# include <iostream.h> # include <graphics.h> # include <conio.h> # include <math.h> # define Xc -0.3 # define Yc 0.3 # define Zc -1.0 void show_screen( ); void draw_3d_polygon(int [5][3],int [8][2],int [5][5]); void get_projected_point(int&,int&,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( ); int vertices[5][3]={ {245,325,75}, // base front left {395,325,75}, // base front right {395,325,-75}, // base back right {245,325,-75}, // base back left {320,125,0} // top }; int edges[8][2]={ // first is starting point vertex number // second is ending point vertex number {0,3} , {3,2} , {2,1} , {1,0} , {0,4} , {3,4} , {2,4} , {1,4} }; int surfaces[5][5]={ // First entry is number of edges // Rest entries are edge numbers {4,0,1,2,3}, {3,0,4,5} , {3,1,5,6} , {3,2,6,7} , {3,3,4,7} }; for(int i=0;i<5;i++) get_projected_point(vertices[i][0],vertices[i][1],vertices[i][2]); setcolor(15); draw_3d_polygon(vertices,edges,surfaces); settextstyle(2,0,4); setcolor(11); outtextxy(300,355,\"S1\"); outtextxy(260,270,\"S2\"); outtextxy(310,250,\"S3\"); outtextxy(370,280,\"S4\"); outtextxy(310,317,\"S5\"); setcolor(10); outtextxy(255,315,\"E1\"); outtextxy(320,291,\"E2\"); outtextxy(403,315,\"E3\"); outtextxy(310,337,\"E4\"); outtextxy(250,250,\"E5\"); outtextxy(288,240,\"E6\"); outtextxy(390,240,\"E7\"); outtextxy(356,260,\"E8\"); setcolor(14); outtextxy(212,344,\"V1\"); outtextxy(255,293,\"V2\"); outtextxy(420,293,\"V3\"); outtextxy(370,350,\"V4\"); outtextxy(320,115,\"V5\"); getch( ); closegraph( ); return 0; } /************************************************************************/ //------------------------- draw_3d_polygon( ) -----------------------// /************************************************************************/ void draw_3d_polygon(int vertices[5][3],int edges[8][2],int surfaces[5][5]) { for(int i=0;i<5;i++) { for(int j=1;j<=surfaces[i][0];j++) { int x_1=vertices[edges[surfaces[i][j]][0]][0]; int y_1=vertices[edges[surfaces[i][j]][0]][1]; int x_2=vertices[edges[surfaces[i][j]][1]][0]; int y_2=vertices[edges[surfaces[i][j]][1]][1]; Line(x_1,y_1,x_2,y_2); } } } /************************************************************************/ //--------------------- get_projected_point( ) -----------------------// /************************************************************************/ void get_projected_point(int& x,int& y,int& z) { float projection_matrix[4][4]={ { -Zc,0,0,0 }, { 0,-Zc,0,0 }, { Xc,Yc,0,1 }, { 0,0,0,-Zc } }; float matrix3d[4]={x,y,z,1}; float matrix2d[4]={0,0,0,0}; for(int count_1=0;count_1<4;count_1++) { for(int count_2=0;count_2<4;count_2++) matrix2d[count_1]+= (matrix3d[count_2]*projection_matrix[count_2][count_1]); } x=(int)(matrix2d[0]+0.5); y=(int)(matrix2d[1]+0.5); z=(int)(matrix2d[2]+0.5); } //-------------------------- 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(205,26,438,38); settextstyle(0,0,1); setcolor(15); outtextxy(5,5,\"******************************************************************************\"); outtextxy(5,17,\"*-**************************************************************************-*\"); outtextxy(5,29,\"*----------------------- ----------------------*\"); outtextxy(5,41,\"*-**************************************************************************-*\"); outtextxy(5,53,\"*-**************************************************************************-*\"); setcolor(11); outtextxy(214,29,\"Polygon-Mesh Representation\"); 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(227,450,\" Press any key to exit \"); }