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Projection Plane
A projection plane, or plane of projection, is a type of view in which graphical projections from an object intersect.Gary R. Bertoline et al. (2002) ''Technical Graphics Communication''. McGraw–Hill Professional, 2002. , p. 330. Projection planes are used often in descriptive geometry and graphical representation. A picture plane in perspective drawing is a type of projection plane. With perspective drawing, the lines of sight, or projection lines, between an object and a picture plane return to a vanishing point and are not parallel. With parallel projection the lines of sight from the object to the projection plane are parallel. File:Perspective projection of triangle ABC on plane Π from point S.svg , Perspective projection of triangle ABC on plane Π from point S. File:Axonometric_projection.svg , Axonometric projection on projection plane Π File:Perspectiva-1.svg , A cube in two-point perspective File:Perspectiva-2.svg , Simulated rays of light travel from the object, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Descriptive Geometry
Descriptive geometry is the branch of geometry which allows the representation of three-dimensional objects in two dimensions by using a specific set of procedures. The resulting techniques are important for engineering, architecture, design and in art. The theoretical basis for descriptive geometry is provided by planar geometric projections. The earliest known publication on the technique was "Underweysung der Messung mit dem Zirckel und Richtscheyt", published in Linien, Nuremberg: 1525, by Albrecht Dürer. Italian architect Guarino Guarini was also a pioneer of projective and descriptive geometry, as is clear from his ''Placita Philosophica'' (1665), ''Euclides Adauctus'' (1671) and ''Architettura Civile'' (1686—not published until 1737), anticipating the work of Gaspard Monge (1746–1818), who is usually credited with the invention of descriptive geometry. Gaspard Monge is usually considered the "father of descriptive geometry" due to his developments in geometric pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Picture Plane
In painting, photography, graphical perspective and descriptive geometry, a picture plane is an image plane located between the "eye point" (or '' oculus'') and the object being viewed and is usually coextensive to the material surface of the work. It is ordinarily a vertical plane perpendicular to the sightline to the object of interest. Features In the technique of graphical perspective the picture plane has several features: :Given are an eye point O (from '' oculus''), a horizontal plane of reference called the ''ground plane'' γ and a picture plane π... The line of intersection of π and γ is called the ''ground line'' and denoted ''GR''. ... the orthogonal projection of O upon π is called the ''principal vanishing point P''...The line through ''P'' parallel to the ground line is called the ''horizon'' HZ The horizon frequently features vanishing points of lines appearing parallel in the foreground. Position The orientation of the picture plane is al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perspective Drawing
Linear or point-projection perspective (from la, perspicere 'to see through') is one of two types of 3D projection, graphical projection perspective in the graphic arts; the other is parallel projection. Linear perspective is an approximate representation, generally on a flat surface, of an image as it is seen by the eye. Perspective drawing is useful for representing a three-dimensional scene in a two-dimensional medium, like paper. The most characteristic features of linear perspective are that objects appear smaller as their distance from the observer increases, and that they are subject to ''foreshortening'', meaning that an object's dimensions along the line of sight appear shorter than its dimensions across the line of sight. All objects will recede to points in the distance, usually along the horizon line, but also above and below the horizon line depending on the view used. Italian Renaissance painters and architects including Masaccio, Paolo Uccello, Piero della Fran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vanishing Point
A vanishing point is a point on the image plane of a perspective drawing where the two-dimensional perspective projections of mutually parallel lines in three-dimensional space appear to converge. When the set of parallel lines is perpendicular to a picture plane, the construction is known as one-point perspective, and their vanishing point corresponds to the oculus, or "eye point", from which the image should be viewed for correct perspective geometry.Kirsti Andersen (2007) ''Geometry of an Art'', p. xxx, Springer, Traditional linear drawings use objects with one to three sets of parallels, defining one to three vanishing points. Italian humanist polymath and architect Leon Battista Alberti first introduced the concept in his treatise on perspective in art, '' De pictura'', written in 1435. Vector notation The vanishing point may also be referred to as the "direction point", as lines having the same directional vector, say ''D'', will have the same vanishing point. Mathem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parallel Projection
In three-dimensional geometry, a parallel projection (or axonometric projection) is a projection of an object in three-dimensional space onto a fixed plane, known as the ''projection plane'' or '' image plane'', where the ''rays'', known as '' lines of sight'' or ''projection lines'', are parallel to each other. It is a basic tool in descriptive geometry. The projection is called '' orthographic'' if the rays are perpendicular (orthogonal) to the image plane, and ''oblique'' or ''skew'' if they are not. Overview A parallel projection is a particular case of ''projection'' in mathematics and ''graphical projection'' in technical drawing. Parallel projections can be seen as the limit of a central or perspective projection, in which the rays pass through a fixed point called the ''center'' or ''viewpoint'', as this point is moved towards infinity. Put differently, a parallel projection corresponds to a perspective projection with an infinite focal length (the distance between th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Image Plane
In 3D computer graphics, the image plane is that plane in the world which is identified with the plane of the display monitor used to view the image that is being rendered. It is also referred to as screen space. If one makes the analogy of taking a photograph to rendering a 3D image, the surface of the film is the image plane. In this case, the viewing transformation is a projection that maps the world onto the image plane. A rectangular region of this plane, called the viewing window or viewport, maps to the monitor. This establishes the mapping between pixels on the monitor and points (or rather, rays) in the 3D world. The plane is not usually an actual geometric object in a 3D scene, but instead is usually a collection of target coordinates or dimensions that are used during the rasterization process so the final output can be displayed as intended on the physical screen. In optics, the image plane is the plane that contains the object's projected image, and lies beyond the ba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Picture Plane
In painting, photography, graphical perspective and descriptive geometry, a picture plane is an image plane located between the "eye point" (or '' oculus'') and the object being viewed and is usually coextensive to the material surface of the work. It is ordinarily a vertical plane perpendicular to the sightline to the object of interest. Features In the technique of graphical perspective the picture plane has several features: :Given are an eye point O (from '' oculus''), a horizontal plane of reference called the ''ground plane'' γ and a picture plane π... The line of intersection of π and γ is called the ''ground line'' and denoted ''GR''. ... the orthogonal projection of O upon π is called the ''principal vanishing point P''...The line through ''P'' parallel to the ground line is called the ''horizon'' HZ The horizon frequently features vanishing points of lines appearing parallel in the foreground. Position The orientation of the picture plane is al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
