任意角度图片旋转

韩冰

void S_PicXZ(Graphics::TBitmap *Source,Graphics::TBitmap *NewPic,int angle)// + l6 L; B4 ^" j0 [. _{ if(angle>180)angle=360-angle; % O/ Q& [" |3 `5 ~' J) M% J' iif(angle<-180)angle=360+angle;

float radians=(2*3.1416*angle)/360; float cosine=(float)cos(radians); ' U& V* F7 e2 }1 \5 C1 ]/ ifloat sine=(float)sin(radians); float Point1x=(-Source->Height*sine); 3 b1 J( _) o& }7 l% o4 s3 k9 ~float Point1y=(Source->Height*cosine); $ w8 E( G+ y- {0 D4 |% {; tfloat Point2x=(Source->Width*cosine-Source->Height*sine); ! B) A1 o6 d" \" k( Afloat Point2y=(Source->Height*cosine+Source->Width*sine); V/ T P! Y( g- u3 Q6 m6 Q, z1 o dfloat Point3x=(Source->Width*cosine); 1 X8 A0 T7 f/ p/ a- z2 v$ dfloat Point3y=(Source->Width*sine); ! C, n' h1 o) S. a2 V9 i9 I( Nfloat minx=min((float)0,min(Point1x,min(Point2x,Point3x))); float miny=min((float)0,min(Point1y,min(Point2y,Point3y))); + F4 l3 r4 y9 r, P5 D5 Ffloat maxx=max(Point1x,max(Point2x,Point3x)); ) F9 F& ]+ n# h5 _2 Ifloat maxy=max(Point1y,max(Point2y,Point3y)); 6 T, K' b: }! R. lint DestBitmapWidth,DestBitmapHeight; if(angle>90&&angle<180) DestBitmapWidth=(int)ceil(-minx); 5 g2 {$ `. W. A7 c& ]else DestBitmapWidth=(int)ceil(maxx-minx);

if(angle>-180&&angle<-90) DestBitmapHeight=(int)ceil(-miny); else ( U. Y6 n' P2 R6 aDestBitmapHeight=(int)ceil(maxy-miny);

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NewPic->Height=DestBitmapHeight; NewPic->Width=DestBitmapWidth; / N8 W3 ~; i- i0 R8 D8 f* r% ]1 z! `for(int x=0;x<DestBitmapWidth;x++) { 3 }$ A1 |7 q9 G2 d. Mfor(int y=0;y<DestBitmapHeight;y++){ 3 q7 X/ _. V4 _2 t1 h7 b3 cint SrcBitmapx=(int)((x+minx)*cosine+(y+miny)*sine); int SrcBitmapy=(int)((y+miny)*cosine-(x+minx)*sine); if(SrcBitmapx>=0&&SrcBitmapx<Source->Width&&SrcBitmapy>=0&& SrcBitmapy<Source->Height) ; R7 Q6 E+ f1 y( s2 B2 b) F* X{ - F" P# b( H& A! \NewPic->Canvas->ixels[x][y]= , v7 l/ a3 d9 L6 c4 FSource->Canvas->ixels[SrcBitmapx][SrcBitmapy]; 9 s z2 Y& {- T& Y8 p} ; h: H+ \' A/ M0 m$ r} 1 t8 U2 j) {% g0 |6 e} }