2 Copyright 1999-2011 ImageMagick Studio LLC, a non-profit organization
3 dedicated to making software imaging solutions freely available.
5 You may not use this file except in compliance with the License.
6 obtain a copy of the License at
8 http://www.imagemagick.org/script/license.php
10 Unless required by applicable law or agreed to in writing, software
11 distributed under the License is distributed on an "AS IS" BASIS,
12 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 See the License for the specific language governing permissions and
14 limitations under the License.
16 MagickCore image composite private methods.
18 #ifndef _MAGICKCORE_COMPOSITE_PRIVATE_H
19 #define _MAGICKCORE_COMPOSITE_PRIVATE_H
21 #if defined(__cplusplus) || defined(c_plusplus)
26 ImageMagick Alpha Composite Inline Methods (special export)
29 #include "magick/color.h"
30 #include "magick/image.h"
31 #include "magick/image-private.h"
33 static inline MagickRealType RoundToUnity(const MagickRealType value)
35 return(value < 0.0 ? 0.0 : (value > 1.0) ? 1.0 : value);
38 static inline MagickRealType MagickOver_(const MagickRealType p,
39 const MagickRealType alpha,const MagickRealType q,const MagickRealType beta)
41 return((1.0-QuantumScale*alpha)*p+(1.0-QuantumScale*beta)*q*
45 static inline void MagickCompositeOver(const PixelPacket *p,
46 const MagickRealType alpha,const PixelPacket *q,const MagickRealType beta,
47 PixelPacket *composite)
53 Compose pixel p over pixel q with the given opacities.
55 if (alpha == TransparentOpacity)
61 gamma=1.0-QuantumScale*QuantumScale*alpha*beta;
62 #if !defined(MAGICKCORE_HDRI_SUPPORT)
63 composite->opacity=(Quantum) (QuantumRange*(1.0-gamma)+0.5);
64 gamma=1.0/(gamma <= MagickEpsilon ? 1.0 : gamma);
65 SetRedPixelComponent(composite,gamma*MagickOver_((MagickRealType)
66 GetRedPixelComponent(p),alpha,(MagickRealType)
67 GetRedPixelComponent(q),beta)+0.5);
68 SetGreenPixelComponent(composite,gamma*MagickOver_((MagickRealType)
69 GetGreenPixelComponent(p),alpha,(MagickRealType)
70 GetGreenPixelComponent(q),beta)+0.5);
71 SetBluePixelComponent(composite,gamma*MagickOver_((MagickRealType)
72 GetBluePixelComponent(p),alpha,(MagickRealType)
73 GetBluePixelComponent(q),beta)+0.5);
75 SetOpacityPixelComponent(composite,QuantumRange*(1.0-gamma));
76 gamma=1.0/(gamma <= MagickEpsilon ? 1.0 : gamma);
77 SetRedPixelComponent(composite,gamma*MagickOver_((MagickRealType)
78 GetRedPixelComponent(p),alpha,(MagickRealType)
79 GetRedPixelComponent(q),beta));
80 SetGreenPixelComponent(composite,gamma*MagickOver_((MagickRealType)
81 GetGreenPixelComponent(p),alpha,(MagickRealType)
82 GetGreenPixelComponent(q),beta));
83 SetBluePixelComponent(composite,gamma*MagickOver_((MagickRealType)
84 GetBluePixelComponent(p),alpha,(MagickRealType)
85 GetBluePixelComponent(q),beta));
89 static inline void MagickPixelCompositeOver(const MagickPixelPacket *p,
90 const MagickRealType alpha,const MagickPixelPacket *q,
91 const MagickRealType beta,MagickPixelPacket *composite)
97 Compose pixel p over pixel q with the given opacities.
99 if (alpha == OpaqueOpacity)
104 gamma=1.0-QuantumScale*QuantumScale*alpha*beta;
105 composite->opacity=(MagickRealType) QuantumRange*(1.0-gamma);
106 gamma=1.0/(fabs(gamma) <= MagickEpsilon ? 1.0 : gamma);
107 composite->red=gamma*MagickOver_(p->red,alpha,q->red,beta);
108 composite->green=gamma*MagickOver_(p->green,alpha,q->green,beta);
109 composite->blue=gamma*MagickOver_(p->blue,alpha,q->blue,beta);
110 if (q->colorspace == CMYKColorspace)
111 composite->index=gamma*MagickOver_(p->index,alpha,q->index,beta);
114 static inline void MagickPixelCompositePlus(const MagickPixelPacket *p,
115 const MagickRealType alpha,const MagickPixelPacket *q,
116 const MagickRealType beta,MagickPixelPacket *composite)
124 Add two pixels with the given opacities.
126 Sa=1.0-QuantumScale*alpha;
127 Da=1.0-QuantumScale*beta;
128 gamma=RoundToUnity(Sa+Da); /* 'Plus' blending -- not 'Over' blending */
129 composite->opacity=(MagickRealType) QuantumRange*(1.0-gamma);
130 gamma=1.0/(fabs(gamma) <= MagickEpsilon ? 1.0 : gamma);
131 composite->red=gamma*(Sa*p->red+Da*q->red);
132 composite->green=gamma*(Sa*p->green+Da*q->green);
133 composite->blue=gamma*(Sa*p->blue+Da*q->blue);
134 if (q->colorspace == CMYKColorspace)
135 composite->index=gamma*(Sa*p->index+Da*q->index);
139 Blend pixel colors p and q by the amount given.
141 static inline void MagickPixelCompositeBlend(const MagickPixelPacket *p,
142 const MagickRealType alpha,const MagickPixelPacket *q,
143 const MagickRealType beta,MagickPixelPacket *composite)
145 MagickPixelCompositePlus(p,(MagickRealType) (QuantumRange-alpha*
146 (QuantumRange-p->opacity)),q,(MagickRealType) (QuantumRange-beta*
147 (QuantumRange-q->opacity)),composite);
151 Blend pixel colors p and q by the amount given and area.
153 static inline void MagickPixelCompositeAreaBlend(const MagickPixelPacket *p,
154 const MagickRealType alpha,const MagickPixelPacket *q,
155 const MagickRealType beta,const MagickRealType area,
156 MagickPixelPacket *composite)
158 MagickPixelCompositePlus(p,(MagickRealType) QuantumRange-(1.0-area)*
159 (QuantumRange-alpha),q,(MagickRealType) (QuantumRange-area*(QuantumRange-
163 #if defined(__cplusplus) || defined(c_plusplus)