coordinate system
- Computer Graphics: Coordinate Systems
- Coordinate System
- coordinate system - stony brooks
- World coordinate system - how does it work in FANUC ?
- Coordinate Systems and Transformations
- Types of Coordinate Systems
- Matrix Representation of Transformations
- Global and Local Transformations
- Coordinate Systems
- World coordinates, Normalised device coordinates and device coordinates
- Introduction to Computer Graphics (Lecture 4): Coordinates and transformations
- Coordinate Systems
- Coordinate System
- Changing Coordinate Frame
- coordinate system transformation
- coordinate system -indiana
- coordinate system - stony brooks
- 2D and 3D Viewing Transformations
- world coordinate system
- Coordinate Representations in Computer Graphics
- Transformations From World To Viewing Coordinate
- Coordinate System
- Computer Graphics - Week 3
good clear description
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World coordinate system - how does it work in FANUC ?
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GDI+ provides a world transformation and a page transformation so that you can transform (rotate, scale, translate, and so on) the items you draw. The two transformations also allow you to work in a variety of coordinate systems.
GDI+ uses three coordinate spaces: world, page, and device.
World coordinates are the coordinates used to model a particular graphic world and are the coordinates you pass to methods in the .NET Framework.
Page coordinates refer to the coordinate system used by a drawing surface, such as a form or control.
Device coordinates are the coordinates used by the physical device being drawn on, such as a screen or sheet of paper.
When you make the call myGraphics.DrawLine(myPen, 0, 0, 160, 80), the points that you pass to the DrawLine method—(0, 0) and (160, 80)—are in the world coordinate space. Before GDI+ can draw the line on the screen, the coordinates pass through a sequence of transformations. One transformation, called the world transformation, converts world coordinates to page coordinates, and another transformation, called the page transformation, converts page coordinates to device coordinates.
An m×n matrix is a set of numbers arranged in m rows and n columns. The following illustration shows several matrices.
A global transformation is a transformation that applies to every item drawn by a given Graphics object. In contrast, a local transformation is a transformation that applies to a specific item to be drawn.
Theoretic Papers
Coordinate System "Handedness"
detailed answers..
Many slides courtesy past instructors of 6.837, notably Fredo Durand and Barbara Cutler.
The World Coordinate System We have learned that points' and vectors' coordinates relate to the origin of a Cartesian coordinate system defined by three perpendicular unit vectors (that make up a basis). We have also explained that we can create as many coordinate systems as we want and that points and vectors have unique coordinates within each of these coordinate systems. However, in most 3d applications, each type of coordinate system is defined with respect to a master coordinate system called the world coordinate system. It represents the origin and the main x-, y-, and z-axes defined by all other coordinate systems. The world coordinate system is the most important of all the different coordinate systems in the rendering pipeline. These include the object, local (used in shading), camera, and screen coordinate systems. We will explain all of these as we go along.
best description I ever see...
Often in computer graphics we will find it useful to describe locations with respect to a particular coordinate frame. The most common scenario is describing the vertices that make up an object with respect to that object's coordinate frame
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2D and 3D Viewing Transformations
world coordinate system
With few exceptions, general graphics packages are designed to be used with Cartesian coordinate specifications. If coordinate values for a picture are specified in some other reference frame (spherical, hyperbolic, etc.), they must be converted to Cartesian coordinates before they can be input to the graphics package. Special-purpose packages may allow use of other coordinate frames that are appropriate to the application.
In general; several different Cartesian reference frames are used to construct and display a scene. We can construct the shape of individual objects, such as trees or furniture, in a scene within separate coordinate reference frames called modeling coordinates (MC), or sometimes local coordinates or master coordinates.
Once individual object shapes have been specified, we can place the objects into appropriate positions within the scene using a reference frame called world coordinates (WC).
Finally, the world-coordinate description of the scene is transferred to one or more output-device reference frames for display. These display coordinate systems are referred to as device coordinates (DC) or, screen coordinates in the case of a video monitor.
Modeling and world-coordinate definitions allow us to set any convenient floating-point or integer dimensions without being hampered by the constraints of a particular output device. For some scenes, we might want to specify object dimensions in fractions of a foot, while for other applications we might want to use millimeters, kilometers, or light-years.
Generally, a graphics system first converts world-coordinate positions to normalized device coordinates (NDC), in the range from 0 to 1, before final conversion to specific device coordinates. This makes the system independent of the various devices that might be used at a particular workstation. Figure 2-65 illustrates the sequence of co-ordinate transformations from modeling coordinates to device co-ordinates for a two-dimensional application. An initial modeling-coordinate position (Xmc, Ymc) in this illustration is transferred to a device coordinate position (Xdc, Ydc) with the sequence:
The modeling and world-coordinate positions in this transformation can be any floating-point values; normalized coordinates satisfy the inequalities: 0 ≤ Xndc ≤ 1, 0 ≤ Yndc ≤ 1; and the device coordinates Xdc and Ydc are integers within the range (0, 0) to (Xmax, Ymax) for a particular output device. To accommodate differences in scales and aspect ratios, normalized coordinates are mapped into a square area of the output device so that proper proportions are maintained.
Transformations From World To Viewing Coordinate
analyzes the world2ndc matrix we have worked with in all of the tutorials
Computer Graphics - Week 3
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