J. D. Foley, A. Van Dam, S. K. Feiner, and J. F. Hughes, Computer Graphics. Addison-Wesley, 1996.  Home/Search   Document Not in Database   Summary   Related Articles   Check

....as possible so that subsequent image matching can be largely 2D in nature. For this reason, the reference orthoimage is projected into the video frame, since the orthoimage already is coregistered to the elevation map. The projection is accomplished via standard texture map based rendering [8]. The digital elevation map is triangulated to yield a 3D mesh. The orthoimage is regarded as a texture, coregistered to the mesh. The mesh vertices are parametrically mapped to the image plane based on the telemetry implied camera projection matrix. Hidden surfaces are removed via Z buffering. ....

J. Foley, A. van Dam, S. Feiner, J. Highes, Computer Graphics, Addison-Wesley, Reading, MA, 1990.

....reflection coefficient K, controls the overall brighiness of the specular higtdight, independent of the brightness of the light sources and the direction of viewing. 2.2 Light Source attenuation Equaltim 1 does nm take init) account light attenuation. practice a formula that does work well [8] is: 1 A i = rain( Cl C2ds c3ds 2 ;I ) 2) A represents the attenuation factor for the light source c is a user defined constant that keeps the denominator from becoming too small when the light is close, c2 and cs are specific to the light source model. The term d, represents the Euclidean ....

....I, cosY(7) where I. is the intensity of the hypothetical light source, p is the refiector s specular exponent and is the angie between L and L . Note that as the value of p increases more of the light is concentrated along L . This model can be generalized to model different types of spot lights [8]. 4. APPLICATION: STILL PICTURES AND VIDEO 4.1 The museum model Our first model consists of the scene placed on a 2D plane and virtual lights that are placed in the 3D space, illuminating the scene. This is similar to the situation where a photograph hanging on a wall is illuminated with spot ....

Foley etal, "Computer Graphics" Addison Wesley 1997

.... V dir)f Given this origin, focal length, and the viewing direction the image plane is defined. Next is the projection of the 3D points of the model onto the image plane. Given a ray between a 3D point and the CP, any standard ray plane intersection routine may be used (for example Foley, et al.[1] or Glassner[2] For this application, the following was used: t = Ro) Gamma ( O) Rd) where Ro is the ray origin (the current 3D point) and Rd is the ray direction defined as Rd = CP Gamma Ro. The value t is the distance along the ray to the intersection point in k Rdk ....

....(2.000,2.000,3.000) 0.05000,0.05000) 0.00000, 0.05303) 2.000, 2.000,3.000) 0.05000, 0.05000) 0.00000, 0.12374) 2.000, 2.000,7.000) 0.02143, 0.02143) 0.03000, 0.07425) 2.000,2.000,7.000) 0.02143,0.02143) 0.03000, 0.03182) 0] 134.00 359.00 269.00 5.000028 0. 059210 8 [ 1] 359.00 315.00 0.00 5.000029 0.059015 7 [ 2] 180.00 224.00 180.00 5.000027 0.058594 10 [ 3] 314.00 181.00 89.00 5.000027 0.058534 5 [ 0] 134.00 359.00 269.0 5.000028 0.059210 13 [ 1] 359.00 315.00 0.00 5.000029 0.059015 17 left= 2.029475, 2.029475,3.044202 ....

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Foley, J. D., Van Dam, A., Feiner, S. K., and Hughes, J. F. Computer Graphics. Addison-Wesley Publishing Company, 1990.

....into its polyhedral faces which are further decomposed into constituent lines. Given an object viewer relationship, these lines are projected into the screen coordinate system and displayed. A good graphics system makes defining these types of geometric relationships simple and intuitive [15]. X Vision provides this functionality and its converse. In addition to stating how a complex object in a particular pose or configuration is decomposed into a list of primitive features, X Vision describes how the pose or attitude is computed given the locations of those primitives. More ....

....written as a product of an upper triangular matrix U and a rotation matrix R(O) as 0 , sin(O) cos(O) The implementation of image warping mirrors this factorization. First, a rotated rectangular area is acquired using an algorithm closely related to Bresenham algorithms for fast line render ing [15]. The resulting buffer can be subsequently scaled and sheared using an optimized bilinear interpolation algorithm. The former is relatively inexpensive, requiring about 2 additions per pixel to implement. The latter is more expensive, requiring 3 multiplies and 6 additions per pixel in our ....

[Article contains additional citation context not shown here]

J.D. Foley, A. van Dam, S.K. Feiner, and j.F. Hughes. Computer' Graphics. Addison Wesley, 1993.

.... polynomial Q = T C (1) where T = t 1] C = ax ay bx by cx cy dx dy with tangentvector Q (t) Q = T C = 3t 2t 10] C (2) Given hermite parameter matrix i = h i x h i y ] p i;1 ] T (3) the corresponding Hermite coefficient matrix C can be derived as [7] = 2 1 1 ;3 ;2 ;1 0 0 1 0 1 0 0 0 We collect all the hermite parameters in state vector H for later use H = 4) When considering the same criteria of usefulness for the contour finding problem as discussed in previous section for the point , polygon and spline based ....

Foley et al., Computer Graphics, AddisonWesley, 1996.

....which are coplanar are joined in one polygon (for this optimization we use a polygon and not a triangle list) V. Shading The normal at the patch center is obtained by estimating a plane Ax By Cz D = 0 through the patch vertices. We use a robust technique, as described in pp. 476 477 of [3]. The coe#cients A, B and C are proportional to the signed areas of the projections of the patch onto the (x, y) x, z) and (y, z) planes, respectively: A, B, C] # 1 2 n # i=1 (z i z i#1 ) y i#1 y i ) 1 2 n # i=1 (z i z i#1 ) x i#1 x i ) 1 2 n # i=1 (y i ....

J.D. Foley, A. van Dam, S.K. Feiner and J.F. Hughes. Computer Graphics. Addison-Wesley, USA, 1997.

....In these cases, simple algorithms are mandatory, especially for basic primitives like lines, circles or ellipses. The algorithm presented in this paper takes advantage of all the previously ideas introduced by the bibliography: it is an incremental algorithm based on the second order differences [Foley92], it uses an error function based on the middle point [Fellner94] it uses the 4 point symmetry and it uses fixed point arithmetic [Fellner93] It uses 32 and 64 bits mantissas. It works with decimal numbers radii. Although the operations works internally with decimal numbers, they use fixed point ....

....When X 2 surpasses (X 0.5) 2 , X is decreased one unit and (X 1.5) 2 is recalculated. For every step, four points are drawn. 5. COMPUTATIONAL COST The aim in this point is to compare the cost given by this fixed point based algorithm to a paradigm like the Middle Point (MP) algorithm [Foley92]. In order to avoid original the MP implementation penalties, an optimised incremental second order differences version was used. This version used temporal variables to avoid redundant calculations and fixed point arithmetic in order to diminish even more the computational cost and to allow the ....

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Foley JD, van Dam A, Feiner SK, Hughes JF (1992) Computer Graphics, Principles And Practice. Addison-Wesley

....cues, achieving balance in terms of complementary colors, and highlighting in terms of complementary colors. Further, little is said about color systems. Readers wanting more information can refer to the newsletter article on color systems (Eddy 1990) and a host of additional resources such as Foley et al. (1990), Durrett (1987) Friedhoff and Benzon (1989) Tufte (1990) and Mante (1972) Color A physics based description of visible light yields an intensity versus wavelength curve over the spectrum of 400 to 700 nanometers. Figure 1 provides an example for one color. Light consists of photons with ....

....color dimension for representing an ordered variable. The use of gray levels is particularly convenient since it provides a brightness dimension without the risk of suggesting other competing orderings based on hue and saturation. The above physics based description of brightness follows that of Foley et al. (1990). However, luminance as a measure of brightness does not tell the whole story. Murch (1987) uses the word brightness to refer to perceptual color changes that are a function of light intensity or roughly speaking, photon rates. As intensity increases it first becomes possible to see something, ....

Foley, J. D., A. van Dam, S. K. Feiner, and J. F. Hughes. (1990), Computer Graphics, Principles and Practice, Second edition, Addison-Wesley Publishing Co. New Yo r k .

....5 discusses the main results of the thesis and presents some ideas for future research and Chapter 6 concludes and summarizes the thesis. 1 2 Chapter 2 Cloud modeling The purpose of a model of an entity is to allow people to visualize and understand the structure or behaviour of the entity [10]. For clouds and gases the model is often implemented as a density function, #(#x) #x # R 3 that, for each point in space, evaluates to the amount of cloud matter that exists at that point. We shall refer to cloud modeling as the task of de ning such a density function. What should be regarded ....

Foley, J. D., van Dam, A., Feiner, S. K., and Hughes, J. F., 1990, Computer Graphics. Principles and Practice. Second edition. AddisonWesley Publishing Company, 1174 pages. ISBN 0-201-12110-7. 41

....1. It is not clear, however, how a Gaussian model of directions should be constructed. In this section various approaches to that problem are reviewed. First note that there are many colour spaces in which the chromaticity and intensity components are explicitly separated, for examples, see [10]. Many common colour spaces, such as the HSV space, are non linear transformations of the original RGB space. Distributions of data in the RGB cube have different shape in these spaces, which can complicate the form of an appropriate SCM. Such spaces are generally intended for intuitive human ....

J. Foley, A. van Dam, S. Feiner, J. Hughes. "Computer Graphics". Addison Wesley. 1990.

....relative to the feature in the image, the image processing operations can presume a standard pose. This makes them simple (and fast) to implement. Acquiring windows at any position and orientation can be implemented quickly by using ideas for fast drawing of lines and boxes borrowed from graphics [2]. In particular, routines for fast acquisition of oriented and scaled windows are provided in the Framework directory. These routines expect a pointer to a region of memory that is the framebuffer for the digitizer. They deliver the closest approximation possible to the requested rectangular ....

....of the intersection point and the orientations of the two subsidiary lines. GILine is a Positionable. It has four state read functions (the analogous write functions follow the convention outlined above) float x( return state[0] float y( return state[1] float angle1( return state[2]; float angle2( return state[3] Members of the queue of tracked objects can be accessed using the pre defined function BasicFeature child(int n) Note that this function is protected, so it cannot be called outside of a CompFeature or one of its derived classes) Since we know that GILine ....

J. Foley, A. v. Dam, S. Feiner, and J. Hughes. Computer Graphics. Addison Wesley, 1993. 17

....improve the user s understanding. In order to correctly represent the occlusion relationships between real and synthetic objects, an AR application needs to consider the depth of the real imagery in the rendering of the synthetic imagery. Synthetic image generation for AR is the same as for VE [Foley90] Of particular interest in this discussion is the depth buffer, or z buffer. This is a standard way that occlusion relationships are established for objects in VE. The way that AR should differ is that the AR system needs to measure or infer depth for the real imagery and compare this data with ....

....that we must apply to our current estimated orientation. We update this portion of the estimate by computing the rotation matrix determined by the incremental rotation parameters in the state. RWC =RWC Rot##; #; ## where Rot##; #; ## is the 3 # 3 rotation matrix determined by the Euler angles [Foley90] Note that the computation of the Jacobian must account for the current total orientation, and thus must reconstruct RWC with the correct inverse for the chosen definition of Euler angles. After this update, the incremental Euler angles #, #,and# are reset to 0.0. Since we ve updated our ....

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Foley, J. D., van Dam, A., Feiner, S. K., and Hughes, J. F. (1990). Computer Graphics, Principles and Practice, Second Edition. Addison-Wesley.

.... fast search over large scale image collections, Smith and Chang proposed Color Sets as an approximation to the Color Histogram representation [Smith and Chang, 1995a, Smith and Chang, 1995b] They first transformed the (R,G,B) color space into a perceptually uniform space, such as (H,S,V) [Foley et al. 1990], and then quantized the transformed color space into M bins. A Color Set is defined as a selection of the colors from the quantized color space. Because Color Set feature vectors are binary, a binary search tree was constructed to allow fast search. The relationship between the proposed Color ....

Foley, J., van Dam, A., Feiner, S., and Hughes, J. (1990). Computer Graphics. Addison Wesley, 2nd edition. 28

....# ### # ## ## # ## ##### ### # ## # (1) The rotation matrix [R G ] describes the rotation of the object relative to the point G. This notation is impractical especially for several sequential transformations. An alternative notation used here is the introduction of homogenous coordinates [1]. For a given point in homogenous coordinates P hom = P x ,P y ,P z ,1) T the transformation is: # ### # ## #### # # ##### (2) P (k 1) point coordinates at time instance t k 1, P (k) point coordinates at time instance t k, M hom ] homogenous transformation matrix The transformation ....

....in the 3 D model. A possible application of such a label image is the detection of regions in an image that are already covered by the reconstructed 3 D model. The software for image synthesis must be able to cope with object occlusions. The implemented virtual cameras us the z buffer algorithm [1] for this purpose. 3.3 Images and Image Primitives Images are represented as matrices. The image classes are implemented as template classes here. For color images or multispectral images a multi bandimage class was designed (class o CPicture T ) Luminance images, depth maps, label images, and ....

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Foley, J. D., van Dam, A., Feiner, S. K., Hughes J. F., "Computer Graphics", Addison --Wesley Publi. Comp. 1990.

....is Jim now He is in the sidewalk on 50th Street. Is Jim wearing his coat Yes. How far away is Jim from a subway entrance A subway entrance is across the street. In order to implement the above, we first need to build an appropriate set of data structures for the simulation. Virtual reality (Foley et al. 1990) systems employ detailed 3 dimensional graphical models of space. In ThoughtTreasure, we have chosen a less detailed representation of space, but a more detailed representation of mental states (such as goals and emotions) of humans in that space. Once the data structures are specified, the ....

Foley, J. D., van Dam, A., Feiner, S. K., and Hughes, J. F. (1990). Computer graphics. Reading, MA: Addison-Wesley.

....of all triangles that intersect the sphere. It is clearly impractical to test all of the triangles for intersection, and in order to make this approach practical, it is necessary to use a data structure that prunes the search space efficiently. As a first step, we use a variation of an oct tree [7] to store the triangles approximating the surface. The basic idea behind an oct tree is to surround a set of spatial data with a bounding cube. Each cube is in turn subdivided into eight disjoint subcubes whose union forms the original cube. This process continues recursively until a cube has ....

J. Foley, A. Van Dam, S. Feiner, and J. Hughes. Computer Graphics. Addison Wesley, New York, 1990.

....the boundary of the domain, i.e. on the convex hull, we connect this edge s midpoint and V to obtain a closed polygon as tile boundary. Figure 7 illustrates the tile construction. We use an inside outside test for simple, closed polygons to determine the set of original data inside a tile, see [10]. Edge Midpoints Triangle Centroids V Figure 7. Tile construction We consider this set of original data for a localized, generalized version of Shepard s method, considering gradient estimates (g x i ; g y i ) at the original data sites x i , to estimate a function ....

J. D. Foley, A. van Dam, S. K. Feiner, and J. F. Hughes. Computer Graphics. Addison Wesley Publishing Company Inc., Reading, MA, second edition, 1990.

.... in the graph are broken; if necessary, information about node clusters is added; nodes are then optimally assigned to discrete levels; edges are routed to reduce edge crossings; nodes are then assigned positions to shorten the total length of all the edges; finally, edges are specified as Bezier[6] curves. Once the layout is done, dot writes it to a file using a user specified output format such as PostScript or GIF. The model we employed to create the MDG of dot uses files as modules, and defines a directed edge between two files if the code in one file refers to a type, variable, function ....

J. D. Foley, A. van Dam, S. K. Feiner, and J. F. Hughes. Computer Graphics. Addison-Wesley, 2nd edition, 1990.

.... bx by cx cy dx dy 3 7 5 with tangent vector Q 0 (t) Q 0 = T 0 Delta C = 3t 2 2t 1 0] Delta C (2) Given hermite parameter matrix H i = h i x h i y ] p i Gamma1 p i i Gamma1 Gamma i ] T (3) the corresponding Hermite coefficient matrix C H i can be derived as [7] C H i = 2 6 4 2 Gamma2 1 1 Gamma3 3 Gamma2 Gamma1 0 0 1 0 1 0 0 0 3 7 5 Delta H i We collect all the hermite parameters in state vector H for later use H = 2 6 6 6 6 6 6 6 4 Gamma 0 p 0 0 : Gamma N p N N 3 7 7 7 7 7 7 7 5 (4) When considering the same ....

Foley et al., Computer Graphics, AddisonWesley, 1996.

....from their 8 neighbouring voxels in the object data set by e.g. trilinear interpolation. Gradients are estimated and shading is calculated according to the scatter function. Finally, the contributions of the rays sample points are composited into the final projection using the over operator [4]. No analytic solution to the volume rendering equation is known. Thus the equation must be solved by use of numeric quadrature. The equation is typically approximated by the rectangle integration formula: I(0; yend ) n Gamma1 X i=0 i Gamma1 Y j=0 e Gammaae(j)4y q(i4y)4y (3) with ....

J. D: Foley, A. van Dam, S. K. Feiner, J. F. Hughes. Computer Graphics. Add. & Wesley, Reading MA, 2nd ed. 1990.

....is applied to the trajectory segments i 2 and (i 1) 1 . In this way the velocity discontinuities are replaced by a polynomial blend. Because of the availability of position and velocity at the end points of each trajectory segment, the interpolation chosen is a third order Hermite polynomial [25]. The Hermite spline is described, following Appendix B, by the polynomials: x(t) a 3 t 3 a 2 t 2 a 1 t a 0 (4.1) y(t) b 3 t 3 b 2 t 2 b 1 t b 0 (4.2) The coefficients a i and b i for the generic segment i are computed by requiring that the polynomials satisfy the ....

....starting point ( x(s 0 ) x 0 y(s 0 ) y 0 (B.2) starting velocity ( v x (s 0 ) v x;0 v y (s 0 ) v y;0 (B.3) ending point ( x(s f ) x f y(s f ) y f (B.4) ending velocity ( v x (s f ) v x;f v y (s f ) v y;f (B.5) B. 6) The Hermite spline can be written in matrix form [25]: X = A M (B.7) Y = B M (B.8) where: X = 0 B B B x(s 0 ) x(s f ) v x (s 0 ) v x (s f ) 1 C C C A Y = 0 B B B y(s 0 ) y(s f ) v y (s 0 ) v y (s f ) 1 C C C A A = a j ) with j = 0; 3 B = b j ) with j = 0; 3 M = 0 B B B m 0;k = s k 0 ; k = 0; 3 m ....

J.D. Foley, A. van Dam, S.K. Feiner, and J.F. Hughes. Computer Graphics. Addison-Wesley Publishing Company, Reading, MA, 1990.

....the controls, we first smooth the trajectory, consisting of a sequence of avoidance maneuvers, using a spline interpolation. First, the path is smoothed by joining the mid points of every consecutive path segments with a third order Hermite spline that matches the slopes of the path segments [13]. Then, the velocity profile along the resulting path is smoothed using a cycloid between the mid points of consecutive velocity segments, given by: v(t) t Gamma sin( t) 2:0 (42) where = 2:0 T , and T is the motion time between the two mid points. Using inverse dynamics, we now compute ....

J.D. Foley, A. van Dam, S.K. Feiner, and J.F. Hughes. Computer Graphics. Addison-Wesley Publishing Company, Reading, MA, 1990.

....Many visualization tools assume that they can interpolate samples in an image or volume to create a continuous function over a region. Examples include marching cubes [Lorensen and Cline, 1987] which tri linearly interpolates sample values to find isosurfaces, and standard image supersampling [Foley et al. 1990], which uses various interpolation techniques to calculate pixel values between known ones. If the assumption that samples can be interpolated is not valid, the visualization algorithms will produce results with artifacts. The assumption is equivalent to assuming that sampled data satisfies the ....

Foley, J. D., van Dam, A., Feiner, S. K., and Hughes, J. F. (1990). Computer Graphics, Principles and Practice, Second Edition. Addison-Wesley, Reading, Massachusetts. Overview of research to date.

....into a rotation matrix and a positive definite upper diagonal matrix. This factoring allows image warping to be implemented in two stages. In the first stage, an image region surrounding the target is acquired and rotated using a variant on standard Bresenham line drawing algorithms [18]. The acquired image is then scaled and sheared using a bilinear interpolation. The resolution of the region is then reduced by averaging neighboring pixels. Spatial and temporal derivatives are computed by applying Prewitt operators on the reduced scale images. More details on this level of the ....

J.D. Foley, A. van Dam, S.K. Feiner, and J.F. Hughes. Computer Graphics. Addison Wesley, 1993.

....to do spatial and non spatial queries and must therefore provide an efficient clustering method, an index in order to speed up searches. 4. 3D GIS VERSUS 3D CAD MODELS 4. 1 An Overview of Main 3D CAD Models CAD models can be sorted in two groups: volume representation and boundary representation (Foley 1990). In the first group, an object is described as a combination of volume primitives (e.g. a cube) This group consists of the decomposition models which comes in two classes: either the model is a constructive one, either it is a descriptive one. Constructive Solid Geometry (CSG) and Primitive ....

....Such an entity representation is a polyhedral one because faces are planes and edges are straight lines: it can only be an approximation for non polyhedral entities. Fig. 5 illustrates a BR. The most common CAD models are CSG and BR. For a complete survey of 3D modelling, we refer the reader to (Foley 1990) or (Cambray 1992) 4.2 Discussion about the Use of CAD Models for 3D GIS In cartographic applications, the decomposition of an entity into faces, edges and vertices is a straight extension of the 2D case: BR seems natural. Unlike volume representation, BR model is easy to manipulate for the ....

Foley, J. D., van Dam, A., Feiner, S., and Hughes, J. (1990), Computer graphics, principles and practice. Publisher: Addison-Wesley Systems Programming Series.

....in more detail. Section 3 explains how S shaped surfaces are dealt with. Section 4 summarizes experimental results and analysis the influence of the view point. 1. 1 Previous Methods There exists a large variety of mathematical descriptions for bended surfaces in the field of computer graphics [3]. Many of them are adapted to the special needs of computer aided design (CAD) One very popular approach is to define the surface of an irregularly shaped object with patches or tiles. If a ray tracer is used for rendering the images, the intersection algorithm considers the tiles as simple ....

J. Foley, A. van Dam, S. Feiner, and J. Hughes. Computer Graphics. Addison--Wesley, 1990.

....meshes this is not trivial. The problem resembles filling of polygons in computer graphics. Running into tails or having holes in the polygon mesh (see figure 11) might cause a simple algorithm to stop before all faces were considered. However, the span and scan line algorithms for polygon filling [FvDFH92] can be applied to this problem. The spans or scan lines ought to be replaced by more generally formed orbits which are drawn in different gray levels in figure 11. 5 Examples The algorithm was implemented and this section shows some results. The implementation works on closed polygon meshes as ....

J. D. Foley, A. van Dam, S. K. Feiner, and J. F. Hughes. Computer Graphics. Addison-Wesley Publishing Company, Bonn, 2nd edition, 1992.

....tracking methods [31] There are several algorithms developed for volume rendering [35, 1] A brief explanation of some of these methods is given below, for the purpose of enlighting the reader in the basic vocabulary and algorithms of the field. For a good introduction to computer graphics, see [27, 28]. 3.1 General Ideas The basic goal of a volume rendering algorithm is to, given an object (usually a 3D dataset) and a view (image plane) generate an image that looks as though the user is looking at that object. There are several issues in generating the image, for instance: ffl What is the ....

Foley, J., van Dam, A., Feiner, S., Hughes, J., Computer Graphics, Addison-Wesley, 1990.

....Y g y g C b = Y b y b (5:3) A colour is usually specified in CIE colour space with a triple (x; y; Y ) These values are used to obtain X and Z as shown in Equation 5.4 below. The values X , Y and Z are then inserted into Equation 5. 5 to obtain the monitor R; G; B values for the given colour [Fol90]. This process assumes the intensity steps produced by the video hardware are linear. X = x y Y Z = 1 Gamma x Gamma y y Y (5:4) 2 6 6 6 6 4 R G B 3 7 7 7 7 5 = 2 6 6 6 6 4 x r C r x g C g x b C b y r C r y g C g y b C b z r C r z g C g z b C b 3 7 7 7 7 5 Gamma1 2 6 6 6 6 4 X Y Z ....

Foley, J.D., A. Van Dam, S.K. Feiner, and J.F. Hughes (1990). Computer Graphics, Principles and Practice. Reading, Massachusetts: Addison-Wesley.

....the introduction. When the observer was located on the left of the object, the back edge of the base of the wedge was also visible (the left line in Figure 9) All these edges were sub pixel positioned using a line antialiasing technique in which each line was given a thickness of one pixel (cf. Foley et al. 1990). Apparatus The images displayed on a high resolution (1280 Theta 1024 pixels) 19in. monitor were controlled by an Indigo (Silicon Graphics, Inc. Mountain View, CA) with an Elan graphics board. Some experimental conditions required the display to be updated according to the observer position ....

Foley, J.D., van Dam, A., Feiner, S.K., & Hughes, J.F., (1990). Computer Graphics, Principles and Practice (2nd ed.). Reading, MA: AddisonWesley Publishing Company, Inc.

....At each node of this tree the information about the mean color, size and location of the underlying object plus all pointers to its sub regions is found. Of special importance is the color distance function, which determines the linking or splitting of regions. A lot of experiments in RGB and HSV [2] color spaces proved that a non linear locus dependent color distance function in the HSV space leads to good segmentations. This function follows the theory of human color perception and color metric (e.g. the darker a color the greater is the allowed difference in hue) The quality of the linked ....

J. D. Foley, A. van Dam, S. K. Feiner, J. F. Hughes, Computer Graphics, Addison-Wesley, 1990.

....of window parameters. The pixel values for all x 2 X are copied into a two dimensional array that is subsequently treated as a rectangular image. Such acquisitions can be implemented extremely efficiently using line drawing and region fill algorithms commonly developed for graphics applications [73]. In the second stage, the windows are processed to locate features. Using feature measurements, a new set of window parameters are computed. These parameters may be modified using external geometric constraints or temporal prediction, and the cycle repeats. We consider an edge segment to be ....

J. Foley, A. van Dam, S. Feiner, and J. Hughes, Computer Graphics. Addison Wesley, 1993.

.... in the graph are broken; if necessary, information about node clusters is added; nodes are then optimally assigned to discrete levels; edges are routed to reduce edge crossings; nodes are then assigned positions to shorten the total length of all the edges; finally, edges are specified as Bezier[6] curves. Once the layout is done, dot writes it to a file using a user specified output format such as PostScript or GIF. The model we employed to create the MDG of dot uses files as modules, and defines a directed edge between two files if the code in one file refers to a type, variable, ....

J. D. Foley, A. van Dam, S. K. Feiner, and J. F. Hughes. Computer Graphics. Addison-Wesley, 2nd edition, 1990.

....into its polyhedral faces which are further decomposed into constituent lines. Given an object viewer relationship, these lines are projected into the screen coordinate system and displayed. A good graphics system makes defining these types of geometric relationships simple and intuitive [15]. X Vision provides this functionality and its converse. In addition to stating how a complex object in a particular pose or configuration is decomposed into a list of primitive features, X Vision describes how the pose or attitude is computed given the locations of those primitives. More ....

....and a rotation matrix R( as A = U R( s x fl 0 s y # cos( Gamma sin( sin( cos( # The implementation of image warping mirrors this factorization. First, a rotated rectangular area is acquired using an algorithm closely related to Bresenham algorithms for fast line rendering [15]. The resulting buffer can be subsequently scaled and sheared using an optimized bilinear interpolation algorithm. The former is relatively inexpensive, requiring about 2 additions per pixel to implement. The latter is more expensive, requiring 3 multiplies and 6 additions per pixel in our ....

[Article contains additional citation context not shown here]

J.D. Foley, A. van Dam, S.K. Feiner, and J.F. Hughes. Computer Graphics. Addison Wesley, 1993.

....of window parameters. The pixel values for all x 2 X are copied into a two dimensional array that is subsequently treated as a rectangular image. Such acquisitions can be implemented extremely efficiently using line drawing and region fill algorithms commonly developed for graphics applications [13]. In the second stage, the windows are processed to locate features. Using feature measurements, a new set of window parameters are computed. These parameters may be modified using external geometric constraints or temporal prediction, and the cycle repeats. We consider an edge segment to be ....

....shuttle s launch pad, Datacube World Review, vol. 2, pp. 1 3, Sept. 1988. Datacube Inc. 4 Dearborn Road, Peabody, MA. 12] A. Castano and S. A. Hutchinson, Visual compliance: Task directed visual servo control, IEEE Transactions on Robotics and Automation, vol. 10, pp. 334 342, June 1994. [13] K. Hashimoto, T. Kimoto, T. Ebine, and H. Kimura, Manipulator control with image based visual servo, in Proc. IEEE Int. Conf. Robotics and Automation, pp. 2267 2272, 1991. 41 Tutorial TT3: Visual Servo Control Hager Hutchinson Corke [14] N. P. Papanikolopoulos and P. K. Khosla, ....

[Article contains additional citation context not shown here]

J.D. Foley, A. van Dam, S.K. Feiner, and J.F. Hughes. Computer Graphics. Addison Wesley, 1993. -- 101 -- Tutorial TT3: Visual Servo Control Hager/Hutchinson/Corke

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J. D. Foley, A. Van Dam, S. K. Feiner, and J. F. Hughes, Computer Graphics. Addison-Wesley, 1996.

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FOLEY, J. D., VAN DAM, A., FEINER, S. K., AND HUGHES, J. F. 1996. Computer graphics (2nd ed. in C): principles and practice. AddisonWesley Longman Publishing Co., Inc.

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J. D. Foley, A. Van Dam, S. K. Feiner, and J. F. Hughes. Computer Graphics. Addison-Wesley, 1996.

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J. Foley, A. van Dam, S. Feiner, J. Hughes, "Computer Graphics", Addison-Wesley Pub. Co., 1990, pp 557-558

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JD Foley, A van Dam, SK Feiner, JF Hughes, Computer Graphics (2nd edition in C). Addison-Wesley, Reading, MA 1996.

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Foley, J. D., van Dam, A., Feiner, S. K., and Hughes, J. F. Computer Graphics:

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J. D. Foley, A. van Dam, S. K. Feiner, and J. F. Hughes, Computer Graphics, Addison-Wesley Publishing Company, 1997.

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J. D. Foley, A. van Dam, S. K. Feiner, and J. F. Hughes. Computer Graphics. Addison-Wesley, 2nd edition, 1990.

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Foley J.D., Van Dam A, Feiner S. K, and Hughes J.F. Computer Graphics. Addison-Wesley, 1990. ( trs complt).

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Foley J. D., van Dam A., Feiner S., Hughes J., 1990, Computer Graphics, Principles and Practice, Addison-Wesley Systems Programming Series, Second edition.

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J. Foley, A. van Dam, S. Feiner & J. Hughes, Computer Graphics, Addison Wesley 1990. 106

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J.D. Foley, A. van Dam, S.K. Feiner, and J.F. Hughes. Computer Graphics. Addison-Wesley, Reading, Massachesetts, 1990.

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J.D. Foley, A. van Dam, S.K. Feiner, and J.F. Hughes. Computer Graphics. Addison-Wesley, Reading, Massachesetts, 1990.

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