Bjarne Stroustrup “Programming Principles and Practice Using C++”
Chapter 13 Exercise 15
Using GUI library called FLTK (Fast Light Tool Kit, “full tick”).
Output:
[code language=”cpp”]
// Philipp Siedler
// Bjarne Stroustrup’s PP
// Chapter 13 Exercise 15
#define _USE_MATH_DEFINES
#include "Simple_window.h"
#include "Graph.h"
#include <cmath>
using namespace Graph_lib;
ostream& operator<<(ostream& out, Point& a) {
out << "(" << a.x << "," << a.y << ")";
return out;
}
Point operator-(Point& p1, Point& p2) {
Point p3 = Point(p1.x – p2.x, p1.y – p2.y);
return p3;
}
Point operator+(Point& p1, Point& p2) {
Point p3 = Point(p1.x + p2.x, p1.y + p2.y);
return p3;
}
double pointVecMag(Point vec) {
return sqrt(pow(vec.x, 2) + pow(vec.y, 2));;
}
struct Regular_triangle : Closed_polyline
{
Regular_triangle(Point origin, int edge, int height, Fl_Color linecolor)
: o(origin), e(edge), h(height), lc(linecolor)
{
generate_points();
};
void generate_points();
void rotate_triangle(double rad);
void draw_lines() const;
private:
Point o;
int e;
int h;
Fl_Color lc;
};
void Regular_triangle::generate_points()
{
add(o);
add(Point(o.x + e, o.y));
add(Point(o.x + e / 2, o.y – h));
};
void Regular_triangle::draw_lines() const
{
fl_color(lc);
Closed_polyline::draw_lines();
};
void Regular_triangle::rotate_triangle(double rad)
{
Point origin_Pt1 = Regular_triangle::point(0) – Regular_triangle::point(2);
Point origin_Pt2 = Regular_triangle::point(1) – Regular_triangle::point(2);
Point rotated_Pt1 = Point(cos(rad) * origin_Pt1.x – sin(rad) * origin_Pt1.y, sin(rad) * origin_Pt1.x + cos(rad) * origin_Pt1.y);
Point rotated_Pt2 = Point(cos(rad) * origin_Pt2.x – sin(rad) * origin_Pt2.y, sin(rad) * origin_Pt2.x + cos(rad) * origin_Pt2.y);
Regular_triangle::set_point(0, rotated_Pt1 + Regular_triangle::point(2));
Regular_triangle::set_point(1, rotated_Pt2 + Regular_triangle::point(2));
};
struct rt_tiling : Shape
{
rt_tiling(Point basepoint, int edge, int height, int xcount, int ycount)
:bp(basepoint), e(edge), h(height)
{
xc = (xcount == 0) ? 1 : xcount;
yc = (ycount == 0) ? 1 : ycount;
generate_pts();
}
void draw_lines() const;
void generate_pts();
private:
vector<Point> pts;
Point bp;
int e;
int h;
int xc;
int yc;
};
void rt_tiling::generate_pts() {
for (int i = 0; i < yc; i++) {
for (int j = 0; j < xc; j++) {
if (i % 2 == 0) {
if (j % 2 == 0) {
pts.push_back(Point(bp.x + (e / 2) * j, bp.y + h * i));
}
else {
pts.push_back(Point(bp.x + (e / 2) * j, bp.y + h * i + h));
}
}
else {
if (j % 2 == 0) {
pts.push_back(Point(bp.x + (e / 2) * j, bp.y + h * i + h));
}
else {
pts.push_back(Point(bp.x + (e / 2) * j, bp.y + h * i));
}
}
}
}
}
void rt_tiling::draw_lines() const
{
for (int i = 0; i < xc; i++) {
for (int j = 0; j < yc; j++) {
Regular_triangle rt(pts[i + j * xc], e, h, Color::red);
if (j % 2 == 0) {
if (i % 2 != 0 && j % 2 == 0) {
rt.rotate_triangle(M_PI);
}
}
else {
if (i % 2 == 0 && j % 2 != 0) {
rt.rotate_triangle(M_PI);
}
}
rt.draw_lines();
}
}
};
int main()
try
{
Point tl(100, 100);
Simple_window win(tl, 720, 400, "Simple Window");
Point center(win.x_max() / 2, win.y_max() / 2);
int edge = 50;
int height = 0.5 * (1 + sqrt(2.0)) * edge; //r = 1/2 * ( 1 + sqrt(2)) * s
rt_tiling myRtTiling(Point(10, 100), edge, height, 20, 5);
win.attach(myRtTiling);
win.wait_for_button();
}
catch (exception& e) {
cout << e.what() << endl;
return 1;
}
catch (…) {
cout << "Exiting" << endl;
return 2;
}
[/code]
