What is scan line algorithm explain?

It is an image space algorithm. It processes one line at a time rather than one pixel at a time. It uses the concept area of coherence. This algorithm records edge list, active edge list.

What is scan line polygon algorithm?

This algorithm lines interior points of a polygon on the scan line and these points are done on or off according to requirement. The polygon is filled with various colors by coloring various pixels. In above figure polygon and a line cutting polygon in shown.

What are advantages of scan line fill algorithm?

Advantage of scan-line fill: It does fill in the same order as rendering, and so can be pipelined. Scan Line Fill: What happens at edge end-point? Edge endpoint is duplicated. In other words, when a scan line intersects an edge endpoint, it intersects two edges.

What is rasterization and Scan Conversion?

The process of representing continuous graphics object as a collection of discrete pixels by identifying their locations and setting them on is called Scan Conversion. The process of determining which pixels will provide the best approximation to the desired line is properly known as rasterization.

How many tables are used in scan line method?

In scan line algorithm we create two tables, first one is known as polygon table which is different for each and every polygon and the other one is known as edge table.

What is scan line polygon fill algorithm explain the algorithm with the help of an example use appropriate diagrams wherever necessary?

Scan Line Algorithm Step 1 − Find out the Ymin and Ymax from the given polygon. Step 2 − ScanLine intersects with each edge of the polygon from Ymin to Ymax. Name each intersection point of the polygon. As per the figure shown above, they are named as p0, p1, p2, p3.

What is scan line polygon fill algorithm explain the algorithm with the help of an example?

How many tables are in scan line method?

Two
Scan-Line Method Two important tables, edge table and polygon table, are maintained for this.

What is advantage and disadvantage of scan line filling algorithm?

The advantages of Scan line algorithm are as follows:= 1) It takes advantage of coherence resulting in fast algorithm. 2) It does require as much storage as depth buffer. 3) It only draws visible pixels. 4) This algorithm is common in software.

Is rasterization and scan conversion same?

In Raster Graphics, we create a discretized image of the whole screen onto the frame buffer first. The image is scanned automatically onto the display periodically. This step is called Scan Conversion or Rasterization. The 3D point has been transformed to its screen coordinates (u, v).

What are two types of scan conversion?

There are two distinct methods for changing a picture’s data rate: Analog Methods (Non retentive, memory-less or real time method) This conversion is done using large numbers of delay cells and is appropriate for analog video. It may also be performed using a specialized scan converter vacuum tube.

What is z-buffer algorithm?

It is also called a Depth Buffer Algorithm. Depth buffer algorithm is simplest image space algorithm. For each pixel on the display screen, we keep a record of the depth of an object within the pixel that lies closest to the observer.

In which algorithm the active edge list is used?

Q.	Active edge table is used in following algorithm
B.	region fill
C.	scan line
D.	edge fill
Answer» c. scan line

Which algorithm is used to fill polygon?

Scan Line Algorithm
Scan Line Algorithm The polygon is filled with colours in between the intersecting pairs. The practical working of the algorithm is shown below: Step 1 − Find out the Ymin and Ymax from the given polygon. Step 2 – From each edge of the polygon from Ymin to Ymax, all the egdes are intersected by Scanline.

How many types of polygon filling algorithm are?

Three types of polygon are recognized, figure (1): convex, concave, and complex.

What is rasterization computer graphics?

Rasterization (or rasterisation) is the task of taking an image described in a vector graphics format (shapes) and converting it into a raster image (a series of pixels, dots or lines, which, when displayed together, create the image which was represented via shapes).

What is DDA scan conversion algorithm?

The digital differential analyzer is a scan conversion algorithm based on calculation either y or x using the following equations: y = m * x. x = y / m. Sample the line at unit intervals in one coordinate and determine corresponding integer values nearest the line path for the coordinates.

What are the 4 steps of Warnock’s algorithm?

Fig.3.5. Warnock algorithm

• Initialize the region.
• Generate list of polygons by sorting them with their z values.
• Remove polygons which are outside the area.
• Identify relationship of each polygon.
• Execute visibility decision analysis:
• If none of above is correct then subdivide the area and Go to Step 2.

Which algorithm is used to draw a line?

Bresenham’s line algorithm is a line drawing algorithm that determines the points of an n-dimensional raster that should be selected in order to form a close approximation to a straight line between two points.

Do I need a rasterizer on every scanline?

This check must be done on every scanline, not just at events, but in the vast majority of cases no swapping will be necessary, so the cost of this check is low. As I mentioned in class, manipulations to the edge tables typically represent a small fraction of the cost of a rasterizer.

What are the different raster graphics algorithms?

Raster Graphics Algorithms „scan conversion „Line rasterization „Bresenham’s Midpoint line algorithm „Midpoint circle algorithm „Midpoint ellipse algorithm and more „Filled primitives Sept 29-Oct 1, 2003 CMPT-361 : Hamid Younesy 2

What is the purpose of the intersecting line in a scan?

As each scan line is processed, this line will intersect many surfaces. The intersecting line will determine which surface is visible. Depth calculation for each surface is done.

What is the edge list algorithm in image processing?

It is an image space algorithm. It processes one line at a time rather than one pixel at a time. It uses the concept area of coherence. This algorithm records edge list, active edge list. So accurate bookkeeping is necessary. The edge list or edge table contains the coordinate of two endpoints.