geometry.cpp

   1 #include "geometry.h"
   2 #include "math.h"
   3 #include <vector>
   4
   5 Linha::Linha(double x1,double y1,double x2, double y2) {
   6         vertices[0].x = x1;
   7         vertices[0].y = y1;
   8         vertices[1].x = x2;
   9         vertices[1].y = y2;
  10 }
  11
  12 Rect::Rect(double x1,double y1,double x2, double y2) {
  13         vertices[0].x = x1;
  14         vertices[0].y = y1;
  15         vertices[1].x = x2;
  16         vertices[1].y = y2;
  17         normaliza();
  18 }
  19
  20 void Rect::normaliza() {
  21         double xmin,xmax,ymin,ymax;
  22         xmin = std::min(vertices[0].x,vertices[1].x);
  23         xmax = std::max(vertices[0].x,vertices[1].x);
  24         ymin = std::min(vertices[0].y,vertices[1].y);
  25         ymax = std::max(vertices[0].y,vertices[1].y);
  26         vertices[0].x = xmin;
  27         vertices[1].x = xmax;
  28         vertices[0].y = ymin;
  29         vertices[1].y = ymax;
  30 }
  31
  32 void Linha::desenha() {
  33         glColor3f(0,0,0);
  34         glBegin(GL_LINES);
  35                 glVertex3f(vertices[0].x, vertices[0].y, 0.0f); // origin of the line
  36                 glVertex3f(vertices[1].x, vertices[1].y, 0.0f); // origin of the line
  37         glEnd( );
  38 }
  39
  40 void Polygon::desenha() {
  41         int n = linhas.size();
  42         for (int i = 0; i < n; i++) {
  43                 linhas[i].desenha();
  44         }
  45 }
  46
  47 double operator*(const Ponto &a, const Ponto &b) {
  48         return a.x * b.y - b.x * a.y;
  49 }
  50
  51 Ponto operator-(const Ponto &a, const Ponto &b) {
  52         Ponto ret;
  53         ret.x = a.x - b.x;
  54         ret.y = a.y - b.y;
  55         return ret;
  56 }
  57
  58 Ponto operator+(const Ponto &a, const Ponto &b) {
  59         Ponto ret;
  60         ret.x = a.x + b.x;
  61         ret.y = a.y + b.y;
  62         return ret;
  63 }
  64
  65 double distance(const Ponto &a,const Ponto &b) {
  66         return sqrt((a.x-b.x)*(a.x-b.x)+(a.y-b.y)*(a.y-b.y));
  67 }
  68
  69 void drawCircle(double radius, int lines)
  70 {
  71         double i2rad = PI/(lines/2.0);
  72         glBegin(GL_LINE_LOOP);
  73         for (int i=0; i < lines; i++) {
  74                 double degInRad = i*i2rad;
  75                 glVertex2f(cos(degInRad)*radius,sin(degInRad)*radius);
  76         }
  77
  78         glEnd();
  79 }