects like glowing trails, magic spells. | |||||
| Also used for things like: fur, grass or hair. | |||||
| Phong | |||||
| Local illumination model that can produce a certain degree of realism in three-dimensional | |||||
| objects by combining three elements: diffuse, specular and ambient for each considered point on a surface. | |||||
| It has several assumptions -- all lights are points, only surface geometry is considered, | |||||
| only local modeling of diffuse and specular, specular color is the same as light color, | |||||
| ambient is a global constant. | |||||
| Pivot Point | |||||
| The pivot point is the point in space around which all rotations, | |||||
| scalings and mirror transformations are centered. | |||||
| See also the :doc:`Pivot Point </editors/3dview/object/transform/control/pivot_point/index>` docs. | |||||
| Pixel | |||||
| The smallest unit of information in a 2D raster image, | |||||
| representing a single color made up of red, green, and blue channels. | |||||
| If the image has an :term:`alpha channel`, the pixel will contain a corresponding fourth channel. | |||||
| Pole | |||||
| :term:`Vertex` where three, five, or more edges meet. | |||||
| A vertex connected to one, two, or four edges is not a pole. | |||||
| Pose Mode | |||||
| Used for :term:`posing`, :term:`keyframing`, :term:`weight painting`, | |||||
| :term:`constraining <Constraint>` and :term:`parenting` the :term:`bones <Bone>` of an :term:`armature`. | |||||
| Posing | |||||
| Moving, Rotating and Scaling the :term:`bones <Bone>` of an :term:`armature` | |||||
| to achieve an aesthetically pleasing pose for a character. | |||||
| Premultiplied Alpha | |||||
| See :term:`Alpha Channel`. | |||||
| Primitive | |||||
| A basic object that can be used as a basis for modeling more complicated objects. | |||||
| Procedural Texture | |||||
| Computer generated (generic) textures. Procedural textures can be configured via parameters. | |||||
| Projection | |||||
| In computer graphics, there are two common camera projections used. | |||||
| Perspective | |||||
| A *perspective* view is geometrically constructed by taking a scene in 3D | |||||
| and placing an observer at point *O*. | |||||
| The 2D perspective scene is built by placing a plane (e.g. a sheet of paper) | |||||
| where the 2D scene is to be drawn in front of point *O*, | |||||
| perpendicular to the viewing direction. | |||||
| For each point *P* in the 3D scene a *PO* line is drawn, | |||||
| passing by *O* and *P*. The intersection point *S* between | |||||
| this *PO* line and the plane is the perspective projection of that point. | |||||
| By projecting all points *P* of the scene you get a perspective view. | |||||
| Orthographic | |||||
| In an *orthographic* projection, | |||||
| you have a viewing direction but not a viewing point *O*. The line is then drawn | |||||
| through point *P* so that it is parallel to the viewing direction. The intersection | |||||
| *S* between the line and the plane is the orthographic projection of the point | |||||
| *P*. | |||||
| By projecting all points *P* of the scene you get the orthographic view. | |||||
| Quad | |||||
| Quadrilateral | |||||
| Quadrangle | |||||
| :term:`Face` that contains exactly four :term:`vertices <vertex>`. | |||||
| Quaternion | |||||
| Quaternion Rotation | |||||
| Rotation method where rotations are defined by four values (X, Y, Z and W). | |||||
| X, Y, and Z also define an :term:`axis`, and W an angle, | |||||
| but it is quite different from :term:`Axis Angle`. | |||||
| Radiosity | |||||
| A global lighting method. | |||||
| that calculates patterns of light and shadow for rendering graphics images from three-dimensional models. | |||||
| One of the many different tools which can simulate diffuse lighting in Blender. | |||||
| See also | |||||
| `Radiosity (computer graphics) <https://en.wikipedia.org/wiki/Radiosity_%28computer_graphics%29>`__ | |||||
| on Wikipedia. | |||||
| Raytracing | |||||
| Rendering technique that works by tracing the path taken by a ray of light through the scene, | |||||
| and calculating reflection, refraction, or absorption of the ray whenever it intersects an object in the world. | |||||
| More accurate than :term:`scanline`, but much slower. | |||||
| Refraction | |||||
| The change in direction of a wave due to a change in velocity. | |||||
| It happens when waves travel from a medium with a given :term:`index of refraction` to a medium with another. | |||||
| At the boundary between the media, the wave changes direction; | |||||
| its wavelength increases or decreases but frequency remains constant. | |||||
| Render | |||||
| The process of computationally generating a 2D image from 3D geometry. | |||||
| Rig | |||||
| A system of relationships that determine how something moves. The act of building of such a system. | |||||
| Roll | |||||
| Roll Angle | |||||
| The orientation of the local X and Z axes of a :term:`Bone`. | |||||
| Has no effect on the local Y axis as local Y is determined by the location of the :term:`Head` and :term:`Tail`. | |||||
| Roughness Map | |||||
| A gray scale texture that defines how rough or smooth the surface of a material is. | |||||
| This may also be known as a :term:`Glossy Map`. | |||||
| Scanline | |||||
| Rendering technique. Much faster than :term:`raytracing`, | |||||
| but allows fewer effects, such as reflections, refractions, motion blur and focal blur. | |||||
| Sensor | |||||
| A :term:`logic brick` that acts like a sense of a lifeform. It reacts to touch, vision, collision etc. | |||||
| Shading | |||||
| Process of altering the color of an object/surface in the 3D scene, | |||||
| based on its angle to lights and its distance from lights to create a photorealistic effect. | |||||
| Smoothing | |||||
| Defines how :term:`faces <face>` are shaded. | |||||
| Face can be either solid (faces are rendered flat) | |||||
| or smooth (faces are smoothed by interpolating the normal on every point of the face). | |||||
| Specular light | |||||
| A light which is reflected precisely, like a mirror. | |||||
| Also used to refer to highlights on reflective objects. | |||||
| Straight Alpha | |||||
| See :term:`Alpha Channel`. | |||||
| Subsurface scattering | |||||
| Mechanism of light transport in which light penetrates the surface of a translucent object, | |||||
| is scattered by interacting with the material, and exits the surface at a different point. | |||||
| All non-metallic materials are translucent to some degree. | |||||
| In particular, materials such as marble, skin, | |||||
| and milk are extremely difficult to simulate realistically without taking subsurface scattering into account. | |||||
| Subdividing | |||||
| Technique for adding more geometry to a mesh. | |||||
| It creates new vertices on subdivided edges, new edges between subdivisions and new faces based on new edges. | |||||
| If new edges cross a new vertex is created at their crossing point. | |||||
| Subsurf | |||||
| Subdivision surface | |||||
| A method of creating smooth higher poly surfaces which can take a low polygon mesh as input. | |||||
| Sometimes abbreviated to **Subsurf**. | |||||
| See also | |||||
| `Catmull-Clark subdivision surface <https://en.wikipedia.org/wiki/Catmull%E2%80%93Clark_subdivision_surface>`__ | |||||
| on Wikipedia. | |||||
| Tail | |||||
| A subcomponent of a :term:`Bone`. Has X, Y and Z coordinates measured in the :term:`Local Space` | |||||
| of the Armature Object. Used in conjunction with the :term:`Head` | |||||
| to define the :term:`local <Local Space>` Y axis of a :term:`Bone` in :term:`Pose Mode`. | |||||
| The smaller of the two ends when drawn as an :term:`Octahedron`. | |||||
| Tessellation | |||||
| The tiling of a plane using one or more geometric shapes usually resulting in :term:`Micropolygons`. | |||||
| Texture | |||||
| Specifies visual patterns on surfaces and simulates physical surface structure. | |||||
| Texture Space | |||||
| The bounding box to use when using *Generated* mapping to add a :term:`Texture` to an image. | |||||
| Timecode | |||||
| A coded signal on videotape or film giving information about the frame number, time of recording, or exposure. | |||||
| Title Safe | |||||
| Area of the screen visible on all devices. | |||||
| Place text and graphics inside this area to make sure they do not get cut off. | |||||
| Topology | |||||
| The arrangement of *Vertices*, *Edges*, and *Faces* which define the shape of a mesh. | |||||
| See :term:`vertex`, :term:`edge`, and :term:`face`. | |||||
| Transforms | |||||
| The combined idea of location, rotation and scale. | |||||
| Triangle | |||||
| :term:`Face` with exactly three :term:`vertices <vertex>`. | |||||
| UV map | |||||
| Defines a relation between the surface of a mesh and a 2D texture. In detail, | |||||
| each face of the mesh is mapped to a corresponding face on the texture. | |||||
| It is possible and often common practice to map several faces of the mesh to the same | |||||
| or overlapping areas of the texture. | |||||
| Vertex | |||||
| Vertices | |||||
| A point in 3D space containing a location. It may also have a defined color. | |||||
| Vertices are the terminating points of :term:`edges <edge>`. | |||||
| Vertex Group | |||||
| Collection of :term:`vertices <vertex>`. | |||||
| Vertex groups are useful for limiting operations to specific areas of a mesh. | |||||
| Voxel | |||||
| A cubicle 3D equivalent to the square 2D pixel. | |||||
| The name is a combination of the terms "Volumetric" and ":term:`Pixel <pixel>`". | |||||
| Used to store smoke and fire data from physics simulations. | |||||
| Walk Cycle | |||||
| In animation, a walk cycle is a character that has just the walking function animated. | |||||
| Later on in the animation process the character is placed in an environment | |||||
| and the rest of the functions are animated. | |||||
| Weight Painting | |||||
| Assigning :term:`vertices` to :term:`Vertex Groups <Vertex Group>` with a weight of 0.0 - 1.0. | |||||
| World Space | |||||
| A 3D coordinate system that originates at a point at the origin of the world. | |||||
| Compare to :term:`Local Space`. | |||||
| Z-buffer | |||||
| Raster-based storage of the distance measurement between the camera and the surface points. | |||||
| Surface points which are in front of the camera have a positive Z value and | |||||
| points behind have negative values. The Z-Depth map can be visualized as a grayscale image. | |||||
| Context not available. | |||||