Knowledge in Computer Graphics
Computer Graphics-3-D Coordinate Spaces
Here we learn about some of the concepts of Computer Graphics: 3-D Coordinate Spaces Translations In 3-D Scaling In 3-D Rotations In 3-D
yash sharma
Computers as Superhighway
This is the space where I have mentioned when the computers were introduced with the internet.
Saumya Shah
FUNDAMENTAL OF COMPUTERS (OUTPUT DEVICES) (First semester notes) Chapter-1 (Part-2) Makhanlal chaturvedi national University,Bhopal
(Part-2)IN This, There is a chapter first of COMPUTER FUNDAMENTAL Subject Part-1 named INTRODUCTION OF COMPUTER Makhanlal Chaturvedi national journalism and communication University, Bhopal. There is a very important note oF Fundamental computers For BCA first semester Students. Share with your friends and help them to learn Fundamental of Computers. There are Five subjects in BCA first semester .
Piyush Gupta
All ABOUT PRINTER IN EASY LANGAUGE (BCA FIRST SEMESTER NOTES)
IN This, There is a chapter first of COMPUTER FUNDAMENTAL Subject named INTRODUCTION OF COMPUTER Makhanlal Chaturvedi national journalism and communication University, Bhopal. There is a very important note oF Fundamental computers For BCA first semester Students. Share with your friends and help them to learn Fundamental of Computers. There are Five subjects in BCA first semester . "HERE WE DISCUSSED A VERY IMPORTANT TOPIC NAMED ALL ABOUT PRINTER".
FUNDAMENTAL OF COMPUTERS (CONCEPT OF COMPUTER) (First semester notes) Chapter-1 (Part-3) Makhanlal chaturvedi national University,Bhopal
(Part-3) IN This, There is a chapter first of COMPUTER FUNDAMENTAL Subject Part-3 named INTRODUCTION OF COMPUTER Makhanlal Chaturvedi national journalism and communication University, Bhopal. There is a very important note oF Fundamental computers For BCA first semester Students. Share with your friends and help them to learn Fundamental of Computers. There are Five subjects in BCA first semester .
FUNDAMENTAL OF COMPUTERS (OPERATING SYSTEM) (First semester notes) Chapter-1 (Part-4) Makhanlal chaturvedi national University,Bhopal
(Part-4) IN This, There is a chapter first of COMPUTER FUNDAMENTAL Subject Part-4 named INTRODUCTION OF COMPUTER Makhanlal Chaturvedi national journalism and communication University, Bhopal. There is a very important note oF Fundamental computers For BCA first semester Students. Share with your friends and help them to learn Fundamental of Computers. There are Five subjects in BCA first semester .
INTRODUCTION OF COMPUTER (First semester notes) Chapter-1 (Part-7) Makhanlal chaturvedi national University,Bhopal
(Part-8) IN This, There is a chapter first of COMPUTER FUNDAMENTAL Subject Part-8 named INTRODUCTION OF COMPUTER Makhanlal Chaturvedi national journalism and communication University, Bhopal. There is a very important note oF Fundamental computers For BCA first semester Students. Share with your friends and help them to learn Fundamental of Computers. There are Five subjects in BCA first semester .
NUMBER SYSTEM (First semester notes) Chapter-2 (Part-1) Makhanlal chaturvedi national University,Bhopal
(Part-1) IN This, There is a chapter SECOND of COMPUTER FUNDAMENTAL Subject Part-1 named NUMBER SYSTEM Makhanlal Chaturvedi national journalism and communication University, Bhopal. There is a very important note oF Fundamental computers For BCA first semester Students. Share with your friends and help them to learn Fundamental of Computers. There are Five subjects in BCA first semester . NUMBER SYSTEM
TYPES OF NUMBER SYSTEM (First semester notes) Chapter-2 (Part-2) Makhanlal chaturvedi national University,Bhopal
(Part-1) IN This, There is a chapter SECOND of COMPUTER FUNDAMENTAL Subject Part-1 named NUMBER SYSTEM Makhanlal Chaturvedi national journalism and communication University, Bhopal. There is a very important note oF Fundamental computers For BCA first semester Students. Share with your friends and help them to learn Fundamental of Computers. There are Five subjects in BCA first semester . NUMBER SYSTEM
Clipping in CG
Clipping:When we have to display a large portion of the picture, then not only scaling & translation is necessary, the visible part of picture is also identified. This process is not easy. Certain parts of the image are inside, while others are partially inside. The lines or elements which are partially visible will be omitted.For deciding the visible and invisible portion, a particular process called clipping is used. Clipping determines each element into the visible and invisible portion. Visible portion is selected. An invisible portion is discarded.Types of Lines:Lines are of three types:Visible: A line or lines entirely inside the window is considered visibleInvisible: A line entirely outside the window is considered invisibleClipped: A line partially inside the window and partially outside is clipped. For clipping point of intersection of a line with the window is determined.Clipping can be applied through hardware as well as software. In some computers, hardware devices automatically do work of clipping. In a system where hardware clipping is not available software clipping applied.Following figure show before and after clipping
Dushyant Jodha
Application of Clipping
Applications of clipping:It will extract part we desire.For identifying the visible and invisible area in the 3D object.For creating objects using solid modeling.For drawing operations.Operations related to the pointing of an object.For deleting, copying, moving part of an object.Clipping can be applied to world co-ordinates. The contents inside the window will be mapped to device co-ordinates. Another alternative is a complete world co-ordinates picture is assigned to device co-ordinates, and then clipping of viewport boundaries is done.Types of Clipping:Point ClippingLine ClippingArea Clipping (Polygon)Curve ClippingText ClippingExterior Clipping
2-D VIEWING AND CLIPPING
INTRODUCTION In the earlier two units of this block, we discussed the basic components of computer graphics, i.e., the software and hardware used for graphic systems along with the graphic primitives used to create graphic images. Now, we are in a position to discuss technicalities related to the display of any graphic primitive or image. Let us begin with, the concept of clipping, for both point and line clipping, followed by the concerned algorithms used to perform line clipping. We shall then examine the concept and algorithm related to polygon clipping, and end with a discussion on window to viewport transformations. Clipping may be described as the procedure that identifies the portions of a picture lie inside the region, and therefore, should be drawn or, outside the specified region, and hence, not to be drawn. The algorithms that perform the job of clipping are called clipping algorithms there are various types, such as: • Point Clipping • Line Clipping • Polygon Clipping • Text Clipping • Curve Clipping Further, there are a wide variety of algorithms that are designed to perform certain types of clipping operations, some of them which will be discussed in unit. Line Clipping Algorithms: • Cohen Sutherland Line Clippings • Cyrus-Beck Line Clipping Algorithm Polygon or Area Clipping Algorithm • Sutherland-Hodgman Algorithm There are various other algorithms such as, Liang – Barsky Line clipping, Weiler-Atherton Polygon Clipping, that are quite efficient in performing the task of clipping images. But, we will restrict our discussion to the clipping algorithms mentioned earlier. Before going into the details of point clipping, let us look at some basic terminologies used in the field of clipping, such as, window and viewport. Window may be described as the world coordinate area selected for display. 71 Raster Graphics and Clipping Viewport may be described as the area on a display device on which the window is mapped. So, it is the window that specifies what is to be shown or displayed whereas viewport specifies where it is to be shown or displayed. Specifying these two coordinates, i.e., window and viewport coordinates and then the transformation from window to viewport coordinates is very essential from the point of view of clipping. Note: • Assumption: That the window and viewport are rectangular. Then only, by specifying the maximum and the minimum coordinates i.e., (Xwmax, Ywmax) and (Xwmin, Ywmin) we can describe the size of the overall window or viewport. • Window and viewport are not restricted to only rectangular shapes they could be of any other shape (Convex or Concave or both). For better understanding of the clipping concept refer to Figure 1: 72 Figure 1: Clipping alongwith Viewing Transformation through rectangular window and viewport 3.2 OBJECTIVES After going though this unit, you should be able to: • explain the concept of clipping, • examine how line clipping is performed, • understand and implement the algorithms that work behind the concept of line clipping, • explain how polygon clipping is performed, • understand and implement the algorithms that work behind the concept of polygon clipping, and • describe window to viewport transformation. 3.3 POINT CLIPPING Point clipping is the technique related to proper display of points in the scene, although, this type of clipping is used less frequently in comparison to other types, i.e., line and polygon clipping. But, in some situations, e.g., the scenes which involve particle movements such as explosion, dust etc., it is quite useful. For the sake of simplicity, let us assume that the clip window is rectangular in shape. So, the minimum and maximum coordinate value, i.e., (Xwmax, Ywmax) and (Xwmin, Ywmin) Wxmin Wxmax Vxmin Vxmax Wymin Wymax Vyma Vymin x Window Viewport World Coordinates Device Coordinates Object Clipped Image of Object 2-D Viewing and Clipping are sufficient to specify window size, and any point (X,Y), which can be shown or displayed should satisfy the following inequalities. Otherwise, the point will not be visible. Thus, the point will be clipped or not can be decided on the basis of following inequalities. Ywmax Xwmin ≤ X ≤ Xwmax Ywmin ≤ Y ≤ Ywmax Ywmin Xwmin Xwmax Figure 2: Point Clipping It is to be noted that (Xwmax, Ywmax) and (Xwmin, Ywmin) can be either world coordinate window boundary or viewport boundary. Further, if any one of these four inequalities is not satisfied, then the point is clipped (not saved for display).