# include <iostream.h> # include <graphics.h> # include <conio.h> # include <math.h> class RectangularCoordinates { public: float x_min; float y_min; float x_max; float y_max; RectangularCoordinates(const float x1,const float y1, const float x2,const float y2) { x_min=x1; y_min=y1; x_max=x2; y_max=y2; } }; void show_screen( ); void apply_window_to_viewport_coordinate_transformation( const RectangularCoordinates, const RectangularCoordinates, int &,int &); void Rectangle(const int,const int,const int,const int); void Line(const int,const int,const int,const int); int main( ) { int driver=VGA; int mode=VGAHI; initgraph(&driver,&mode,\"..\\\\Bgi\"); show_screen( ); setcolor(15); Line(90,150,90,390); Line(50,350,320,350); Line(400,150,400,390); Line(360,350,580,350); RectangularCoordinates WC(130,180,290,300); RectangularCoordinates VC(440,230,550,300); setcolor(15); Line(90,180,95,180); Line(90,300,95,300); Line(130,345,130,350); Line(290,345,290,350); Line(400,230,405,230); Line(400,300,405,300); Line(440,345,440,350); Line(550,345,550,350); setcolor(15); Rectangle(WC.x_min,WC.y_min,WC.x_max,WC.y_max); Rectangle(VC.x_min,VC.y_min,VC.x_max,VC.y_max); setcolor(15); settextstyle(0,0,1); outtextxy(50,175,\"YW\"); outtextxy(50,295,\"YW\"); outtextxy(110,360,\"XW\"); outtextxy(280,360,\"XW\"); outtextxy(360,225,\"YV\"); outtextxy(360,295,\"YV\"); outtextxy(420,360,\"XV\"); outtextxy(530,360,\"XV\"); outtextxy(182,170,\"Window\"); outtextxy(140,390,\"World Coordinates\"); outtextxy(462,220,\"Viewport\"); outtextxy(420,390,\"Device Coordinates\"); settextstyle(2,0,4); outtextxy(67,175,\"min\"); outtextxy(67,295,\"max\"); outtextxy(127,360,\"min\"); outtextxy(297,360,\"max\"); outtextxy(377,225,\"min\"); outtextxy(377,295,\"max\"); outtextxy(437,360,\"min\"); outtextxy(547,360,\"max\"); int x=210; int y=240; putpixel(x,y,15); setcolor(15); settextstyle(2,0,4); outtextxy((x-20),(y+3),\"(XW,YW)\"); char Key=NULL; do { Key=getch( ); } while(Key!=\'T\' && Key!=\'t\'); settextstyle(0,0,1); setcolor(0); outtextxy(36,450,\" Press \'T\' to see the Window-to-Viewport Coordinate Transformation. \"); setcolor(15); outtextxy(38,450,\"----------------------- ---------------------\"); setcolor(12); outtextxy(222,450,\" Press any Key to exit. \"); apply_window_to_viewport_coordinate_transformation(WC,VC,x,y); putpixel(x,y,14); setcolor(15); settextstyle(2,0,4); outtextxy((x-20),(y+3),\"(XV,YV)\"); getch( ); return 0; } //----- apply_window_to_viewport_coordinate_transformation( ) ---------// void apply_window_to_viewport_coordinate_transformation( const RectangularCoordinates wc, const RectangularCoordinates vc, int &x,int &y) { float Sx=((vc.x_max-vc.x_min)/(wc.x_max-wc.x_min)); float Sy=((vc.y_max-vc.y_min)/(wc.y_max-wc.y_min)); float Tx=vc.x_min; float Ty=vc.y_min; x=(Tx+(Sx*(x-wc.x_min))); y=(Ty+(Sy*(y-wc.y_min))); } //--------------------------- Rectangle( ) ----------------------------// void Rectangle(const int x_1,const int y_1,const int x_2,const int y_2) { Line(x_1,y_1,x_2,y_1); Line(x_2,y_1,x_2,y_2); Line(x_2,y_2,x_1,y_2); Line(x_1,y_2,x_1,y_1); } //-------------------------- Line( ) ------------------------// void Line(const int x_1,const int y_1,const int x_2,const int y_2) { int color=getcolor( ); int x1=x_1; int y1=y_1; int x2=x_2; int y2=y_2; if(x_1>x_2) { x1=x_2; y1=y_2; x2=x_1; y2=y_1; } int dx=abs(x2-x1); int dy=abs(y2-y1); int inc_dec=((y2>=y1)?1:-1); if(dx>dy) { int two_dy=(2*dy); int two_dy_dx=(2*(dy-dx)); int p=((2*dy)-dx); int x=x1; int y=y1; putpixel(x,y,color); while(x<x2) { x++; if(p<0) p+=two_dy; else { y+=inc_dec; p+=two_dy_dx; } putpixel(x,y,color); } } else { int two_dx=(2*dx); int two_dx_dy=(2*(dx-dy)); int p=((2*dx)-dy); int x=x1; int y=y1; putpixel(x,y,color); while(y!=y2) { y+=inc_dec; if(p<0) p+=two_dx; else { x++; p+=two_dx_dy; } putpixel(x,y,color); } } } //-------------------------- show_screen( ) ---------------------------// void show_screen( ) { setfillstyle(1,1); bar(130,26,500,38); settextstyle(0,0,1); setcolor(15); outtextxy(5,5,\"******************************************************************************\"); outtextxy(5,17,\"*-**************************************************************************-*\"); outtextxy(5,29,\"*-------------- --------------*\"); outtextxy(5,41,\"*-**************************************************************************-*\"); outtextxy(5,53,\"*-**************************************************************************-*\"); setcolor(11); outtextxy(140,29,\"Window-to-Viewport Coordinate Transformation\"); setcolor(15); for(int count=0;count<=30;count++) outtextxy(5,(65+(count*12)),\"*-* *-*\"); outtextxy(5,438,\"*-**************************************************************************-*\"); outtextxy(5,450,\"*--- ----*\"); outtextxy(5,462,\"******************************************************************************\"); setcolor(12); outtextxy(36,450,\" Press \'T\' to see the Window-to-Viewport Coordinate Transformation. \"); }