gfx/2d/DataSurfaceHelpers.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef _MOZILLA_GFX_DATASURFACEHELPERS_H
   8 #define _MOZILLA_GFX_DATASURFACEHELPERS_H
   9
  10 #include "2D.h"
  11
  12 #include "mozilla/UniquePtr.h"
  13
  14 namespace mozilla {
  15 namespace gfx {
  16
  17 int32_t StrideForFormatAndWidth(SurfaceFormat aFormat, int32_t aWidth);
  18
  19 /**
  20  * Create a DataSourceSurface and init the surface with the |aData|. The stride
  21  * of this source surface might be different from the input data's
  22  * |aDataStride|. System will try to use the optimal one.
  23  */
  24 already_AddRefed<DataSourceSurface> CreateDataSourceSurfaceFromData(
  25     const IntSize& aSize, SurfaceFormat aFormat, const uint8_t* aData,
  26     int32_t aDataStride);
  27
  28 /**
  29  * Similar to CreateDataSourceSurfaceFromData(), but could setup the stride for
  30  * this surface.
  31  */
  32 already_AddRefed<DataSourceSurface> CreateDataSourceSurfaceWithStrideFromData(
  33     const IntSize& aSize, SurfaceFormat aFormat, int32_t aStride,
  34     const uint8_t* aData, int32_t aDataStride);
  35
  36 /**
  37  * Copy the pixel data from aSrc and pack it into aDst. aSrcSize, aSrcStride
  38  * and aBytesPerPixel give the size, stride and bytes per pixel for aSrc's
  39  * surface. Callers are responsible for making sure that aDst is big enough to
  40  * contain |aSrcSize.width * aSrcSize.height * aBytesPerPixel| bytes.
  41  */
  42 void CopySurfaceDataToPackedArray(uint8_t* aSrc, uint8_t* aDst,
  43                                   IntSize aSrcSize, int32_t aSrcStride,
  44                                   int32_t aBytesPerPixel);
  45
  46 /**
  47  * Convert aSurface to a packed buffer in BGRA format.
  48  */
  49 UniquePtr<uint8_t[]> SurfaceToPackedBGRA(DataSourceSurface* aSurface);
  50
  51 /**
  52  * Convert aSurface to a packed buffer in BGR format. The pixel data is
  53  * returned in a buffer allocated with new uint8_t[]. The caller then has
  54  * ownership of the buffer and is responsible for delete[]'ing it.
  55  *
  56  * This function is currently only intended for use with surfaces of format
  57  * SurfaceFormat::B8G8R8X8 since the X components of the pixel data (if any)
  58  * are simply dropped (no attempt is made to un-pre-multiply alpha from the
  59  * color components).
  60  */
  61 uint8_t* SurfaceToPackedBGR(DataSourceSurface* aSurface);
  62
  63 /**
  64  * Clears all the bytes in a DataSourceSurface's data array to zero (so to
  65  * transparent black for SurfaceFormat::B8G8R8A8, for example).
  66  * Note that DataSourceSurfaces can be initialized to zero, which is
  67  * more efficient than zeroing the surface after initialization.
  68  */
  69 void ClearDataSourceSurface(DataSourceSurface* aSurface);
  70
  71 /**
  72  * Multiplies aStride and aHeight and makes sure the result is limited to
  73  * something sane. To keep things consistent, this should always be used
  74  * wherever we allocate a buffer based on surface stride and height.
  75  *
  76  * @param aExtra Optional argument to specify an additional number of trailing
  77  *   bytes (useful for creating intermediate surfaces for filters, for
  78  *   example).
  79  *
  80  * @return The result of the multiplication if it is acceptable, or else zero.
  81  */
  82 size_t BufferSizeFromStrideAndHeight(int32_t aStride, int32_t aHeight,
  83                                      int32_t aExtraBytes = 0);
  84
  85 /**
  86  * Multiplies aWidth, aHeight, aDepth and makes sure the result is limited to
  87  * something sane. To keep things consistent, this should always be used
  88  * wherever we allocate a buffer based on surface dimensions.
  89  *
  90  * @param aExtra Optional argument to specify an additional number of trailing
  91  *   bytes (useful for creating intermediate surfaces for filters, for
  92  *   example).
  93  *
  94  * @return The result of the multiplication if it is acceptable, or else zero.
  95  */
  96 size_t BufferSizeFromDimensions(int32_t aWidth, int32_t aHeight, int32_t aDepth,
  97                                 int32_t aExtraBytes = 0);
  98 /**
  99  * Copy aSrcRect from aSrc to aDest starting at aDestPoint.
 100  * @returns false if the copy is not successful or the aSrc's size is empty.
 101  */
 102 bool CopyRect(DataSourceSurface* aSrc, DataSourceSurface* aDest,
 103               IntRect aSrcRect, IntPoint aDestPoint);
 104
 105 /**
 106  * Create a non aliasing copy of aSource. This creates a new DataSourceSurface
 107  * using the factory and copies the bits.
 108  *
 109  * @return a dss allocated by Factory that contains a copy a aSource.
 110  */
 111 already_AddRefed<DataSourceSurface> CreateDataSourceSurfaceByCloning(
 112     DataSourceSurface* aSource);
 113
 114 /**
 115  * Return the byte at aPoint.
 116  */
 117 uint8_t* DataAtOffset(DataSourceSurface* aSurface,
 118                       const DataSourceSurface::MappedSurface* aMap,
 119                       IntPoint aPoint);
 120
 121 /**
 122  * Check if aPoint is contained by the surface.
 123  *
 124  * @returns true if and only if aPoint is inside the surface.
 125  */
 126 bool SurfaceContainsPoint(SourceSurface* aSurface, const IntPoint& aPoint);
 127
 128 }  // namespace gfx
 129 }  // namespace mozilla
 130
 131 #endif  // _MOZILLA_GFX_DATASURFACEHELPERS_H