include/SDL_blendmode.h
author M Stoeckl <code@mstoeckl.com>
Tue, 14 Jul 2020 19:18:16 -0400
changeset 13948 830a4ce7456e
parent 13422 fd6a12de91c7
permissions -rw-r--r--
Reuse Wayland connection from availability check
     1 /*
     2   Simple DirectMedia Layer
     3   Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org>
     4 
     5   This software is provided 'as-is', without any express or implied
     6   warranty.  In no event will the authors be held liable for any damages
     7   arising from the use of this software.
     8 
     9   Permission is granted to anyone to use this software for any purpose,
    10   including commercial applications, and to alter it and redistribute it
    11   freely, subject to the following restrictions:
    12 
    13   1. The origin of this software must not be misrepresented; you must not
    14      claim that you wrote the original software. If you use this software
    15      in a product, an acknowledgment in the product documentation would be
    16      appreciated but is not required.
    17   2. Altered source versions must be plainly marked as such, and must not be
    18      misrepresented as being the original software.
    19   3. This notice may not be removed or altered from any source distribution.
    20 */
    21 
    22 /**
    23  *  \file SDL_blendmode.h
    24  *
    25  *  Header file declaring the SDL_BlendMode enumeration
    26  */
    27 
    28 #ifndef SDL_blendmode_h_
    29 #define SDL_blendmode_h_
    30 
    31 #include "begin_code.h"
    32 /* Set up for C function definitions, even when using C++ */
    33 #ifdef __cplusplus
    34 extern "C" {
    35 #endif
    36 
    37 /**
    38  *  \brief The blend mode used in SDL_RenderCopy() and drawing operations.
    39  */
    40 typedef enum
    41 {
    42     SDL_BLENDMODE_NONE = 0x00000000,     /**< no blending
    43                                               dstRGBA = srcRGBA */
    44     SDL_BLENDMODE_BLEND = 0x00000001,    /**< alpha blending
    45                                               dstRGB = (srcRGB * srcA) + (dstRGB * (1-srcA))
    46                                               dstA = srcA + (dstA * (1-srcA)) */
    47     SDL_BLENDMODE_ADD = 0x00000002,      /**< additive blending
    48                                               dstRGB = (srcRGB * srcA) + dstRGB
    49                                               dstA = dstA */
    50     SDL_BLENDMODE_MOD = 0x00000004,      /**< color modulate
    51                                               dstRGB = srcRGB * dstRGB
    52                                               dstA = dstA */
    53     SDL_BLENDMODE_MUL = 0x00000008,      /**< color multiply
    54                                               dstRGB = (srcRGB * dstRGB) + (dstRGB * (1-srcA))
    55                                               dstA = (srcA * dstA) + (dstA * (1-srcA)) */
    56     SDL_BLENDMODE_INVALID = 0x7FFFFFFF
    57 
    58     /* Additional custom blend modes can be returned by SDL_ComposeCustomBlendMode() */
    59 
    60 } SDL_BlendMode;
    61 
    62 /**
    63  *  \brief The blend operation used when combining source and destination pixel components
    64  */
    65 typedef enum
    66 {
    67     SDL_BLENDOPERATION_ADD              = 0x1,  /**< dst + src: supported by all renderers */
    68     SDL_BLENDOPERATION_SUBTRACT         = 0x2,  /**< dst - src : supported by D3D9, D3D11, OpenGL, OpenGLES */
    69     SDL_BLENDOPERATION_REV_SUBTRACT     = 0x3,  /**< src - dst : supported by D3D9, D3D11, OpenGL, OpenGLES */
    70     SDL_BLENDOPERATION_MINIMUM          = 0x4,  /**< min(dst, src) : supported by D3D11 */
    71     SDL_BLENDOPERATION_MAXIMUM          = 0x5   /**< max(dst, src) : supported by D3D11 */
    72 
    73 } SDL_BlendOperation;
    74 
    75 /**
    76  *  \brief The normalized factor used to multiply pixel components
    77  */
    78 typedef enum
    79 {
    80     SDL_BLENDFACTOR_ZERO                = 0x1,  /**< 0, 0, 0, 0 */
    81     SDL_BLENDFACTOR_ONE                 = 0x2,  /**< 1, 1, 1, 1 */
    82     SDL_BLENDFACTOR_SRC_COLOR           = 0x3,  /**< srcR, srcG, srcB, srcA */
    83     SDL_BLENDFACTOR_ONE_MINUS_SRC_COLOR = 0x4,  /**< 1-srcR, 1-srcG, 1-srcB, 1-srcA */
    84     SDL_BLENDFACTOR_SRC_ALPHA           = 0x5,  /**< srcA, srcA, srcA, srcA */
    85     SDL_BLENDFACTOR_ONE_MINUS_SRC_ALPHA = 0x6,  /**< 1-srcA, 1-srcA, 1-srcA, 1-srcA */
    86     SDL_BLENDFACTOR_DST_COLOR           = 0x7,  /**< dstR, dstG, dstB, dstA */
    87     SDL_BLENDFACTOR_ONE_MINUS_DST_COLOR = 0x8,  /**< 1-dstR, 1-dstG, 1-dstB, 1-dstA */
    88     SDL_BLENDFACTOR_DST_ALPHA           = 0x9,  /**< dstA, dstA, dstA, dstA */
    89     SDL_BLENDFACTOR_ONE_MINUS_DST_ALPHA = 0xA   /**< 1-dstA, 1-dstA, 1-dstA, 1-dstA */
    90 
    91 } SDL_BlendFactor;
    92 
    93 /**
    94  *  \brief Create a custom blend mode, which may or may not be supported by a given renderer
    95  *
    96  *  \param srcColorFactor source color factor
    97  *  \param dstColorFactor destination color factor
    98  *  \param colorOperation color operation
    99  *  \param srcAlphaFactor source alpha factor
   100  *  \param dstAlphaFactor destination alpha factor
   101  *  \param alphaOperation alpha operation
   102  *
   103  *  The result of the blend mode operation will be:
   104  *      dstRGB = dstRGB * dstColorFactor colorOperation srcRGB * srcColorFactor
   105  *  and
   106  *      dstA = dstA * dstAlphaFactor alphaOperation srcA * srcAlphaFactor
   107  */
   108 extern DECLSPEC SDL_BlendMode SDLCALL SDL_ComposeCustomBlendMode(SDL_BlendFactor srcColorFactor,
   109                                                                  SDL_BlendFactor dstColorFactor,
   110                                                                  SDL_BlendOperation colorOperation,
   111                                                                  SDL_BlendFactor srcAlphaFactor,
   112                                                                  SDL_BlendFactor dstAlphaFactor,
   113                                                                  SDL_BlendOperation alphaOperation);
   114 
   115 /* Ends C function definitions when using C++ */
   116 #ifdef __cplusplus
   117 }
   118 #endif
   119 #include "close_code.h"
   120 
   121 #endif /* SDL_blendmode_h_ */
   122 
   123 /* vi: set ts=4 sw=4 expandtab: */