矩阵的变换。包括缩放、平移、错切-the transformation matrix. Incl...原文链接
#include<graphics.h>
#include<math.h>
typedef struct Matrix
{
float _a11,_a12,_a13;
float _a21,_a22,_a23;
float _a31,_a32,_a33;
} Matrix;
typedef struct Vert3
{
float x;
float y;
float z;
} Vert3;
Matrix *MatTranslation(Matrix * mat,float xoffset,float yoffset)
{
mat->_a11=1.0f;mat->_a12=0.0f;mat->_a13=0.0f;
mat->_a21=0.0f;mat->_a22=1.0f;mat->_a23=0.0f;
mat->_a31=xoffset;mat->_a32=yoffset;mat->_a33=1.0f;
return mat;
}
Matrix *MatTranslationBS(Matrix * mat,float xoffset,float yoffset)
{
mat->_a11=xoffset;mat->_a12=0.0f;mat->_a13=0.0f;
mat->_a21=0.0f;mat->_a22=yoffset;mat->_a23=0.0f;
mat->_a31=0.0f;mat->_a32=0.0f;mat->_a33=1.0f;
return mat;
}
Matrix *MatTranslationCQ(Matrix * mat,float xoffset,float yoffset)
{
mat->_a11=1.0f;mat->_a12=xoffset;mat->_a13=0.0f;
mat->_a21=yoffset;mat->_a22=1.0f;mat->_a23=0.0f;
mat->_a31=0.0f;mat->_a32=0.0f;mat->_a33=1.0f;
return mat;
}
Matrix *MatTranslationx(Matrix * mat)
{
mat->_a11=1.0f;mat->_a12=0.0f;mat->_a13=0.0f;
mat->_a21=0.0f;mat->_a22=-1.0f;mat->_a23=0.0f;
mat->_a31=0.0f;mat->_a32=0.0f;mat->_a33=1.0f;
return mat;
}
Matrix *MatTranslationy(Matrix * mat)
{
mat->_a11=-1.0f;mat->_a12=0.0f;mat->_a13=0.0f;
mat->_a21=0.0f;mat->_a22=1.0f;mat->_a23=0.0f;
mat->_a31=0.0f;mat->_a32=0.0f;mat->_a33=1.0f;
return mat;
}
Matrix *MatTranslationyx(Matrix * mat)
{
mat->_a11=0.0f;mat->_a12=1.0f;mat->_a13=0.0f;
mat->_a21=1.0f;mat->_a22=0.0f;mat->_a23=0.0f;
mat->_a31=0.0f;mat->_a32=0.0f;mat->_a33=1.0f;
return mat;
}
Matrix *MatRotation(Matrix * mat,float alpha)
{
float sinalpha = (float)sin(alpha);
float cosalpha = (float)cos(alpha);
mat->_a11=cosalpha; mat->_a12=sinalpha; mat->_a13=0.0f;
mat->_a21=-sinalpha; mat->_a22=cosalpha; mat->_a23=0.0f;
mat->_a31=0.0f; mat->_a32=0.0f; mat->_a33=1.0f;
return mat;
}
Vert3 * MultVertWithMatrix(Vert3 *vertout, Vert3 *vertin, Matrix mat)
{
vertout->x = mat._a11 * vertin->x + mat ._a21 * vertin ->y + mat ._a31 * vertin ->z ;
vertout->y = mat._a12 * vertin->x + mat ._a22 * vertin ->y + mat ._a32 * vertin ->z ;
vertout->z = mat._a13 * vertin->x + mat ._a23 * vertin ->y + mat._a33 * vertin ->z ;
return vertout;
}
main()
{
Vert3 a[4]={{0,0,0},{0,0,0},{0,0,0}};
Vert3 c[4]={{0,0,0},{0,0,0},{0,0,0}};
Vert3 d[4]={{0,0,0},{0,0,0},{0,0,0}};
Vert3 e[4]={{0,0,0},{0,0,0},{0,0,0}};
Vert3 f[4]={{0,0,0},{0,0,0},{0,0,0}};
Vert3 b[4]={{150,150,1},{150,250,1},{200,250,1},{200,150,1}};
Matrix m={1,0,0,0,1,0,0,0,1};
int i,j;
int graphDriver=DETECT;
int graphMode=0;
initgraph(&graphDriver,&graphMode,"");
setbkcolor(0);
setcolor(1);
moveto(b[0].x,b[0].y);
for(j=0;j<4;j++)
lineto(b[j].x,b[j].y);
lineto(b[0].x,b[0].y);
setcolor(2);
MatTranslationBS(&m,1.30,1.6);
i=0;
MultVertWithMatrix(&a[i], &b[i], m);
moveto(a[0].x,a[0].y);
for(i=1;i<4;i++){
MultVertWithMatrix(&a[i],&b[i], m);
lineto(a[i].x,a[i].y);
}
lineto(a[0].x,a[0].y);
setcolor(3);
MatTranslation(&m,100,200);
i=0;
MultVertWithMatrix(&c[i], &b[i], m);
moveto(c[0].x,c[0].y);
for(i=1;i<4;i++){
MultVertWithMatrix(&c[i],&b[i], m);
lineto(c[i].x,c[i].y);
}
lineto(c[0].x,c[0].y);
setcolor(4);
MatRotation(&m,-0.6);
i=0;
MultVertWithMatrix(&d[i], &b[i], m);
moveto(d[0].x,d[0].y);
for(i=1;i<4;i++){
MultVertWithMatrix(&d[i],&b[i], m);
lineto(d[i].x,d[i].y);
}
lineto(d[0].x,d[0].y);
setcolor(5);
MatTranslationyx(&m);
i=0;
MultVertWithMatrix(&e[i], &b[i], m);
moveto(e[0].x,e[0].y);
for(i=1;i<4;i++){
MultVertWithMatrix(&e[i],&b[i], m);
lineto(e[i].x,e[i].y);
}
lineto(e[0].x,e[0].y);
setcolor(6);
MatTranslationCQ(&m,0.6,0.9);
i=0;
MultVertWithMatrix(&f[i], &b[i], m);
moveto(f[0].x,f[0].y);
for(i=1;i<4;i++){
MultVertWithMatrix(&f[i],&b[i], m);
lineto(f[i].x,f[i].y);
}
lineto(f[0].x,f[0].y);
getch();
closegraph();
}
)
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