Interactive picture construction techniques, Computer Graphics

Explain the interactive picture construction techniques.  interactive picture- construction methods are commonly used in variety of applications, including design and painting packages. These methods provide user with the capability to position objects, to constrain fig. to predefined orientations or alignments, to sketch fig., and to drag objects around the screen. Grids, gravity fields, and rubber band methods are used to aid in positioning and other picture construction operations. The several techniques used for interactive picture construction that are incorporated into graphics packages are:  

(1) Basic positioning methods:- coordinate values supplied by locator input are often used with positioning methods to specify a location for displaying an object or a character string. Coordinate positions are selected interactively with a pointing device, usually by positioning the screen cursor. 

(2) constraints:-A constraint is a rule for altering input coordinates values to produce a specified orientation or alignment of the displayed coordinates. the most common constraint is a horizontal or vertical alignment of straight lines.

(3) Grids:-  Another kind of constraint is a grid of rectangular lines displayed in some part of the screen area. When a grid is used, any input coordinate position is rounded to the nearest intersection of two grid lines.

(4) Gravity field:- When it is needed to connect lines at positions between endpoints, the graphics packages convert any input position near a line to a position on the line. The conversion is accomplished by creating a gravity area around the line. Any related position within the gravity field of line is moved to the nearest position on the line. It illustrated with a shaded boundary around the line.

(5) Rubber Band Methods:- Straight lines can be constructed and positioned using rubber band methods which stretch out a line from a starting position as the screen cursor.

(6) Dragging:- This methods move object into position by dragging them with the screen cursor.

(7) Painting and Drawing:- Cursor drawing options can be provided using standard curve shapes such as circular arcs and splices, or with freehand sketching procedures. Line widths, line styles and other attribute options are also commonly found in painting and drawing packages. 

Posted Date: 7/1/2012 6:32:26 AM | Location : United States

Related Discussions:- Interactive picture construction techniques, Assignment Help, Ask Question on Interactive picture construction techniques, Get Answer, Expert's Help, Interactive picture construction techniques Discussions

Write discussion on Interactive picture construction techniques
Your posts are moderated
Related Questions
Morphing - Key Frame Systems Transformation of object shapes from one form to the other is termed as morphing as short form of metamorphism. This method can be applied to any o

what are the steps involved in 3D transformation

Well you might surprise to what a convex window? In common, on the basis of the shapes the windows are categorized into two classes: i) A Convex shaped windows: Windows of a s

Question 1 Briefly explain the twelve principles of animation Question 2 Explain the methods to set-up pre and post-infinity curves Question 3 What is a model sheet? Exp

Polygon -Rendering Methods Now we will see the application of an illumination model to execute the rendering of standard graphics objects that are formed along with polygonal

Poser - software to generate computer animations Poser: Poser through Curious Labs Creates 3-dimentaional complex models which you can view from any angle, distance o

need help in coding

Question 1 What is JPEG? How do you change the quality of a JPEG image? Question 2 What are the advantages and challenges of virtual classroom? Question 3 What do

Phong Model or Phong Specular Reflection Model It is an empirical model that is not based on physics, although physical observation. Phong observed here for extremely shiny su

Question 1 What is Packet-switching network? Discuss its basic operation Question 2 Briefly describe Jackson's theorem Question 3 List and explain the two popular