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 "nsMargin.h"
  43 #include "nsRect.h"
  44
  45 class gfxASurface;
  46 class gfxPattern;
  47 class gfxMatrix;
  48 class gfxRect;
  49 class gfxContext;
  50
  51 class nsIDeviceContext;
  52
  53 struct nsColorMap
  54 {
  55   //I lifted this from the image lib. The difference is that
  56   //this uses nscolor instead of NI_RGB. Multiple color pollution
  57   //is a bad thing. MMP
  58   PRInt32 NumColors;  // Number of colors in the colormap.
  59                       // A negative value can be used to denote a
  60                       // possibly non-unique set.
  61   //nscolor *Map;       // Colormap colors.
  62   PRUint8 *Index;     // NULL, if map is in index order, otherwise
  63                       // specifies the indices of the map entries. */
  64 };
  65
  66 typedef enum {
  67     nsMaskRequirements_kNoMask,
  68     nsMaskRequirements_kNeeds1Bit,
  69     nsMaskRequirements_kNeeds8Bit
  70 } nsMaskRequirements;
  71
  72
  73 #define  nsImageUpdateFlags_kColorMapChanged 0x1
  74 #define  nsImageUpdateFlags_kBitsChanged     0x2
  75
  76 // IID for the nsIImage interface
  77 // 455fc276-01de-488f-9f8f-19b85a6b112d
  78 #define NS_IIMAGE_IID \
  79   { 0x455fc276, 0x01de, 0x488f, \
  80     { 0x9f, 0x8f, 0x19, 0xb8, 0x5a, 0x6b, 0x11, 0x2d } }
  81
  82 // Interface to Images
  83 class nsIImage : public nsISupports
  84 {
  85
  86 public:
  87   NS_DECLARE_STATIC_IID_ACCESSOR(NS_IIMAGE_IID)
  88
  89   /**
  90    * Build and initialize the nsIImage
  91    * @param aWidth The width in pixels of the desired pixelmap
  92    * @param aHeight The height in pixels of the desired pixelmap
  93    * @param aDepth The number of bits per pixel for the pixelmap
  94    * @param aMaskRequirements A flag indicating if a alpha mask should be allocated
  95    */
  96   virtual nsresult Init(PRInt32 aWidth, PRInt32 aHeight, PRInt32 aDepth, nsMaskRequirements aMaskRequirements) = 0;
  97
  98   /**
  99    * Get the number of bytes per pixel for this image
 100    * @update - dwc 2/3/99
 101    * @return - the number of bytes per pixel
 102    */
 103   virtual PRInt32 GetBytesPix() = 0;
 104
 105   /**
 106    * Get whether rows are organized top to bottom, or bottom to top
 107    * @update - syd 3/29/99
 108    * @return PR_TRUE if top to bottom, else PR_FALSE
 109    */
 110   virtual PRBool GetIsRowOrderTopToBottom() = 0;
 111
 112   /**
 113    * Get the width for the pixelmap
 114    * @update - dwc 2/1/99
 115    * @return The width in pixels for the pixelmap
 116    */
 117   virtual PRInt32 GetWidth() = 0;
 118
 119   /**
 120    * Get the height for the pixelmap
 121    * @update - dwc 2/1/99
 122    * @return The height in pixels for the pixelmap
 123    */
 124   virtual PRInt32 GetHeight() = 0;
 125
 126   /**
 127    * Get a pointer to the bits for the pixelmap, only if it is not optimized
 128    * @update - dwc 2/1/99
 129    * @return address of the DIB pixel array
 130    */
 131   virtual PRUint8 * GetBits() = 0;
 132
 133   /**
 134    * Get the number of bytes needed to get to the next scanline for the pixelmap
 135    * @update - dwc 2/1/99
 136    * @return The number of bytes in each scanline
 137    */
 138   virtual PRInt32 GetLineStride() = 0;
 139
 140   /**
 141    * Get whether this image has an alpha mask. Preferable to testing
 142    * if GetAlphaBits() is non-null.
 143    * @update - sfraser 10/19/99
 144    * @return PR_TRUE if the image has an alpha mask, PR_FALSE otherwise
 145    */
 146   virtual PRBool GetHasAlphaMask() = 0;
 147
 148   /**
 149    * Get a pointer to the bits for the alpha mask
 150    * @update - dwc 2/1/99
 151    * @return address of the alpha mask pixel array
 152    */
 153   virtual PRUint8 * GetAlphaBits() = 0;
 154
 155   /**
 156    * Get the number of bytes per scanline for the alpha mask
 157    * @update - dwc 2/1/99
 158    * @return The number of bytes in each scanline
 159    */
 160   virtual PRInt32 GetAlphaLineStride() = 0;
 161
 162   /**
 163    * Update the nsIImage color table
 164    * @update - dougt 9/9/08
 165    * @param aFlags Used to pass in parameters for the update
 166    * @param aUpdateRect The rectangle to update
 167    * @return success code. failure means stop decoding
 168    */
 169   virtual nsresult ImageUpdated(nsIDeviceContext *aContext, PRUint8 aFlags, nsIntRect *aUpdateRect) = 0;
 170
 171   /**
 172    * Get whether this image's region is completely filled with data.
 173    * @return PR_TRUE if image is complete, PR_FALSE if image is not yet
 174    *         complete or broken
 175    */
 176   virtual PRBool GetIsImageComplete() = 0;
 177
 178   /**
 179    * Converted this pixelmap to an optimized pixelmap for the device
 180    * @update - dwc 2/1/99
 181    * @param aContext The device to optimize for
 182    * @return the result of the operation, if NS_OK, then the pixelmap is optimized
 183    */
 184   virtual nsresult Optimize(nsIDeviceContext* aContext) = 0;
 185
 186   /**
 187    * Get the colormap for the nsIImage
 188    * @update - dwc 2/1/99
 189    * @return if non null, the colormap for the pixelmap,otherwise the image is not color mapped
 190    */
 191   virtual nsColorMap * GetColorMap() = 0;
 192
 193   /**
 194    * BitBlit the nsIImage to a device, the source and dest can be scaled.
 195    * @param aContext the destination
 196    * @param aUserSpaceToImageSpace the transform that maps user-space
 197    * coordinates to coordinates in (tiled, post-padding) image pixels
 198    * @param aFill the area to fill with tiled images
 199    * @param aPadding the padding to be added to this image before tiling,
 200    * in image pixels
 201    * @param aSubimage the subimage in padded+tiled image space that we're
 202    * extracting the contents from. Pixels outside this rectangle must not
 203    * be sampled.
 204    *
 205    * So this is supposed to
 206    * -- add aPadding transparent pixels around the image
 207    * -- use that image to tile the plane
 208    * -- replace everything outside the aSubimage region with the nearest
 209    * border pixel of that region (like EXTEND_PAD)
 210    * -- fill aFill with the image, using aImageSpaceToDeviceSpace as the
 211    * image-space-to-device-space transform
 212    */
 213   virtual void Draw(gfxContext*        aContext,
 214                     const gfxMatrix&   aUserSpaceToImageSpace,
 215                     const gfxRect&     aFill,
 216                     const nsIntMargin& aPadding,
 217                     const nsIntRect&   aSubimage) = 0;
 218
 219   /**
 220    * Get the alpha depth for the image mask
 221    * @update - lordpixel 2001/05/16
 222    * @return  the alpha mask depth for the image, ie, 0, 1 or 8
 223    */
 224   virtual PRInt8 GetAlphaDepth() = 0;
 225
 226   /**
 227    * Return information about the bits for this structure
 228    * @update - dwc 2/1/99
 229    * @return a bitmap info structure for the Device Dependent Bits
 230    */
 231   virtual void* GetBitInfo() = 0;
 232
 233
 234   /**
 235    * LockImagePixels
 236    * Lock the image pixels so that we can access them directly,
 237    * with safety. May be a noop on some platforms.
 238    *
 239    * If you want to be able to call GetSurface(), wrap the call in
 240    * LockImagePixels()/UnlockImagePixels(). This also allows you to write to
 241    * the surface returned by GetSurface().
 242    *
 243    * aMaskPixels = PR_TRUE for the mask, PR_FALSE for the image
 244    *
 245    * Must be balanced by a call to UnlockImagePixels().
 246    *
 247    * @update - sfraser 10/18/99
 248    * @return error result
 249    */
 250   NS_IMETHOD LockImagePixels(PRBool aMaskPixels) = 0;
 251
 252   /**
 253    * UnlockImagePixels
 254    * Unlock the image pixels. May be a noop on some platforms.
 255    *
 256    * Should balance an earlier call to LockImagePixels().
 257    *
 258    * aMaskPixels = PR_TRUE for the mask, PR_FALSE for the image
 259    *
 260    * @update - sfraser 10/18/99
 261    * @return error result
 262    */
 263   NS_IMETHOD UnlockImagePixels(PRBool aMaskPixels) = 0;
 264
 265   /**
 266    * GetSurface
 267    * Return the Thebes gfxASurface in aSurface, if there is one. Should be
 268    * wrapped by LockImagePixels()/UnlockImagePixels().
 269    *
 270    * aSurface will be AddRef'd (as with most getters), so
 271    * getter_AddRefs should be used.
 272    */
 273   NS_IMETHOD GetSurface(gfxASurface **aSurface) = 0;
 274
 275   /**
 276    * GetSurface
 277    * Return the Thebes gfxPattern in aPattern. It is always possible to get a
 278    * gfxPattern (unlike the gfxASurface from GetSurface()).
 279    *
 280    * aPattern will be AddRef'd (as with most getters), so
 281    * getter_AddRefs should be used.
 282    */
 283   NS_IMETHOD GetPattern(gfxPattern **aPattern) = 0;
 284
 285   /**
 286    * SetHasNoAlpha
 287    *
 288    * Hint to the image that all the pixels are fully opaque, even if
 289    * the original format requested a 1-bit or 8-bit alpha mask
 290    */
 291   virtual void SetHasNoAlpha() = 0;
 292 };
 293
 294 NS_DEFINE_STATIC_IID_ACCESSOR(nsIImage, NS_IIMAGE_IID)
 295
 296 #endif