111 lines
2.6 KiB
C++
111 lines
2.6 KiB
C++
/*
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Problem Statement: a) Write C++ program to draw the following pattern. Use DDA line and Bresenham's circle drawing algorithm. Apply the concept of encapsulation.
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Code from Computer Graphics (SPPU - Second Year - Computer Engineering - Content) repository on KSKA Git: https://git.kska.io/sppu-se-comp-codes/CG
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*/
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// BEGINNING OF CODE
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#include <iostream>
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#include <graphics.h>
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#include <math.h>
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using namespace std;
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void bresenhamCircle(int xcord, int ycord, int rad) {
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// function to create circle using Bresenham algorithm
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int dec, x, y;
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dec = 3-2*rad; // dec is the decision parameter
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x = 0;
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y = rad; // set y equals to radius
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while (y >= x) {
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putpixel(xcord+x, ycord+y, 15); // bottom right
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putpixel(xcord+y, ycord+x, 15); // right side
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putpixel(xcord+y, ycord-x, 15); // right up
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putpixel(xcord+x, ycord-y, 15); // top
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putpixel(xcord-x, ycord-y, 15); // left top
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putpixel(xcord-y, ycord-x, 15); // left side
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putpixel(xcord-y, ycord+x, 15); // left bottom
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putpixel(xcord-x, ycord+y, 15); // bottom
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x++;
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// note: 15 is the colour, instead you can also put WHITE, RED, GREEN, etc.
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// decision paramter
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if (dec > 0 ) {
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y--;
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dec = dec+4*(x-y)+10;
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}
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else {
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dec = dec+4*x+6;
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}
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// delay(10); // optional delay to watch the circle being made
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}
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}
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void ddaLine(float x1, float y1, float x2, float y2) {
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// DDA line drawing algorithm (will be used for triangle)
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float dx, dy, steps, xinc, yinc, x, y;
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dx = abs(x2-x1);
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dy = abs(y2-y1);
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if (dx>dy) {
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steps = dx;
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}
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else {
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steps = dy;
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}
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xinc = (x2-x1)/steps;
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yinc = (y2-y1)/steps;
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x = x1;
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y = y1;
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putpixel(round(x), round(y), 15);
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for (int i=0; i<steps; i++) {
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x = x + xinc;
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y = y + yinc;
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putpixel(round(x), round(y), 15);
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}
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}
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int main() {
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float x1, y1, x2, y2, x3; // variables to store line coordinates
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int x, y, r; // variables to store circle coordinates
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cout<<endl<<"Enter coordinates:";
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cout<<endl<<"Enter value for X1:\t";
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cin>>x1;
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cout<<endl<<"Enter value for Y1:\t";
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cin>>y1;
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cout<<endl<<"Enter value for X2:\t";
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cin>>x2;
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// calculating values for x3 and y2 for triangle
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x3 = (x2+x1)/2;
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y2 = y1 - sqrt(pow((x2-x1), 2) - pow((x2-x1)/2, 2));
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// initializing graphics window
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int gd=DETECT, gm;
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initgraph(&gd, &gm, NULL);
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// make triangle
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ddaLine(x1, y1, x2, y1);
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ddaLine(x2, y1, x3, y2);
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ddaLine(x3, y2, x1, y1);
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// make inner circle
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x = x3;
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y = y2+2*(y1-y2)/3;
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r = (y1-y2)/3;
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bresenhamCircle(x,y,r);
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// make outer circle
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r = 2*(y1-y2)/3; // instead you can also use "r=2*r", it's the same
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bresenhamCircle(x,y,r);
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delay(50000);
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closegraph();
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return 0;
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}
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// END OF CODE
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