gfx/public/nsIImage.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
   7  * the License. You may obtain a copy of the License at
   8  * http://www.mozilla.org/MPL/
   9  *
  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  12  * for the specific language governing rights and limitations under the
  13  * License.
  14  *
  15  * The Original Code is mozilla.org code.
  16  *
  17  * The Initial Developer of the Original Code is
  18  * Netscape Communications Corporation.
  19  * Portions created by the Initial Developer are Copyright (C) 1998
  20  * the Initial Developer. All Rights Reserved.
  21  *
  22  * Contributor(s):
  23  *
  24  * Alternatively, the contents of this file may be used under the terms of
  25  * either of the GNU General Public License Version 2 or later (the "GPL"),
  26  * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  27  * in which case the provisions of the GPL or the LGPL are applicable instead
  28  * of those above. If you wish to allow use of your version of this file only
  29  * under the terms of either the GPL or the LGPL, and not to allow others to
  30  * use your version of this file under the terms of the MPL, indicate your
  31  * decision by deleting the provisions above and replace them with the notice
  32  * and other provisions required by the GPL or the LGPL. If you do not delete
  33  * the provisions above, a recipient may use your version of this file under
  34  * the terms of any one of the MPL, the GPL or the LGPL.
  35  *
  36  * ***** END LICENSE BLOCK ***** */
  37
  38 #ifndef nsIImage_h___
  39 #define nsIImage_h___
  40
  41 #include "nsISupports.h"
  42 #include "nsIRenderingContext.h"
  43 #include "nsRect.h"
  44 #include "gfxRect.h"
  45
  46 class gfxASurface;
  47 class gfxPattern;
  48
  49 class nsIDeviceContext;
  50
  51 struct nsColorMap
  52 {
  53   //I lifted this from the image lib. The difference is that
  54   //this uses nscolor instead of NI_RGB. Multiple color pollution
  55   //is a bad thing. MMP
  56   PRInt32 NumColors;  // Number of colors in the colormap.
  57                       // A negative value can be used to denote a
  58                       // possibly non-unique set.
  59   //nscolor *Map;       // Colormap colors.
  60   PRUint8 *Index;     // NULL, if map is in index order, otherwise
  61                       // specifies the indices of the map entries. */
  62 };
  63
  64 typedef enum {
  65     nsMaskRequirements_kNoMask,
  66     nsMaskRequirements_kNeeds1Bit,
  67     nsMaskRequirements_kNeeds8Bit
  68 } nsMaskRequirements;
  69
  70
  71 #define  nsImageUpdateFlags_kColorMapChanged 0x1
  72 #define  nsImageUpdateFlags_kBitsChanged     0x2
  73
  74 // IID for the nsIImage interface
  75 // 96d9d7ce-e575-4265-8507-35555112a430
  76 #define NS_IIMAGE_IID \
  77 { 0x96d9d7ce, 0xe575, 0x4265, \
  78   { 0x85, 0x07, 0x35, 0x55, 0x51, 0x12, 0xa4, 0x30 } }
  79
  80 // Interface to Images
  81 class nsIImage : public nsISupports
  82 {
  83
  84 public:
  85   NS_DECLARE_STATIC_IID_ACCESSOR(NS_IIMAGE_IID)
  86
  87   /**
  88    * Build and initialize the nsIImage
  89    * @param aWidth The width in pixels of the desired pixelmap
  90    * @param aHeight The height in pixels of the desired pixelmap
  91    * @param aDepth The number of bits per pixel for the pixelmap
  92    * @param aMaskRequirements A flag indicating if a alpha mask should be allocated
  93    */
  94   virtual nsresult Init(PRInt32 aWidth, PRInt32 aHeight, PRInt32 aDepth, nsMaskRequirements aMaskRequirements) = 0;
  95
  96   /**
  97    * Get the number of bytes per pixel for this image
  98    * @update - dwc 2/3/99
  99    * @return - the number of bytes per pixel
 100    */
 101   virtual PRInt32 GetBytesPix() = 0;
 102
 103   /**
 104    * Get whether rows are organized top to bottom, or bottom to top
 105    * @update - syd 3/29/99
 106    * @return PR_TRUE if top to bottom, else PR_FALSE
 107    */
 108   virtual PRBool GetIsRowOrderTopToBottom() = 0;
 109
 110   /**
 111    * Get the width for the pixelmap
 112    * @update - dwc 2/1/99
 113    * @return The width in pixels for the pixelmap
 114    */
 115   virtual PRInt32 GetWidth() = 0;
 116
 117   /**
 118    * Get the height for the pixelmap
 119    * @update - dwc 2/1/99
 120    * @return The height in pixels for the pixelmap
 121    */
 122   virtual PRInt32 GetHeight() = 0;
 123
 124   /**
 125    * Get a pointer to the bits for the pixelmap, only if it is not optimized
 126    * @update - dwc 2/1/99
 127    * @return address of the DIB pixel array
 128    */
 129   virtual PRUint8 * GetBits() = 0;
 130
 131   /**
 132    * Get the number of bytes needed to get to the next scanline for the pixelmap
 133    * @update - dwc 2/1/99
 134    * @return The number of bytes in each scanline
 135    */
 136   virtual PRInt32 GetLineStride() = 0;
 137
 138   /**
 139    * Get whether this image has an alpha mask. Preferable to testing
 140    * if GetAlphaBits() is non-null.
 141    * @update - sfraser 10/19/99
 142    * @return PR_TRUE if the image has an alpha mask, PR_FALSE otherwise
 143    */
 144   virtual PRBool GetHasAlphaMask() = 0;
 145
 146   /**
 147    * Get a pointer to the bits for the alpha mask
 148    * @update - dwc 2/1/99
 149    * @return address of the alpha mask pixel array
 150    */
 151   virtual PRUint8 * GetAlphaBits() = 0;
 152
 153   /**
 154    * Get the number of bytes per scanline for the alpha mask
 155    * @update - dwc 2/1/99
 156    * @return The number of bytes in each scanline
 157    */
 158   virtual PRInt32 GetAlphaLineStride() = 0;
 159
 160   /**
 161    * Update the nsIImage color table
 162    * @update - dougt 9/9/08
 163    * @param aFlags Used to pass in parameters for the update
 164    * @param aUpdateRect The rectangle to update
 165    * @return success code. failure means stop decoding
 166    */
 167   virtual nsresult ImageUpdated(nsIDeviceContext *aContext, PRUint8 aFlags, nsIntRect *aUpdateRect) = 0;
 168
 169   /**
 170    * Get whether this image's region is completely filled with data.
 171    * @return PR_TRUE if image is complete, PR_FALSE if image is not yet
 172    *         complete or broken
 173    */
 174   virtual PRBool GetIsImageComplete() = 0;
 175
 176   /**
 177    * Converted this pixelmap to an optimized pixelmap for the device
 178    * @update - dwc 2/1/99
 179    * @param aContext The device to optimize for
 180    * @return the result of the operation, if NS_OK, then the pixelmap is optimized
 181    */
 182   virtual nsresult Optimize(nsIDeviceContext* aContext) = 0;
 183
 184   /**
 185    * Get the colormap for the nsIImage
 186    * @update - dwc 2/1/99
 187    * @return if non null, the colormap for the pixelmap,otherwise the image is not color mapped
 188    */
 189   virtual nsColorMap * GetColorMap() = 0;
 190
 191   /**
 192    * BitBlit the nsIImage to a device, the source and dest can be scaled
 193    * @param aSourceRect  source rectangle, in image pixels
 194    * @param aSubimageRect the subimage that we're extracting the contents from.
 195    * It must contain aSourceRect. Pixels outside this rectangle must not
 196    * be sampled.
 197    * @param aDestRect  destination rectangle, in device pixels
 198    */
 199   NS_IMETHOD Draw(nsIRenderingContext &aContext,
 200                   const gfxRect &aSourceRect,
 201                   const gfxRect &aSubimageRect,
 202                   const gfxRect &aDestRect) = 0;
 203
 204   /**
 205    * Get the alpha depth for the image mask
 206    * @update - lordpixel 2001/05/16
 207    * @return  the alpha mask depth for the image, ie, 0, 1 or 8
 208    */
 209   virtual PRInt8 GetAlphaDepth() = 0;
 210
 211   /**
 212    * Return information about the bits for this structure
 213    * @update - dwc 2/1/99
 214    * @return a bitmap info structure for the Device Dependent Bits
 215    */
 216   virtual void* GetBitInfo() = 0;
 217
 218
 219   /**
 220    * LockImagePixels
 221    * Lock the image pixels so that we can access them directly,
 222    * with safety. May be a noop on some platforms.
 223    *
 224    * If you want to be able to call GetSurface(), wrap the call in
 225    * LockImagePixels()/UnlockImagePixels(). This also allows you to write to
 226    * the surface returned by GetSurface().
 227    *
 228    * aMaskPixels = PR_TRUE for the mask, PR_FALSE for the image
 229    *
 230    * Must be balanced by a call to UnlockImagePixels().
 231    *
 232    * @update - sfraser 10/18/99
 233    * @return error result
 234    */
 235   NS_IMETHOD LockImagePixels(PRBool aMaskPixels) = 0;
 236
 237   /**
 238    * UnlockImagePixels
 239    * Unlock the image pixels. May be a noop on some platforms.
 240    *
 241    * Should balance an earlier call to LockImagePixels().
 242    *
 243    * aMaskPixels = PR_TRUE for the mask, PR_FALSE for the image
 244    *
 245    * @update - sfraser 10/18/99
 246    * @return error result
 247    */
 248   NS_IMETHOD UnlockImagePixels(PRBool aMaskPixels) = 0;
 249
 250   /**
 251    * GetSurface
 252    * Return the Thebes gfxASurface in aSurface, if there is one. Should be
 253    * wrapped by LockImagePixels()/UnlockImagePixels().
 254    *
 255    * aSurface will be AddRef'd (as with most getters), so
 256    * getter_AddRefs should be used.
 257    */
 258   NS_IMETHOD GetSurface(gfxASurface **aSurface) = 0;
 259
 260   /**
 261    * GetSurface
 262    * Return the Thebes gfxPattern in aPattern. It is always possible to get a
 263    * gfxPattern (unlike the gfxASurface from GetSurface()).
 264    *
 265    * aPattern will be AddRef'd (as with most getters), so
 266    * getter_AddRefs should be used.
 267    */
 268   NS_IMETHOD GetPattern(gfxPattern **aPattern) = 0;
 269
 270   /**
 271    * SetHasNoAlpha
 272    *
 273    * Hint to the image that all the pixels are fully opaque, even if
 274    * the original format requested a 1-bit or 8-bit alpha mask
 275    */
 276   virtual void SetHasNoAlpha() = 0;
 277 };
 278
 279 NS_DEFINE_STATIC_IID_ACCESSOR(nsIImage, NS_IIMAGE_IID)
 280
 281 #endif