任意角度图片旋转

韩冰

void S_PicXZ(Graphics::TBitmap *Source,Graphics::TBitmap *NewPic,int angle)// { ; j0 \4 @! o! k: N+ m: Tif(angle>180)angle=360-angle; if(angle<-180)angle=360+angle;

8 _; J9 p; D- g0 u" G

float radians=(2*3.1416*angle)/360; + @6 v0 Q4 t1 r, ~& [3 O/ \float cosine=(float)cos(radians); float sine=(float)sin(radians); ) @ m; ?( I, H \4 V& Cfloat Point1x=(-Source->Height*sine); float Point1y=(Source->Height*cosine); float Point2x=(Source->Width*cosine-Source->Height*sine); 1 p. t2 w; e9 j6 A* dfloat Point2y=(Source->Height*cosine+Source->Width*sine); 4 B0 s+ h+ A. m( Dfloat Point3x=(Source->Width*cosine); + w0 q9 |; G, kfloat Point3y=(Source->Width*sine); float minx=min((float)0,min(Point1x,min(Point2x,Point3x))); ( V2 [' u, \5 p qfloat miny=min((float)0,min(Point1y,min(Point2y,Point3y))); float maxx=max(Point1x,max(Point2x,Point3x)); float maxy=max(Point1y,max(Point2y,Point3y)); # P( @/ {& m) |, D6 Uint DestBitmapWidth,DestBitmapHeight; if(angle>90&&angle<180) DestBitmapWidth=(int)ceil(-minx); else 9 r+ B$ M p# D* [' M+ i" {DestBitmapWidth=(int)ceil(maxx-minx);

( t: d2 C2 C0 f* E& f

if(angle>-180&&angle<-90) $ t) @. F( {. z) D; S+ b9 jDestBitmapHeight=(int)ceil(-miny); 0 s. g2 f8 u J9 `else ' I/ a/ R3 ~) ~+ GDestBitmapHeight=(int)ceil(maxy-miny);

NewPic->Height=DestBitmapHeight; 3 L6 H; k# q* ?1 t" ^NewPic->Width=DestBitmapWidth; % z( A. n3 f4 L7 [8 lfor(int x=0;x<DestBitmapWidth;x++) { $ [/ f5 T+ m4 M( M* R& ofor(int y=0;y<DestBitmapHeight;y++){ % a" e* [# |4 P. X" l9 Cint SrcBitmapx=(int)((x+minx)*cosine+(y+miny)*sine); 6 ^/ Z5 n4 q4 A- M- `int SrcBitmapy=(int)((y+miny)*cosine-(x+minx)*sine); if(SrcBitmapx>=0&&SrcBitmapx<Source->Width&&SrcBitmapy>=0&& , d) ?. Y9 O8 Q" p$ }$ A' y$ G1 ]SrcBitmapy<Source->Height) % P4 }1 p& P6 d# L1 h6 l5 C* @{ 1 ^0 s% L% N: P' `/ D$ G# ^6 FNewPic->Canvas->ixels[x][y]= Source->Canvas->ixels[SrcBitmapx][SrcBitmapy]; . K& J5 Y1 o2 l# y9 x" }2 u4 O} ( b, A9 @1 x( P/ E1 f} ) J& q) \& J( Z0 T* V+ f2 ~4 H} * R$ k1 I0 S- T9 M; R1 Q" W}