coders/gradient.c - platform/external/ImageMagick - Git at Google

 /*
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %                                                                             %
 %                                                                             %
 %                                                                             %
 %            GGGG  RRRR    AAA   DDDD   IIIII  EEEEE  N   N  TTTTT            %
 %           G      R   R  A   A  D   D    I    E      NN  N    T              %
 %           G  GG  RRRR   AAAAA  D   D    I    EEE    N N N    T              %
 %           G   G  R R    A   A  D   D    I    E      N  NN    T              %
 %            GGG   R  R   A   A  DDDD   IIIII  EEEEE  N   N    T              %
 %                                                                             %
 %                                                                             %
 %                   Read An Image Filled Using Gradient.                      %
 %                                                                             %
 %                              Software Design                                %
 %                                   Cristy                                    %
 %                                 July 1992                                   %
 %                                                                             %
 %                                                                             %
 %  Copyright 1999-2020 ImageMagick Studio LLC, a non-profit organization      %
 %  dedicated to making software imaging solutions freely available.           %
 %                                                                             %
 %  You may not use this file except in compliance with the License.  You may  %
 %  obtain a copy of the License at                                            %
 %                                                                             %
 %    https://imagemagick.org/script/license.php                               %
 %                                                                             %
 %  Unless required by applicable law or agreed to in writing, software        %
 %  distributed under the License is distributed on an "AS IS" BASIS,          %
 %  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.   %
 %  See the License for the specific language governing permissions and        %
 %  limitations under the License.                                             %
 %                                                                             %
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %
 %
 */

 /*
   Include declarations.
 */
 #include "MagickCore/studio.h"
 #include "MagickCore/attribute.h"
 #include "MagickCore/blob.h"
 #include "MagickCore/blob-private.h"
 #include "MagickCore/channel.h"
 #include "MagickCore/color.h"
 #include "MagickCore/color-private.h"
 #include "MagickCore/colorspace-private.h"
 #include "MagickCore/constitute.h"
 #include "MagickCore/draw.h"
 #include "MagickCore/exception.h"
 #include "MagickCore/exception-private.h"
 #include "MagickCore/image.h"
 #include "MagickCore/image-private.h"
 #include "MagickCore/list.h"
 #include "MagickCore/magick.h"
 #include "MagickCore/memory_.h"
 #include "MagickCore/paint.h"
 #include "MagickCore/pixel-accessor.h"
 #include "MagickCore/quantum-private.h"
 #include "MagickCore/static.h"
 #include "MagickCore/string_.h"
 #include "MagickCore/module.h"
 #include "MagickCore/studio.h"

 /*
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %                                                                             %
 %                                                                             %
 %                                                                             %
 %   R e a d G R A D I E N T I m a g e                                         %
 %                                                                             %
 %                                                                             %
 %                                                                             %
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %
 %  ReadGRADIENTImage creates a gradient image and initializes it to
 %  the color range as specified by the filename.  It allocates the memory
 %  necessary for the new Image structure and returns a pointer to the new
 %  image.
 %
 %  The format of the ReadGRADIENTImage method is:
 %
 %      Image *ReadGRADIENTImage(const ImageInfo *image_info,
 %        ExceptionInfo *exception)
 %
 %  A description of each parameter follows:
 %
 %    o image_info: the image info.
 %
 %    o exception: return any errors or warnings in this structure.
 %
 */

 static Image *ReadXCImage(const ImageInfo *image_info,ExceptionInfo *exception)
 {
   Image
     *image;

   MagickBooleanType
     status;

   PixelInfo
     pixel;

   register ssize_t
     x;

   register Quantum
     *q;

   ssize_t
     y;

   /*
     Initialize Image structure.
   */
   assert(image_info != (const ImageInfo *) NULL);
   assert(image_info->signature == MagickCoreSignature);
   if (image_info->debug != MagickFalse)
     (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",
       image_info->filename);
   assert(exception != (ExceptionInfo *) NULL);
   assert(exception->signature == MagickCoreSignature);
   image=AcquireImage(image_info,exception);
   if (image->columns == 0)
     image->columns=1;
   if (image->rows == 0)
     image->rows=1;
   status=SetImageExtent(image,image->columns,image->rows,exception);
   if (status == MagickFalse)
     return(DestroyImageList(image));
   (void) CopyMagickString(image->filename,image_info->filename,
     MagickPathExtent);
   if (*image_info->filename == '\0')
     pixel=image->background_color;
   else
     {
       status=QueryColorCompliance((char *) image_info->filename,AllCompliance,
         &pixel,exception);
       if (status == MagickFalse)
         {
           image=DestroyImage(image);
           return((Image *) NULL);
         }
     }
   (void) SetImageColorspace(image,pixel.colorspace,exception);
   image->alpha_trait=pixel.alpha_trait;
   for (y=0; y < (ssize_t) image->rows; y++)
   {
     q=QueueAuthenticPixels(image,0,y,image->columns,1,exception);
     if (q == (Quantum *) NULL)
       break;
     for (x=0; x < (ssize_t) image->columns; x++)
     {
       SetPixelViaPixelInfo(image,&pixel,q);
       q+=GetPixelChannels(image);
     }
     if (SyncAuthenticPixels(image,exception) == MagickFalse)
       break;
   }
   return(GetFirstImageInList(image));
 }

 static Image *ReadGRADIENTImage(const ImageInfo *image_info,
   ExceptionInfo *exception)
 {
   char
     start_color[MagickPathExtent],
     stop_color[MagickPathExtent];

   Image
     *image;

   ImageInfo
     *read_info;

   MagickBooleanType
     status;

   StopInfo
     *stops;

   /*
     Identify start and stop gradient colors.
   */
   assert(image_info != (const ImageInfo *) NULL);
   assert(image_info->signature == MagickCoreSignature);
   if (image_info->debug != MagickFalse)
     (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",
       image_info->filename);
   assert(exception != (ExceptionInfo *) NULL);
   assert(exception->signature == MagickCoreSignature);
   (void) CopyMagickString(start_color,"white",MagickPathExtent);
   (void) CopyMagickString(stop_color,"black",MagickPathExtent);
   if (*image_info->filename != '\0')
     {
       register char
         *p;

       (void) CopyMagickString(start_color,image_info->filename,
         MagickPathExtent);
       for (p=start_color; (*p != '-') && (*p != '\0'); p++)
         if (*p == '(')
           {
             for (p++; (*p != ')') && (*p != '\0'); p++);
             if (*p == '\0')
               break;
           }
       if (*p == '-')
         (void) CopyMagickString(stop_color,p+1,MagickPathExtent);
       *p='\0';
     }
   /*
     Create base gradient image from start color.
   */
   read_info=CloneImageInfo(image_info);
   SetImageInfoBlob(read_info,(void *) NULL,0);
   (void) CopyMagickString(read_info->filename,start_color,MagickPathExtent);
   image=ReadXCImage(read_info,exception);
   read_info=DestroyImageInfo(read_info);
   if (image == (Image *) NULL)
     return((Image *) NULL);
   /*
     Create gradient stops.
   */
   stops=(StopInfo *) AcquireQuantumMemory(2,sizeof(*stops));
   if (stops == (StopInfo *) NULL)
     ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
   stops[0].offset=0.0;
   stops[1].offset=1.0;
   status=QueryColorCompliance(start_color,AllCompliance,&stops[0].color,
     exception);
   if (status != MagickFalse)
     status=QueryColorCompliance(stop_color,AllCompliance,&stops[1].color,
       exception);
   if (status == MagickFalse)
     {
       stops=(StopInfo *) RelinquishMagickMemory(stops);
       image=DestroyImage(image);
       return((Image *) NULL);
     }
   (void) SetImageColorspace(image,stops[0].color.colorspace,exception);
   if ((stops[0].color.alpha_trait != UndefinedPixelTrait) ||
       (stops[1].color.alpha_trait != UndefinedPixelTrait))
     SetImageAlpha(image,TransparentAlpha,exception);
   /*
     Paint gradient.
   */
   status=GradientImage(image,LocaleCompare(image_info->magick,"GRADIENT") == 0 ?
     LinearGradient : RadialGradient,PadSpread,stops,2,exception);
   stops=(StopInfo *) RelinquishMagickMemory(stops);
   if (status == MagickFalse)
     {
       image=DestroyImageList(image);
       return((Image *) NULL);
     }
   return(GetFirstImageInList(image));
 }

 /*
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %                                                                             %
 %                                                                             %
 %                                                                             %
 %   R e g i s t e r G R A D I E N T I m a g e                                 %
 %                                                                             %
 %                                                                             %
 %                                                                             %
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %
 %  RegisterGRADIENTImage() adds attributes for the GRADIENT image format
 %  to the list of supported formats.  The attributes include the image format
 %  tag, a method to read and/or write the format, whether the format
 %  supports the saving of more than one frame to the same file or blob,
 %  whether the format supports native in-memory I/O, and a brief
 %  description of the format.
 %
 %  The format of the RegisterGRADIENTImage method is:
 %
 %      size_t RegisterGRADIENTImage(void)
 %
 */
 ModuleExport size_t RegisterGRADIENTImage(void)
 {
   MagickInfo
     *entry;

   entry=AcquireMagickInfo("GRADIENT","GRADIENT",
     "Gradual linear passing from one shade to another");
   entry->decoder=(DecodeImageHandler *) ReadGRADIENTImage;
   entry->flags^=CoderAdjoinFlag;
   entry->flags|=CoderRawSupportFlag;
   entry->format_type=ImplicitFormatType;
   (void) RegisterMagickInfo(entry);
   entry=AcquireMagickInfo("GRADIENT","RADIAL-GRADIENT",
     "Gradual radial passing from one shade to another");
   entry->decoder=(DecodeImageHandler *) ReadGRADIENTImage;
   entry->flags^=CoderAdjoinFlag;
   entry->flags|=CoderRawSupportFlag;
   entry->format_type=ImplicitFormatType;
   (void) RegisterMagickInfo(entry);
   return(MagickImageCoderSignature);
 }

 /*
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %                                                                             %
 %                                                                             %
 %                                                                             %
 %   U n r e g i s t e r G R A D I E N T I m a g e                             %
 %                                                                             %
 %                                                                             %
 %                                                                             %
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %
 %  UnregisterGRADIENTImage() removes format registrations made by the
 %  GRADIENT module from the list of supported formats.
 %
 %  The format of the UnregisterGRADIENTImage method is:
 %
 %      UnregisterGRADIENTImage(void)
 %
 */
 ModuleExport void UnregisterGRADIENTImage(void)
 {
   (void) UnregisterMagickInfo("RADIAL-GRADIENT");
   (void) UnregisterMagickInfo("GRADIENT");
 }
	/*
	%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
	% %
	% %
	% %
	% GGGG RRRR AAA DDDD IIIII EEEEE N N TTTTT %
	% G R R A A D D I E NN N T %
	% G GG RRRR AAAAA D D I EEE N N N T %
	% G G R R A A D D I E N NN T %
	% GGG R R A A DDDD IIIII EEEEE N N T %
	% %
	% %
	% Read An Image Filled Using Gradient. %
	% %
	% Software Design %
	% Cristy %
	% July 1992 %
	% %
	% %
	% Copyright 1999-2020 ImageMagick Studio LLC, a non-profit organization %
	% dedicated to making software imaging solutions freely available. %
	% %
	% You may not use this file except in compliance with the License. You may %
	% obtain a copy of the License at %
	% %
	% https://imagemagick.org/script/license.php %
	% %
	% Unless required by applicable law or agreed to in writing, software %
	% distributed under the License is distributed on an "AS IS" BASIS, %
	% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. %
	% See the License for the specific language governing permissions and %
	% limitations under the License. %
	% %
	%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
	%
	%
	*/

	/*
	Include declarations.
	*/
	#include "MagickCore/studio.h"
	#include "MagickCore/attribute.h"
	#include "MagickCore/blob.h"
	#include "MagickCore/blob-private.h"
	#include "MagickCore/channel.h"
	#include "MagickCore/color.h"
	#include "MagickCore/color-private.h"
	#include "MagickCore/colorspace-private.h"
	#include "MagickCore/constitute.h"
	#include "MagickCore/draw.h"
	#include "MagickCore/exception.h"
	#include "MagickCore/exception-private.h"
	#include "MagickCore/image.h"
	#include "MagickCore/image-private.h"
	#include "MagickCore/list.h"
	#include "MagickCore/magick.h"
	#include "MagickCore/memory_.h"
	#include "MagickCore/paint.h"
	#include "MagickCore/pixel-accessor.h"
	#include "MagickCore/quantum-private.h"
	#include "MagickCore/static.h"
	#include "MagickCore/string_.h"
	#include "MagickCore/module.h"
	#include "MagickCore/studio.h"

	/*
	%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
	% %
	% %
	% %
	% R e a d G R A D I E N T I m a g e %
	% %
	% %
	% %
	%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
	%
	% ReadGRADIENTImage creates a gradient image and initializes it to
	% the color range as specified by the filename. It allocates the memory
	% necessary for the new Image structure and returns a pointer to the new
	% image.
	%
	% The format of the ReadGRADIENTImage method is:
	%
	% Image ReadGRADIENTImage(const ImageInfo image_info,
	% ExceptionInfo *exception)
	%
	% A description of each parameter follows:
	%
	% o image_info: the image info.
	%
	% o exception: return any errors or warnings in this structure.
	%
	*/

	static Image ReadXCImage(const ImageInfo image_info,ExceptionInfo *exception)
	{
	Image
	*image;

	MagickBooleanType
	status;

	PixelInfo
	pixel;

	register ssize_t
	x;

	register Quantum
	*q;

	ssize_t
	y;

	/*
	Initialize Image structure.
	*/
	assert(image_info != (const ImageInfo *) NULL);
	assert(image_info->signature == MagickCoreSignature);
	if (image_info->debug != MagickFalse)
	(void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",
	image_info->filename);
	assert(exception != (ExceptionInfo *) NULL);
	assert(exception->signature == MagickCoreSignature);
	image=AcquireImage(image_info,exception);
	if (image->columns == 0)
	image->columns=1;
	if (image->rows == 0)
	image->rows=1;
	status=SetImageExtent(image,image->columns,image->rows,exception);
	if (status == MagickFalse)
	return(DestroyImageList(image));
	(void) CopyMagickString(image->filename,image_info->filename,
	MagickPathExtent);
	if (*image_info->filename == '\0')
	pixel=image->background_color;
	else
	{
	status=QueryColorCompliance((char *) image_info->filename,AllCompliance,
	&pixel,exception);
	if (status == MagickFalse)
	{
	image=DestroyImage(image);
	return((Image *) NULL);
	}
	}
	(void) SetImageColorspace(image,pixel.colorspace,exception);
	image->alpha_trait=pixel.alpha_trait;
	for (y=0; y < (ssize_t) image->rows; y++)
	{
	q=QueueAuthenticPixels(image,0,y,image->columns,1,exception);
	if (q == (Quantum *) NULL)
	break;
	for (x=0; x < (ssize_t) image->columns; x++)
	{
	SetPixelViaPixelInfo(image,&pixel,q);
	q+=GetPixelChannels(image);
	}
	if (SyncAuthenticPixels(image,exception) == MagickFalse)
	break;
	}
	return(GetFirstImageInList(image));
	}

	static Image ReadGRADIENTImage(const ImageInfo image_info,
	ExceptionInfo *exception)
	{
	char
	start_color[MagickPathExtent],
	stop_color[MagickPathExtent];

	Image
	*image;

	ImageInfo
	*read_info;

	MagickBooleanType
	status;

	StopInfo
	*stops;

	/*
	Identify start and stop gradient colors.
	*/
	assert(image_info != (const ImageInfo *) NULL);
	assert(image_info->signature == MagickCoreSignature);
	if (image_info->debug != MagickFalse)
	(void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",
	image_info->filename);
	assert(exception != (ExceptionInfo *) NULL);
	assert(exception->signature == MagickCoreSignature);
	(void) CopyMagickString(start_color,"white",MagickPathExtent);
	(void) CopyMagickString(stop_color,"black",MagickPathExtent);
	if (*image_info->filename != '\0')
	{
	register char
	*p;

	(void) CopyMagickString(start_color,image_info->filename,
	MagickPathExtent);
	for (p=start_color; (p != '-') && (p != '\0'); p++)
	if (*p == '(')
	{
	for (p++; (p != ')') && (p != '\0'); p++);
	if (*p == '\0')
	break;
	}
	if (*p == '-')
	(void) CopyMagickString(stop_color,p+1,MagickPathExtent);
	*p='\0';
	}
	/*
	Create base gradient image from start color.
	*/
	read_info=CloneImageInfo(image_info);
	SetImageInfoBlob(read_info,(void *) NULL,0);
	(void) CopyMagickString(read_info->filename,start_color,MagickPathExtent);
	image=ReadXCImage(read_info,exception);
	read_info=DestroyImageInfo(read_info);
	if (image == (Image *) NULL)
	return((Image *) NULL);
	/*
	Create gradient stops.
	*/
	stops=(StopInfo ) AcquireQuantumMemory(2,sizeof(stops));
	if (stops == (StopInfo *) NULL)
	ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
	stops[0].offset=0.0;
	stops[1].offset=1.0;
	status=QueryColorCompliance(start_color,AllCompliance,&stops[0].color,
	exception);
	if (status != MagickFalse)
	status=QueryColorCompliance(stop_color,AllCompliance,&stops[1].color,
	exception);
	if (status == MagickFalse)
	{
	stops=(StopInfo *) RelinquishMagickMemory(stops);
	image=DestroyImage(image);
	return((Image *) NULL);
	}
	(void) SetImageColorspace(image,stops[0].color.colorspace,exception);
	if ((stops[0].color.alpha_trait != UndefinedPixelTrait) \|\|
	(stops[1].color.alpha_trait != UndefinedPixelTrait))
	SetImageAlpha(image,TransparentAlpha,exception);
	/*
	Paint gradient.
	*/
	status=GradientImage(image,LocaleCompare(image_info->magick,"GRADIENT") == 0 ?
	LinearGradient : RadialGradient,PadSpread,stops,2,exception);
	stops=(StopInfo *) RelinquishMagickMemory(stops);
	if (status == MagickFalse)
	{
	image=DestroyImageList(image);
	return((Image *) NULL);
	}
	return(GetFirstImageInList(image));
	}

	/*
	%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
	% %
	% %
	% %
	% R e g i s t e r G R A D I E N T I m a g e %
	% %
	% %
	% %
	%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
	%
	% RegisterGRADIENTImage() adds attributes for the GRADIENT image format
	% to the list of supported formats. The attributes include the image format
	% tag, a method to read and/or write the format, whether the format
	% supports the saving of more than one frame to the same file or blob,
	% whether the format supports native in-memory I/O, and a brief
	% description of the format.
	%
	% The format of the RegisterGRADIENTImage method is:
	%
	% size_t RegisterGRADIENTImage(void)
	%
	*/
	ModuleExport size_t RegisterGRADIENTImage(void)
	{
	MagickInfo
	*entry;

	entry=AcquireMagickInfo("GRADIENT","GRADIENT",
	"Gradual linear passing from one shade to another");
	entry->decoder=(DecodeImageHandler *) ReadGRADIENTImage;
	entry->flags^=CoderAdjoinFlag;
	entry->flags\|=CoderRawSupportFlag;
	entry->format_type=ImplicitFormatType;
	(void) RegisterMagickInfo(entry);
	entry=AcquireMagickInfo("GRADIENT","RADIAL-GRADIENT",
	"Gradual radial passing from one shade to another");
	entry->decoder=(DecodeImageHandler *) ReadGRADIENTImage;
	entry->flags^=CoderAdjoinFlag;
	entry->flags\|=CoderRawSupportFlag;
	entry->format_type=ImplicitFormatType;
	(void) RegisterMagickInfo(entry);
	return(MagickImageCoderSignature);
	}

	/*
	%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
	% %
	% %
	% %
	% U n r e g i s t e r G R A D I E N T I m a g e %
	% %
	% %
	% %
	%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
	%
	% UnregisterGRADIENTImage() removes format registrations made by the
	% GRADIENT module from the list of supported formats.
	%
	% The format of the UnregisterGRADIENTImage method is:
	%
	% UnregisterGRADIENTImage(void)
	%
	*/
	ModuleExport void UnregisterGRADIENTImage(void)
	{
	(void) UnregisterMagickInfo("RADIAL-GRADIENT");
	(void) UnregisterMagickInfo("GRADIENT");
	}