Line data    Source code

       1             : /******************************************************************************
       2             :  *
       3             :  * Project:  GDAL
       4             :  * Purpose:  "blend" step of "raster pipeline"
       5             :  * Author:   Even Rouault <even dot rouault at spatialys.com>
       6             :  *
       7             :  ******************************************************************************
       8             :  * Copyright (c) 2025, Even Rouault <even dot rouault at spatialys.com>
       9             :  *
      10             :  * SPDX-License-Identifier: MIT
      11             :  ****************************************************************************/
      12             : 
      13             : #ifndef GDALALG_RASTER_BLEND_INCLUDED
      14             : #define GDALALG_RASTER_BLEND_INCLUDED
      15             : 
      16             : #include "gdalalg_raster_pipeline.h"
      17             : 
      18             : //! @cond Doxygen_Suppress
      19             : 
      20             : /************************************************************************/
      21             : /*                           CompositionMode                            */
      22             : /************************************************************************/
      23             : 
      24             : //! Blend composition modes (aka: operators)
      25             : enum class CompositionMode : unsigned
      26             : {
      27             :     SRC_OVER = 0,
      28             :     HSV_VALUE,
      29             :     MULTIPLY,
      30             :     SCREEN,
      31             :     OVERLAY,
      32             :     HARD_LIGHT,
      33             :     DARKEN,
      34             :     LIGHTEN,
      35             :     COLOR_DODGE,
      36             :     COLOR_BURN,
      37             : };
      38             : 
      39             : //! Returns a map of all composition modes to their string identifiers
      40             : std::map<CompositionMode, std::string> CompositionModes();
      41             : 
      42             : //! Returns the text identifier of the composition mode
      43             : std::string CompositionModeToString(CompositionMode mode);
      44             : 
      45             : //! Returns a list of all modes string identifiers
      46             : std::vector<std::string> CompositionModesIdentifiers();
      47             : 
      48             : //! Parses a composition mode from its string identifier
      49             : CompositionMode CompositionModeFromString(const std::string &str);
      50             : 
      51             : //! Returns the minimum number of bands required for the given composition mode
      52             : int MinBandCountForCompositionMode(CompositionMode mode);
      53             : 
      54             : /**
      55             :  *  Returns the maximum number of bands allowed for the given composition mode
      56             :  *  (-1 means no limit)
      57             :  */
      58             : int MaxBandCountForCompositionMode(CompositionMode mode);
      59             : 
      60             : //! Checks whether the number of bands is compatible with the given composition mode
      61             : bool BandCountIsCompatibleWithCompositionMode(int bandCount,
      62             :                                               CompositionMode mode);
      63             : 
      64             : /************************************************************************/
      65             : /*                       GDALRasterBlendAlgorithm                       */
      66             : /************************************************************************/
      67             : 
      68             : class GDALRasterBlendAlgorithm /* non final*/
      69             :     : public GDALRasterPipelineStepAlgorithm
      70             : {
      71             :   public:
      72             :     explicit GDALRasterBlendAlgorithm(bool standaloneStep = false);
      73             : 
      74             :     static constexpr const char *NAME = "blend";
      75             :     static constexpr const char *DESCRIPTION =
      76             :         "Blend/compose two raster datasets";
      77             :     static constexpr const char *HELP_URL = "/programs/gdal_raster_blend.html";
      78             : 
      79             :   private:
      80             :     bool RunStep(GDALPipelineStepRunContext &ctxt) override;
      81             :     bool ValidateGlobal();
      82             : 
      83             :     GDALArgDatasetValue m_overlayDataset{};
      84             :     CompositionMode m_operator{};
      85             :     std::string m_operatorIdentifier{};
      86             :     static constexpr int OPACITY_INPUT_RANGE = 100;
      87             :     int m_opacity = OPACITY_INPUT_RANGE;
      88             :     std::unique_ptr<GDALDataset, GDALDatasetUniquePtrReleaser> m_poTmpSrcDS{};
      89             :     std::unique_ptr<GDALDataset, GDALDatasetUniquePtrReleaser>
      90             :         m_poTmpOverlayDS{};
      91             : };
      92             : 
      93             : /************************************************************************/
      94             : /*                  GDALRasterBlendAlgorithmStandalone                  */
      95             : /************************************************************************/
      96             : 
      97         372 : class GDALRasterBlendAlgorithmStandalone final : public GDALRasterBlendAlgorithm
      98             : {
      99             :   public:
     100         186 :     GDALRasterBlendAlgorithmStandalone()
     101         186 :         : GDALRasterBlendAlgorithm(/* standaloneStep = */ true)
     102             :     {
     103         186 :     }
     104             : 
     105             :     ~GDALRasterBlendAlgorithmStandalone() override;
     106             : };
     107             : 
     108             : //! @endcond
     109             : 
     110             : #endif /* GDALALG_RASTER_COLOR_MERGE_INCLUDED */