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Add SDL_blendmode.inc
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‎units/SDL_blendmode.inc‎

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{
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This file is part of:
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SDL3 for Pascal
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(https://github.com/PascalGameDevelopment/SDL3-for-Pascal)
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SPDX-License-Identifier: Zlib
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}
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{*
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* A set of blend modes used in drawing operations.
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*
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* These predefined blend modes are supported everywhere.
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*
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* Additional values may be obtained from SDL_ComposeCustomBlendMode.
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*
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* \since This datatype is available since SDL 3.1.3.
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*
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* \sa SDL_ComposeCustomBlendMode
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}
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type
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PPSDL_BlendMode = ^PSDL_BlendMode;
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PSDL_BlendMode = ^TSDL_BlendMode;
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TSDL_BlendMode = cuint32;
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const
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SDL_BLENDMODE_NONE = TSDL_BlendMode($00000000); {*< no blending: dstRGBA = srcRGBA }
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SDL_BLENDMODE_BLEND = TSDL_BlendMode($00000001); {*< alpha blending: dstRGB = (srcRGB * srcA) + (dstRGB * (1-srcA)), dstA = srcA + (dstA * (1-srcA)) }
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SDL_BLENDMODE_BLEND_PREMULTIPLIED = TSDL_BlendMode($00000010); {*< pre-multiplied alpha blending: dstRGBA = srcRGBA + (dstRGBA * (1-srcA)) }
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SDL_BLENDMODE_ADD = TSDL_BlendMode($00000002); {*< additive blending: dstRGB = (srcRGB * srcA) + dstRGB, dstA = dstA }
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SDL_BLENDMODE_ADD_PREMULTIPLIED = TSDL_BlendMode($00000020); {*< pre-multiplied additive blending: dstRGB = srcRGB + dstRGB, dstA = dstA }
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SDL_BLENDMODE_MOD = TSDL_BlendMode($00000004); {*< color modulate: dstRGB = srcRGB * dstRGB, dstA = dstA }
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SDL_BLENDMODE_MUL = TSDL_BlendMode($00000008); {*< color multiply: dstRGB = (srcRGB * dstRGB) + (dstRGB * (1-srcA)), dstA = dstA }
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SDL_BLENDMODE_INVALID = TSDL_BlendMode($7FFFFFFF);
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{*
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* The blend operation used when combining source and destination pixel
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* components.
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*
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* \since This enum is available since SDL 3.1.3.
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}
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type
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PPSDL_BlendOperation = ^PSDL_BlendOperation;
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PSDL_BlendOperation = ^TSDL_BlendOperation;
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TSDL_BlendOperation = Integer;
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const
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SDL_BLENDOPERATION_ADD = TSDL_BlendOperation($1); {*< dst + src: supported by all renderers }
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SDL_BLENDOPERATION_SUBTRACT = TSDL_BlendOperation($2); {*< src - dst: supported by D3D, OpenGL, OpenGLES, and Vulkan }
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SDL_BLENDOPERATION_REV_SUBTRACT = TSDL_BlendOperation($3); {*< dst - src: supported by D3D, OpenGL, OpenGLES, and Vulkan }
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SDL_BLENDOPERATION_MINIMUM = TSDL_BlendOperation($4); {*< min(dst, src): supported by D3D, OpenGL, OpenGLES, and Vulkan }
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SDL_BLENDOPERATION_MAXIMUM = TSDL_BlendOperation($5); {*< max(dst, src): supported by D3D, OpenGL, OpenGLES, and Vulkan }
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{*
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* The normalized factor used to multiply pixel components.
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*
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* The blend factors are multiplied with the pixels from a drawing operation
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* (src) and the pixels from the render target (dst) before the blend
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* operation. The comma-separated factors listed above are always applied in
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* the component order red, green, blue, and alpha.
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*
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* \since This enum is available since SDL 3.1.3.
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}
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type
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PPSDL_BlendFactor = ^PSDL_BlendFactor;
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PSDL_BlendFactor = ^TSDL_BlendFactor;
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TSDL_BlendFactor = Integer;
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const
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SDL_BLENDFACTOR_ZERO = TSDL_BlendFactor($1); {*< 0, 0, 0, 0 }
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SDL_BLENDFACTOR_ONE = TSDL_BlendFactor($2); {*< 1, 1, 1, 1 }
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SDL_BLENDFACTOR_SRC_COLOR = TSDL_BlendFactor($3); {*< srcR, srcG, srcB, srcA }
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SDL_BLENDFACTOR_ONE_MINUS_SRC_COLOR = TSDL_BlendFactor($4); {*< 1-srcR, 1-srcG, 1-srcB, 1-srcA }
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SDL_BLENDFACTOR_SRC_ALPHA = TSDL_BlendFactor($5); {*< srcA, srcA, srcA, srcA }
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SDL_BLENDFACTOR_ONE_MINUS_SRC_ALPHA = TSDL_BlendFactor($6); {*< 1-srcA, 1-srcA, 1-srcA, 1-srcA }
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SDL_BLENDFACTOR_DST_COLOR = TSDL_BlendFactor($7); {*< dstR, dstG, dstB, dstA }
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SDL_BLENDFACTOR_ONE_MINUS_DST_COLOR = TSDL_BlendFactor($8); {*< 1-dstR, 1-dstG, 1-dstB, 1-dstA }
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SDL_BLENDFACTOR_DST_ALPHA = TSDL_BlendFactor($9); {*< dstA, dstA, dstA, dstA }
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SDL_BLENDFACTOR_ONE_MINUS_DST_ALPHA = TSDL_BlendFactor($A); {*< 1-dstA, 1-dstA, 1-dstA, 1-dstA }
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{*
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* Compose a custom blend mode for renderers.
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*
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* The functions SDL_SetRenderDrawBlendMode and SDL_SetTextureBlendMode accept
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* the SDL_BlendMode returned by this function if the renderer supports it.
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*
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* A blend mode controls how the pixels from a drawing operation (source) get
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* combined with the pixels from the render target (destination). First, the
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* components of the source and destination pixels get multiplied with their
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* blend factors. Then, the blend operation takes the two products and
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* calculates the result that will get stored in the render target.
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*
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* Expressed in pseudocode, it would look like this:
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*
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* ```c
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* dstRGB = colorOperation(srcRGB * srcColorFactor, dstRGB * dstColorFactor);
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* dstA = alphaOperation(srcA * srcAlphaFactor, dstA * dstAlphaFactor);
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* ```
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*
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* Where the functions `colorOperation(src, dst)` and `alphaOperation(src,
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* dst)` can return one of the following:
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*
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* - `src + dst`
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* - `src - dst`
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* - `dst - src`
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* - `min(src, dst)`
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* - `max(src, dst)`
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*
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* The red, green, and blue components are always multiplied with the first,
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* second, and third components of the SDL_BlendFactor, respectively. The
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* fourth component is not used.
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*
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* The alpha component is always multiplied with the fourth component of the
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* SDL_BlendFactor. The other components are not used in the alpha
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* calculation.
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*
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* Support for these blend modes varies for each renderer. To check if a
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* specific SDL_BlendMode is supported, create a renderer and pass it to
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* either SDL_SetRenderDrawBlendMode or SDL_SetTextureBlendMode. They will
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* return with an error if the blend mode is not supported.
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*
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* This list describes the support of custom blend modes for each renderer.
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* All renderers support the four blend modes listed in the SDL_BlendMode
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* enumeration.
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*
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* - **direct3d**: Supports all operations with all factors. However, some
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* factors produce unexpected results with `SDL_BLENDOPERATION_MINIMUM` and
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* `SDL_BLENDOPERATION_MAXIMUM`.
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* - **direct3d11**: Same as Direct3D 9.
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* - **opengl**: Supports the `SDL_BLENDOPERATION_ADD` operation with all
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* factors. OpenGL versions 1.1, 1.2, and 1.3 do not work correctly here.
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* - **opengles2**: Supports the `SDL_BLENDOPERATION_ADD`,
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* `SDL_BLENDOPERATION_SUBTRACT`, `SDL_BLENDOPERATION_REV_SUBTRACT`
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* operations with all factors.
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* - **psp**: No custom blend mode support.
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* - **software**: No custom blend mode support.
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*
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* Some renderers do not provide an alpha component for the default render
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* target. The `SDL_BLENDFACTOR_DST_ALPHA` and
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* `SDL_BLENDFACTOR_ONE_MINUS_DST_ALPHA` factors do not have an effect in this
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* case.
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*
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* \param srcColorFactor the SDL_BlendFactor applied to the red, green, and
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* blue components of the source pixels.
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* \param dstColorFactor the SDL_BlendFactor applied to the red, green, and
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* blue components of the destination pixels.
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* \param colorOperation the SDL_BlendOperation used to combine the red,
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* green, and blue components of the source and
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* destination pixels.
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* \param srcAlphaFactor the SDL_BlendFactor applied to the alpha component of
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* the source pixels.
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* \param dstAlphaFactor the SDL_BlendFactor applied to the alpha component of
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* the destination pixels.
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* \param alphaOperation the SDL_BlendOperation used to combine the alpha
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* component of the source and destination pixels.
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* \returns an SDL_BlendMode that represents the chosen factors and
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* operations.
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*
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* \threadsafety It is safe to call this function from any thread.
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*
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* \since This function is available since SDL 3.1.3.
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*
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* \sa SDL_SetRenderDrawBlendMode
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* \sa SDL_GetRenderDrawBlendMode
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* \sa SDL_SetTextureBlendMode
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* \sa SDL_GetTextureBlendMode
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}
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function SDL_ComposeCustomBlendMode(
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srcColorFactor: TSDL_BlendFactor;
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dstColorFactor: TSDL_BlendFactor;
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colorOperation: TSDL_BlendOperation;
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srcAlphaFactor: TSDL_BlendFactor;
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dstAlphaFactor: TSDL_BlendFactor;
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alphaOperation: TSDL_BlendOperation): TSDL_BlendMode; cdecl;
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external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_ComposeCustomBlendMode' {$ENDIF} {$ENDIF};
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