The Flood Fill Algorithm fills a connected region on a raster display by replacing all pixels that share the same original colour as the seed pixel with a new fill colour. Unlike the Boundary Fill Algorithm — which stops at a specific boundary colour — Flood Fill continues spreading in all directions as long as the pixel matches the original seed colour. It is the underlying technique used by the “Paint Bucket” tool in image editors.
The Digital Differential Analyzer (DDA) algorithm is one of the simplest line-drawing algorithms in computer graphics. It is an incremental method that determines intermediate points between two given endpoints of a line. In this blog post, we will explore the DDA algorithm, understand its working, and implement it using C++. What is the DDA Algorithm? The DDA (Digital Differential Analyzer) algorithm is a rasterization algorithm used to draw lines on a pixel-based display. It works by calculating the intermediate points that form a straight line between two given points and plotting them sequentially. The algorithm uses floating-point arithmetic to incrementally determine the next pixel position. Steps of the DDA Algorithm: Calculate the change in x (dx) and y (dy) between the starting and ending points. Determine the number of steps required for the line. This is the greater value between dx and dy. Compute the increment values dx/steps and dy/steps to determine how much x and y should increase per step. Start from the initial point and iteratively plot the next points by adding the increment values. Stop when the endpoint is reached. C++ Implementation of DDA Algorithm Here is a simple C++ program to implement the DDA line drawing algorithm using the graphics.h library:
The Cohen-Sutherland Line Clipping Algorithm is one of the most widely used algorithms in computer graphics for clipping line segments against a rectangular viewport. It works by assigning a 4-bit region code to each endpoint of a line to quickly determine whether the line is fully inside the window, fully outside, or needs to be clipped. The algorithm avoids expensive intersection calculations whenever possible, making it very efficient for real-time rendering pipelines.
Character Generation by the Bitmap Method is a fundamental technique in computer graphics for rendering text or custom symbols on a raster display. A character is represented as a two-dimensional binary (or integer) grid — called a bitmap — where each cell in the grid corresponds to one pixel. A 1 (or any non-zero value) means the pixel should be drawn; a 0 means it should be left blank. This method is used in early video games, embedded displays, and any system that needs custom pixel-perfect fonts.
This post demonstrates how to sort an array of integers using inline assembly in C++. We use basic comparison and swap logic in assembly embedded within a C++ program. #include<iostream.h> #include<conio.h> void main() { int a[5], x, y; int i, j; cout << "\n Enter 5 Numbers:"; for(i = 0; i < 5; i++) { cin >> a[i]; } //Sorting for(i = 0; i < 4; i++) { for(j = 0; j < 4; j++) { x = a[j]; y = a[j + 1]; asm { mov ax, x mov bx, y cmp ax, bx jge nxt mov cx, ax mov ax, bx mov bx, cx mov x, ax mov y, bx } nxt: a[j] = x; a[j + 1] = y; } } cout << "\n Sorted Array:"; for(i = 0; i < 5; i++) cout << a[i] << " "; getch(); }
Bresenham's circle algorithm is an efficient way to draw a circle using only integer calculations. It eliminates the need for floating-point arithmetic and is widely used in computer graphics. Below is the implementation of Bresenham's circle drawing algorithm using C++ and the graphics.h library. This program takes user input for the circle's center and radius, then uses the algorithm to plot the circle.
The Boundary Fill Algorithm is a region-filling technique used in computer graphics to fill a connected area with a new colour. Starting from a seed pixel inside the shape, the algorithm recursively colours every neighbouring pixel as long as it does not match the defined boundary colour and has not already been coloured with the new fill colour. It supports 8-connected filling, meaning it spreads to all eight surrounding pixels — including diagonals.
Bresenham's Line Algorithm is one of the most fundamental algorithms in computer graphics. It determines the set of pixels that most closely approximate a straight line between two given endpoints on a raster display. The key advantage of Bresenham's algorithm over simpler approaches is that it uses only integer arithmetic — no floating-point multiplication or division — making it extremely fast for hardware and software rendering alike.
2-D Transformations are fundamental operations in computer graphics that change the position, size, or orientation of geometric objects on a 2-D plane. The three basic transformations are Translation (moving an object), Scaling (resizing an object), and Rotation (rotating an object about the origin). This C++ program implements all three transformations on a line segment entered by the user and renders the transformed result using the Turbo C++ graphics.h library.
The Tower of Hanoi is a classic mathematical puzzle that elegantly demonstrates the power of recursion. It consists of three rods (pegs) and a number of disks of different sizes that can slide onto any rod. The puzzle begins with all disks stacked in ascending size order on one rod (smallest on top) and the goal is to move the entire stack to another rod. Three rules must be followed: Only one disk may be moved at a time. A disk may only be moved if it is the uppermost disk on its rod. No disk may be placed on top of a smaller disk. The minimum number of moves required to solve the puzzle with n disks is 2n − 1. For 3 disks, that's 7 moves; for 10 disks, 1023 moves.