computer graphics c version phần 4 pptx

... lines arc then processed through the intersection calculations, which must solve simultaneous circle-line equations Splitting Concave Polygons We can identify a concave polygon by calculating ... Area Clipping (polygons) Curve Clipping Text Clipp~ng Line and polygon clipping routines are standard components of graphics pack- ages, but many packages accommodate curved objects, pa...

Ngày tải lên: 12/08/2014, 11:20

... focusing, deflection of the electron beam can be controlled either with electric fields or with magnetic fields. Cathode-ray tubes are now commonl!. constructed with magnetic deflection coils ... earth's surface by Tom Palmer, Cray Research Inc./NCSC; Chris Landreth, NCSC; and Dave W, NCSC. Pollutant SO, is plotted as a blue surface, acid-rain deposition is a color pla...

Ngày tải lên: 12/08/2014, 11:20

... geometric components of pictures. Additional output primitives that can be used to construct a picture include circles and other conic sections, quadric surfaces, spline curves and surfaces, polygon ... device inter- face methods is given in the Computer Graphics Interface (CGI) system. And the Computer Graphics Metafile (CGM) system specifies standards for archiv- ing and tra...

Ngày tải lên: 12/08/2014, 11:20

... the fill color. This occurs because the algo- rithm checks next pixels both for boundary color and for fill color. Encountering a pixel with the fill color can cause a recursive branch to terminate, ... where text color piramcter tc specifies an allowable color code. We can adj~~st text size by scaling theoverall dimensions (height and width) of characters or by scaling only the ch...

Ngày tải lên: 12/08/2014, 11:20

... r< ;4; r++) for 1c. O; C& lt ;4; c+ +I trnp[r] [cl = a[rl IOI'blO] [cl + alrl Ill'b !I [cl + a[r] [2Ji1[2! Ic] + alr] [3l*b[3] [cl: for (r=O; r< ;4: r*+l for (c= S: cc4; ... orthographic projection is callcd a \hri :Gi13. Engineering and architectr~ral drawings commonly employ these orthographic projritions, because lengths and angles are accurately de...

Ngày tải lên: 12/08/2014, 11:20

... track of which surface section is visible on each scan line. This works only if surfaces do not cut through or otherwise cyclically overlap each other (Fig. 13-11). If any kind of cyclic ... in Chapter 14. 13-1 1 CURVED SURFACES Effective methods for determining visibilit$ for objects with curved surfaces in- clude ray-casting and octree methods. With ray casting, we calculate...

Ngày tải lên: 12/08/2014, 11:20

... Object-Intersection Calculations Raysurface intersection calculations can account for as much as 95 percent of the processing time in a ray tracer. For a scene with many objects, most of the pro- cessing ... to reduce intersection calculations, is to use space-subdivision meth- ods. We can enclose a scene within a cube, then we successively subdivide the cube until each subregion (ce...

Ngày tải lên: 12/08/2014, 11:20

... 36, 341 -44 penod ~c, 337 -41 pmpemes, 335-36 quadratic,338-39, 342 -44 rahonal, 347 surfaces. 344 -45 tenslon parameter, 341 uniform. 336 -44 Buffer, 40 (set elso Frame buffer) Bump function, ... rate, 40 -41 reclo~n,3 94 RCB, 45 shadow-& 43 -44 Gmd-Rom spline, 325 Gvak proimion. 44 3 Cell am, 131 cell&% Cek, 588 Center d projection, 4. 33 Cenlrdl...

Ngày tải lên: 12/08/2014, 11:20

... and science had to rely on expensive and cumbersome equipment, advances in computer technology have made interactive computer graphics a practical tool. Today, we find computer graphics used ... 49 1 Keferences 49 2 Exercises 49 2 lllumination Models 14 and Surface-Rendering Methods 49 4 Visi ble-Su dace Detection Met hods 46 9 Classification of Visible-...

Ngày tải lên: 04/06/2014, 12:01

... changing character coding from one standard to another, as in converting EBCDIC characters (which are used pri- marily with mainframe computers) to ASCII characters. See also ASCII, EBCDIC. file ... ASCII adds capability by allowing for 128 additional characters, such as accented letters, graphics characters, and special symbols. See also ASCII. Extended Binary Coded Decimal Interchan...

Ngày tải lên: 09/08/2014, 09:20