Contents
- 1 Can a polygon self intersect?
- 2 How can you fill the polygon with help of scan converting polygon algorithm?
- 3 Which filling algorithm is not appropriate for large polygon?
- 4 How many types of polygon filling algorithms are there?
- 5 How to scan line polygons in OpenGL in C?
- 6 How does the scanline fill algorithm in SCCS work?
Can a polygon self intersect?
A polygon can be self-intersecting, meaning edges cross other edges. (The points of intersection are not vertices.) Regular self-intersecting polygons are identified by a fraction n/m, where n is the number of edges (or vertices) and each vertex is connected to the mth vertex around the circle of vertices.
How can you fill the polygon with help of scan converting polygon algorithm?
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.
- Step 3 − Sort the intersection point in the increasing order of X coordinate i.e. p0,p1, p1,p2, and p2,p3.
Which algorithm is used for filling the interior of a polygon?
Scanline filling is basically filling up of polygons using horizontal lines or scanlines. The purpose of the SLPF algorithm is to fill (color) the interior pixels of a polygon given only the vertices of the figure.
What polygon has equal sides and angles?
regular polygon
A regular polygon has equal sides and equal angles. The most common are regular pentagons (five sides), regular hexagons (six sides), and regular octagons (eight sides). Every other polygon is an irregular polygon.
Which filling algorithm is not appropriate for large polygon?
Boundary fill and flood fill method does not work for large polygons. Whereas scan line fill algorithm does not have these disadvantages. In scan line algorithm rightmost and the left most pixels of the seed pixel are marked and a horizontal line is drawn between them.
How many types of polygon filling algorithms are there?
Pattern-fill the polygon is filled with an arbitrary predefined pattern. 6. Types of Polygons: Convex and Concave Convex Polygon – For any two points P1, P2 inside the polygon, all points on the line segment which connects P1 and P2 are inside the polygon. Concave Polygon – A polygon which is not convex.
How does the scanline fill algorithm work for irregular polygons?
The scanline fill algorithm is an ingenious way of filling in irregular polygons. The algorithm begins with a set of points. Each point is conected to the next, and the line between them is considered to be an edge of the polygon. The points of each edge are adjusted to ensure that the point wih the smaller y value appears first.
When to use only one point in polygon filling?
If both lines intersecting at the vertex are on the same side of the scanline, consider it as two points. If lines intersecting at the vertex are at opposite sides of the scanline, consider it as only one point. Components of Polygon fill: Edge Buckets: It contains an edge’s information.
How to scan line polygons in OpenGL in C?
Scan-line Polygon filling using OPENGL in C Figures on a computer screen can be drawn using polygons. To fill those figures with color, we need to develop some algorithm.There are two famous algorithms for this purpose: Boundary fill and Scanline fill algorithms.
How does the scanline fill algorithm in SCCS work?
The program progresses from the first scanline upward. For each line, any pixels that contain an intersection between this scanline and an edge of the polygon are filled in. Then, the algorithm progresses along the scanline, turning on when it reaches a polygon pixel and turning off when it reaches another one, all the way across the scanline.
https://www.youtube.com/watch?v=PZZA92YS9do