sdl2_frt/include/SDL_render.h

/*
  Simple DirectMedia Layer
  Copyright (C) 1997-2021 Sam Lantinga <slouken@libsdl.org>

  This software is provided 'as-is', without any express or implied
  warranty.  In no event will the authors be held liable for any damages
  arising from the use of this software.

  Permission is granted to anyone to use this software for any purpose,
  including commercial applications, and to alter it and redistribute it
  freely, subject to the following restrictions:

  1. The origin of this software must not be misrepresented; you must not
     claim that you wrote the original software. If you use this software
     in a product, an acknowledgment in the product documentation would be
     appreciated but is not required.
  2. Altered source versions must be plainly marked as such, and must not be
     misrepresented as being the original software.
  3. This notice may not be removed or altered from any source distribution.
*/

/**
 *  \file SDL_render.h
 *
 *  Header file for SDL 2D rendering functions.
 *
 *  This API supports the following features:
 *      * single pixel points
 *      * single pixel lines
 *      * filled rectangles
 *      * texture images
 *
 *  The primitives may be drawn in opaque, blended, or additive modes.
 *
 *  The texture images may be drawn in opaque, blended, or additive modes.
 *  They can have an additional color tint or alpha modulation applied to
 *  them, and may also be stretched with linear interpolation.
 *
 *  This API is designed to accelerate simple 2D operations. You may
 *  want more functionality such as polygons and particle effects and
 *  in that case you should use SDL's OpenGL/Direct3D support or one
 *  of the many good 3D engines.
 *
 *  These functions must be called from the main thread.
 *  See this bug for details: http://bugzilla.libsdl.org/show_bug.cgi?id=1995
 */

#ifndef SDL_render_h_
#define SDL_render_h_

#include "SDL_stdinc.h"
#include "SDL_rect.h"
#include "SDL_video.h"

#include "begin_code.h"
/* Set up for C function definitions, even when using C++ */
#ifdef __cplusplus
extern "C" {
#endif

/**
 * Flags used when creating a rendering context
 */
typedef enum
{
    SDL_RENDERER_SOFTWARE = 0x00000001,         /**< The renderer is a software fallback */
    SDL_RENDERER_ACCELERATED = 0x00000002,      /**< The renderer uses hardware
                                                     acceleration */
    SDL_RENDERER_PRESENTVSYNC = 0x00000004,     /**< Present is synchronized
                                                     with the refresh rate */
    SDL_RENDERER_TARGETTEXTURE = 0x00000008     /**< The renderer supports
                                                     rendering to texture */
} SDL_RendererFlags;

/**
 * Information on the capabilities of a render driver or context.
 */
typedef struct SDL_RendererInfo
{
    const char *name;           /**< The name of the renderer */
    Uint32 flags;               /**< Supported ::SDL_RendererFlags */
    Uint32 num_texture_formats; /**< The number of available texture formats */
    Uint32 texture_formats[16]; /**< The available texture formats */
    int max_texture_width;      /**< The maximum texture width */
    int max_texture_height;     /**< The maximum texture height */
} SDL_RendererInfo;

/**
 * The scaling mode for a texture.
 */
typedef enum
{
    SDL_ScaleModeNearest, /**< nearest pixel sampling */
    SDL_ScaleModeLinear,  /**< linear filtering */
    SDL_ScaleModeBest     /**< anisotropic filtering */
} SDL_ScaleMode;

/**
 * The access pattern allowed for a texture.
 */
typedef enum
{
    SDL_TEXTUREACCESS_STATIC,    /**< Changes rarely, not lockable */
    SDL_TEXTUREACCESS_STREAMING, /**< Changes frequently, lockable */
    SDL_TEXTUREACCESS_TARGET     /**< Texture can be used as a render target */
} SDL_TextureAccess;

/**
 * The texture channel modulation used in SDL_RenderCopy().
 */
typedef enum
{
    SDL_TEXTUREMODULATE_NONE = 0x00000000,     /**< No modulation */
    SDL_TEXTUREMODULATE_COLOR = 0x00000001,    /**< srcC = srcC * color */
    SDL_TEXTUREMODULATE_ALPHA = 0x00000002     /**< srcA = srcA * alpha */
} SDL_TextureModulate;

/**
 * Flip constants for SDL_RenderCopyEx
 */
typedef enum
{
    SDL_FLIP_NONE = 0x00000000,     /**< Do not flip */
    SDL_FLIP_HORIZONTAL = 0x00000001,    /**< flip horizontally */
    SDL_FLIP_VERTICAL = 0x00000002     /**< flip vertically */
} SDL_RendererFlip;

/**
 * A structure representing rendering state
 */
struct SDL_Renderer;
typedef struct SDL_Renderer SDL_Renderer;

/**
 * An efficient driver-specific representation of pixel data
 */
struct SDL_Texture;
typedef struct SDL_Texture SDL_Texture;


/* Function prototypes */

/**
 * Get the number of 2D rendering drivers available for the current display.
 *
 * A render driver is a set of code that handles rendering and texture
 * management on a particular display. Normally there is only one, but some
 * drivers may have several available with different capabilities.
 *
 * There may be none if SDL was compiled without render support.
 *
 * \returns a number >= 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \since This function is available since SDL 2.0.0.
 *
 * \sa SDL_CreateRenderer
 * \sa SDL_GetRenderDriverInfo
 */
extern DECLSPEC int SDLCALL SDL_GetNumRenderDrivers(void);

/**
 * Get info about a specific 2D rendering driver for the current display.
 *
 * \param index the index of the driver to query information about
 * \param info an SDL_RendererInfo structure to be filled with information on
 *             the rendering driver
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_CreateRenderer
 * \sa SDL_GetNumRenderDrivers
 */
extern DECLSPEC int SDLCALL SDL_GetRenderDriverInfo(int index,
                                                    SDL_RendererInfo * info);

/**
 * Create a window and default renderer.
 *
 * \param width the width of the window
 * \param height the height of the window
 * \param window_flags the flags used to create the window (see
 *                     SDL_CreateWindow())
 * \param window a pointer filled with the window, or NULL on error
 * \param renderer a pointer filled with the renderer, or NULL on error
 * \returns 0 on success, or -1 on error; call SDL_GetError() for more
 *          information.
 *
 * \sa SDL_CreateRenderer
 * \sa SDL_CreateWindow
 */
extern DECLSPEC int SDLCALL SDL_CreateWindowAndRenderer(
                                int width, int height, Uint32 window_flags,
                                SDL_Window **window, SDL_Renderer **renderer);


/**
 * Create a 2D rendering context for a window.
 *
 * \param window the window where rendering is displayed
 * \param index the index of the rendering driver to initialize, or -1 to
 *              initialize the first one supporting the requested flags
 * \param flags 0, or one or more SDL_RendererFlags OR'd together
 * \returns a valid rendering context or NULL if there was an error; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_CreateSoftwareRenderer
 * \sa SDL_DestroyRenderer
 * \sa SDL_GetNumRenderDrivers
 * \sa SDL_GetRendererInfo
 */
extern DECLSPEC SDL_Renderer * SDLCALL SDL_CreateRenderer(SDL_Window * window,
                                               int index, Uint32 flags);

/**
 * Create a 2D software rendering context for a surface.
 *
 * Two other API which can be used to create SDL_Renderer:
 * SDL_CreateRenderer() and SDL_CreateWindowAndRenderer(). These can _also_
 * create a software renderer, but they are intended to be used with an
 * SDL_Window as the final destination and not an SDL_Surface.
 *
 * \param surface the SDL_Surface structure representing the surface where
 *                rendering is done
 * \returns a valid rendering context or NULL if there was an error; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_CreateRenderer
 * \sa SDL_CreateWindowRenderer
 * \sa SDL_DestroyRenderer
 */
extern DECLSPEC SDL_Renderer * SDLCALL SDL_CreateSoftwareRenderer(SDL_Surface * surface);

/**
 * Get the renderer associated with a window.
 *
 * \param window the window to query
 * \returns the rendering context on success or NULL on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_CreateRenderer
 */
extern DECLSPEC SDL_Renderer * SDLCALL SDL_GetRenderer(SDL_Window * window);

/**
 * Get information about a rendering context.
 *
 * \param renderer the rendering context
 * \param info an SDL_RendererInfo structure filled with information about the
 *             current renderer
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_CreateRenderer
 */
extern DECLSPEC int SDLCALL SDL_GetRendererInfo(SDL_Renderer * renderer,
                                                SDL_RendererInfo * info);

/**
 * Get the output size in pixels of a rendering context.
 *
 * Due to high-dpi displays, you might end up with a rendering context that
 * has more pixels than the window that contains it, so use this instead of
 * SDL_GetWindowSize() to decide how much drawing area you have.
 *
 * \param renderer the rendering context
 * \param w an int filled with the width
 * \param h an int filled with the height
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \since This function is available since SDL 2.0.0.
 *
 * \sa SDL_GetRenderer
 */
extern DECLSPEC int SDLCALL SDL_GetRendererOutputSize(SDL_Renderer * renderer,
                                                      int *w, int *h);

/**
 * Create a texture for a rendering context.
 *
 * You can set the texture scaling method by setting
 * `SDL_HINT_RENDER_SCALE_QUALITY` before creating the texture.
 *
 * \param renderer the rendering context
 * \param format one of the enumerated values in SDL_PixelFormatEnum
 * \param access one of the enumerated values in SDL_TextureAccess
 * \param w the width of the texture in pixels
 * \param h the height of the texture in pixels
 * \returns a pointer to the created texture or NULL if no rendering context
 *          was active, the format was unsupported, or the width or height
 *          were out of range; call SDL_GetError() for more information.
 *
 * \sa SDL_CreateTextureFromSurface
 * \sa SDL_DestroyTexture
 * \sa SDL_QueryTexture
 * \sa SDL_UpdateTexture
 */
extern DECLSPEC SDL_Texture * SDLCALL SDL_CreateTexture(SDL_Renderer * renderer,
                                                        Uint32 format,
                                                        int access, int w,
                                                        int h);

/**
 * Create a texture from an existing surface.
 *
 * The surface is not modified or freed by this function.
 *
 * The SDL_TextureAccess hint for the created texture is
 * `SDL_TEXTUREACCESS_STATIC`.
 *
 * The pixel format of the created texture may be different from the pixel
 * format of the surface. Use SDL_QueryTexture() to query the pixel format of
 * the texture.
 *
 * \param renderer the rendering context
 * \param surface the SDL_Surface structure containing pixel data used to fill
 *                the texture
 * \returns the created texture or NULL on failure; call SDL_GetError() for
 *          more information.
 *
 * \sa SDL_CreateTexture
 * \sa SDL_DestroyTexture
 * \sa SDL_QueryTexture
 */
extern DECLSPEC SDL_Texture * SDLCALL SDL_CreateTextureFromSurface(SDL_Renderer * renderer, SDL_Surface * surface);

/**
 * Query the attributes of a texture.
 *
 * \param texture the texture to query
 * \param format a pointer filled in with the raw format of the texture; the
 *               actual format may differ, but pixel transfers will use this
 *               format (one of the SDL_PixelFormatEnum values)
 * \param access a pointer filled in with the actual access to the texture
 *               (one of the SDL_TextureAccess values)
 * \param w a pointer filled in with the width of the texture in pixels
 * \param h a pointer filled in with the height of the texture in pixels
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_CreateTexture
 */
extern DECLSPEC int SDLCALL SDL_QueryTexture(SDL_Texture * texture,
                                             Uint32 * format, int *access,
                                             int *w, int *h);

/**
 * Set an additional color value multiplied into render copy operations.
 *
 * When this texture is rendered, during the copy operation each source color
 * channel is modulated by the appropriate color value according to the
 * following formula:
 *
 * `srcC = srcC * (color / 255)`
 *
 * Color modulation is not always supported by the renderer; it will return -1
 * if color modulation is not supported.
 *
 * \param texture the texture to update
 * \param r the red color value multiplied into copy operations
 * \param g the green color value multiplied into copy operations
 * \param b the blue color value multiplied into copy operations
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_GetTextureColorMod
 * \sa SDL_SetTextureAlphaMod
 */
extern DECLSPEC int SDLCALL SDL_SetTextureColorMod(SDL_Texture * texture,
                                                   Uint8 r, Uint8 g, Uint8 b);


/**
 * Get the additional color value multiplied into render copy operations.
 *
 * \param texture the texture to query
 * \param r a pointer filled in with the current red color value
 * \param g a pointer filled in with the current green color value
 * \param b a pointer filled in with the current blue color value
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_GetTextureAlphaMod
 * \sa SDL_SetTextureColorMod
 */
extern DECLSPEC int SDLCALL SDL_GetTextureColorMod(SDL_Texture * texture,
                                                   Uint8 * r, Uint8 * g,
                                                   Uint8 * b);

/**
 * Set an additional alpha value multiplied into render copy operations.
 *
 * When this texture is rendered, during the copy operation the source alpha
 * value is modulated by this alpha value according to the following formula:
 *
 * `srcA = srcA * (alpha / 255)`
 *
 * Alpha modulation is not always supported by the renderer; it will return -1
 * if alpha modulation is not supported.
 *
 * \param texture the texture to update
 * \param alpha the source alpha value multiplied into copy operations
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_GetTextureAlphaMod
 * \sa SDL_SetTextureColorMod
 */
extern DECLSPEC int SDLCALL SDL_SetTextureAlphaMod(SDL_Texture * texture,
                                                   Uint8 alpha);

/**
 * Get the additional alpha value multiplied into render copy operations.
 *
 * \param texture the texture to query
 * \param alpha a pointer filled in with the current alpha value
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_GetTextureColorMod
 * \sa SDL_SetTextureAlphaMod
 */
extern DECLSPEC int SDLCALL SDL_GetTextureAlphaMod(SDL_Texture * texture,
                                                   Uint8 * alpha);

/**
 * Set the blend mode for a texture, used by SDL_RenderCopy().
 *
 * If the blend mode is not supported, the closest supported mode is chosen
 * and this function returns -1.
 *
 * \param texture the texture to update
 * \param blendMode the SDL_BlendMode to use for texture blending
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_GetTextureBlendMode
 * \sa SDL_RenderCopy
 */
extern DECLSPEC int SDLCALL SDL_SetTextureBlendMode(SDL_Texture * texture,
                                                    SDL_BlendMode blendMode);

/**
 * Get the blend mode used for texture copy operations.
 *
 * \param texture the texture to query
 * \param blendMode a pointer filled in with the current SDL_BlendMode
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_SetTextureBlendMode
 */
extern DECLSPEC int SDLCALL SDL_GetTextureBlendMode(SDL_Texture * texture,
                                                    SDL_BlendMode *blendMode);

/**
 * Set the scale mode used for texture scale operations.
 *
 * If the scale mode is not supported, the closest supported mode is chosen.
 *
 * \param texture The texture to update.
 * \param scaleMode the SDL_ScaleMode to use for texture scaling.
 * \returns 0 on success, or -1 if the texture is not valid.
 *
 * \sa SDL_GetTextureScaleMode
 */
extern DECLSPEC int SDLCALL SDL_SetTextureScaleMode(SDL_Texture * texture,
                                                    SDL_ScaleMode scaleMode);

/**
 * Get the scale mode used for texture scale operations.
 *
 * \param texture the texture to query.
 * \param scaleMode a pointer filled in with the current scale mode.
 * \return 0 on success, or -1 if the texture is not valid.
 *
 * \sa SDL_SetTextureScaleMode
 */
extern DECLSPEC int SDLCALL SDL_GetTextureScaleMode(SDL_Texture * texture,
                                                    SDL_ScaleMode *scaleMode);

/**
 * Update the given texture rectangle with new pixel data.
 *
 * The pixel data must be in the pixel format of the texture. Use
 * SDL_QueryTexture() to query the pixel format of the texture.
 *
 * This is a fairly slow function, intended for use with static textures that
 * do not change often.
 *
 * If the texture is intended to be updated often, it is preferred to create
 * the texture as streaming and use the locking functions referenced below.
 * While this function will work with streaming textures, for optimization
 * reasons you may not get the pixels back if you lock the texture afterward.
 *
 * \param texture the texture to update
 * \param rect an SDL_Rect structure representing the area to update, or NULL
 *             to update the entire texture
 * \param pixels the raw pixel data in the format of the texture
 * \param pitch the number of bytes in a row of pixel data, including padding
 *              between lines
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_CreateTexture
 * \sa SDL_LockTexture
 * \sa SDL_UnlockTexture
 */
extern DECLSPEC int SDLCALL SDL_UpdateTexture(SDL_Texture * texture,
                                              const SDL_Rect * rect,
                                              const void *pixels, int pitch);

/**
 * Update a rectangle within a planar YV12 or IYUV texture with new pixel
 * data.
 *
 * You can use SDL_UpdateTexture() as long as your pixel data is a contiguous
 * block of Y and U/V planes in the proper order, but this function is
 * available if your pixel data is not contiguous.
 *
 * \param texture the texture to update
 * \param rect a pointer to the rectangle of pixels to update, or NULL to
 *             update the entire texture
 * \param Yplane the raw pixel data for the Y plane
 * \param Ypitch the number of bytes between rows of pixel data for the Y
 *               plane
 * \param Uplane the raw pixel data for the U plane
 * \param Upitch the number of bytes between rows of pixel data for the U
 *               plane
 * \param Vplane the raw pixel data for the V plane
 * \param Vpitch the number of bytes between rows of pixel data for the V
 *               plane
 * \returns 0 on success or -1 if the texture is not valid; call
 *          SDL_GetError() for more information.
 *
 * \since This function is available since SDL 2.0.1.
 *
 * \sa SDL_UpdateTexture
 */
extern DECLSPEC int SDLCALL SDL_UpdateYUVTexture(SDL_Texture * texture,
                                                 const SDL_Rect * rect,
                                                 const Uint8 *Yplane, int Ypitch,
                                                 const Uint8 *Uplane, int Upitch,
                                                 const Uint8 *Vplane, int Vpitch);

/**
 * Update a rectangle within a planar NV12 or NV21 texture with new pixels.
 *
 * You can use SDL_UpdateTexture() as long as your pixel data is a contiguous
 * block of NV12/21 planes in the proper order, but this function is available
 * if your pixel data is not contiguous.
 *
 * \param texture the texture to update
 * \param rect a pointer to the rectangle of pixels to update, or NULL to
 *             update the entire texture.
 * \param Yplane the raw pixel data for the Y plane.
 * \param Ypitch the number of bytes between rows of pixel data for the Y
 *               plane.
 * \param UVplane the raw pixel data for the UV plane.
 * \param UVpitch the number of bytes between rows of pixel data for the UV
 *                plane.
 * \return 0 on success, or -1 if the texture is not valid.
 */
extern DECLSPEC int SDLCALL SDL_UpdateNVTexture(SDL_Texture * texture,
                                                 const SDL_Rect * rect,
                                                 const Uint8 *Yplane, int Ypitch,
                                                 const Uint8 *UVplane, int UVpitch);

/**
 * Lock a portion of the texture for **write-only** pixel access.
 *
 * As an optimization, the pixels made available for editing don't necessarily
 * contain the old texture data. This is a write-only operation, and if you
 * need to keep a copy of the texture data you should do that at the
 * application level.
 *
 * You must use SDL_UnlockTexture() to unlock the pixels and apply any
 * changes.
 *
 * \param texture the texture to lock for access, which was created with
 *                `SDL_TEXTUREACCESS_STREAMING`
 * \param rect an SDL_Rect structure representing the area to lock for access;
 *             NULL to lock the entire texture
 * \param pixels this is filled in with a pointer to the locked pixels,
 *               appropriately offset by the locked area
 * \param pitch this is filled in with the pitch of the locked pixels; the
 *              pitch is the length of one row in bytes
 * \returns 0 on success or a negative error code if the texture is not valid
 *          or was not created with `SDL_TEXTUREACCESS_STREAMING`; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_UnlockTexture
 */
extern DECLSPEC int SDLCALL SDL_LockTexture(SDL_Texture * texture,
                                            const SDL_Rect * rect,
                                            void **pixels, int *pitch);

/**
 * Lock a portion of the texture for **write-only** pixel access, and expose
 * it as a SDL surface.
 *
 * Besides providing an SDL_Surface instead of raw pixel data, this function
 * operates like SDL_LockTexture.
 *
 * As an optimization, the pixels made available for editing don't necessarily
 * contain the old texture data. This is a write-only operation, and if you
 * need to keep a copy of the texture data you should do that at the
 * application level.
 *
 * You must use SDL_UnlockTexture() to unlock the pixels and apply any
 * changes.
 *
 * The returned surface is freed internally after calling SDL_UnlockTexture()
 * or SDL_DestroyTexture(). The caller should not free it.
 *
 * \param texture the texture to lock for access, which was created with
 *                `SDL_TEXTUREACCESS_STREAMING`
 * \param rect a pointer to the rectangle to lock for access. If the rect is
 *             NULL, the entire texture will be locked
 * \param surface this is filled in with an SDL surface representing the
 *                locked area
 * \returns 0 on success, or -1 if the texture is not valid or was not created
 *          with `SDL_TEXTUREACCESS_STREAMING`
 *
 * \sa SDL_LockTexture
 * \sa SDL_UnlockTexture
 */
extern DECLSPEC int SDLCALL SDL_LockTextureToSurface(SDL_Texture *texture,
                                            const SDL_Rect *rect,
                                            SDL_Surface **surface);

/**
 * Unlock a texture, uploading the changes to video memory, if needed.
 *
 * **Warning**: Please note that SDL_LockTexture() is intended to be
 * write-only; it will notguarantee the previous contents of the texture will
 * be provided. You must fully initialize any area of a texture that you lock
 * before unlocking it, as the pixels might otherwise be uninitialized memory.
 *
 * Which is to say: locking and immediately unlocking a texture can result in
 * corrupted textures, depending on the renderer in use.
 *
 * \param texture a texture locked by SDL_LockTexture()
 *
 * \sa SDL_LockTexture
 */
extern DECLSPEC void SDLCALL SDL_UnlockTexture(SDL_Texture * texture);

/**
 * Determine whether a renderer supports the use of render targets.
 *
 * \param renderer the renderer that will be checked
 * \returns SDL_TRUE if supported or SDL_FALSE if not.
 *
 * \since This function is available since SDL 2.0.0.
 *
 * \sa SDL_SetRenderTarget
 */
extern DECLSPEC SDL_bool SDLCALL SDL_RenderTargetSupported(SDL_Renderer *renderer);

/**
 * Set a texture as the current rendering target.
 *
 * Before using this function, you should check the
 * `SDL_RENDERER_TARGETTEXTURE` bit in the flags of SDL_RendererInfo to see if
 * render targets are supported.
 *
 * The default render target is the window for which the renderer was created.
 * To stop rendering to a texture and render to the window again, call this
 * function with a NULL `texture`.
 *
 * \param renderer the rendering context
 * \param texture the targeted texture, which must be created with the
 *                `SDL_TEXTUREACCESS_TARGET` flag, or NULL to render to the
 *                window instead of a texture.
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \since This function is available since SDL 2.0.0.
 *
 * \sa SDL_GetRenderTarget
 */
extern DECLSPEC int SDLCALL SDL_SetRenderTarget(SDL_Renderer *renderer,
                                                SDL_Texture *texture);

/**
 * Get the current render target.
 *
 * The default render target is the window for which the renderer was created,
 * and is reported a NULL here.
 *
 * \param renderer the rendering context
 * \returns the current render target or NULL for the default render target.
 *
 * \since This function is available since SDL 2.0.0.
 *
 * \sa SDL_SetRenderTarget
 */
extern DECLSPEC SDL_Texture * SDLCALL SDL_GetRenderTarget(SDL_Renderer *renderer);

/**
 * Set a device independent resolution for rendering.
 *
 * This function uses the viewport and scaling functionality to allow a fixed
 * logical resolution for rendering, regardless of the actual output
 * resolution. If the actual output resolution doesn't have the same aspect
 * ratio the output rendering will be centered within the output display.
 *
 * If the output display is a window, mouse and touch events in the window
 * will be filtered and scaled so they seem to arrive within the logical
 * resolution.
 *
 * If this function results in scaling or subpixel drawing by the rendering
 * backend, it will be handled using the appropriate quality hints.
 *
 * \param renderer the renderer for which resolution should be set
 * \param w the width of the logical resolution
 * \param h the height of the logical resolution
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \since This function is available since SDL 2.0.0.
 *
 * \sa SDL_RenderGetLogicalSize
 */
extern DECLSPEC int SDLCALL SDL_RenderSetLogicalSize(SDL_Renderer * renderer, int w, int h);

/**
 * Get device independent resolution for rendering.
 *
 * This may return 0 for `w` and `h` if the SDL_Renderer has never had its
 * logical size set by SDL_RenderSetLogicalSize() and never had a render
 * target set.
 *
 * \param renderer a rendering context
 * \param w an int to be filled with the width
 * \param h an int to be filled with the height
 *
 * \since This function is available since SDL 2.0.0.
 *
 * \sa SDL_RenderSetLogicalSize
 */
extern DECLSPEC void SDLCALL SDL_RenderGetLogicalSize(SDL_Renderer * renderer, int *w, int *h);

/**
 * Set whether to force integer scales for resolution-independent rendering.
 *
 * This function restricts the logical viewport to integer values - that is,
 * when a resolution is between two multiples of a logical size, the viewport
 * size is rounded down to the lower multiple.
 *
 * \param renderer the renderer for which integer scaling should be set
 * \param enable enable or disable the integer scaling for rendering
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \since This function is available since SDL 2.0.5.
 *
 * \sa SDL_RenderGetIntegerScale
 * \sa SDL_RenderSetLogicalSize
 */
extern DECLSPEC int SDLCALL SDL_RenderSetIntegerScale(SDL_Renderer * renderer,
                                                      SDL_bool enable);

/**
 * Get whether integer scales are forced for resolution-independent rendering.
 *
 * \param renderer the renderer from which integer scaling should be queried
 * \returns SDL_TRUE if integer scales are forced or SDL_FALSE if not and on
 *          failure; call SDL_GetError() for more information.
 *
 * \since This function is available since SDL 2.0.5.
 *
 * \sa SDL_RenderSetIntegerScale
 */
extern DECLSPEC SDL_bool SDLCALL SDL_RenderGetIntegerScale(SDL_Renderer * renderer);

/**
 * Set the drawing area for rendering on the current target.
 *
 * When the window is resized, the viewport is reset to fill the entire new
 * window size.
 *
 * \param renderer the rendering context
 * \param rect the SDL_Rect structure representing the drawing area, or NULL
 *             to set the viewport to the entire target
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_RenderGetViewport
 */
extern DECLSPEC int SDLCALL SDL_RenderSetViewport(SDL_Renderer * renderer,
                                                  const SDL_Rect * rect);

/**
 * Get the drawing area for the current target.
 *
 * \param renderer the rendering context
 * \param rect an SDL_Rect structure filled in with the current drawing area
 *
 * \sa SDL_RenderSetViewport
 */
extern DECLSPEC void SDLCALL SDL_RenderGetViewport(SDL_Renderer * renderer,
                                                   SDL_Rect * rect);

/**
 * Set the clip rectangle for rendering on the specified target.
 *
 * \param renderer the rendering context for which clip rectangle should be
 *                 set
 * \param rect an SDL_Rect structure representing the clip area, relative to
 *             the viewport, or NULL to disable clipping
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_RenderGetClipRect
 * \sa SDL_RenderIsClipEnabled
 */
extern DECLSPEC int SDLCALL SDL_RenderSetClipRect(SDL_Renderer * renderer,
                                                  const SDL_Rect * rect);

/**
 * Get the clip rectangle for the current target.
 *
 * \param renderer the rendering context from which clip rectangle should be
 *                 queried
 * \param rect an SDL_Rect structure filled in with the current clipping area
 *             or an empty rectangle if clipping is disabled
 *
 * \sa SDL_RenderIsClipEnabled
 * \sa SDL_RenderSetClipRect
 */
extern DECLSPEC void SDLCALL SDL_RenderGetClipRect(SDL_Renderer * renderer,
                                                   SDL_Rect * rect);

/**
 * Get whether clipping is enabled on the given renderer.
 *
 * \param renderer the renderer from which clip state should be queried
 * \returns SDL_TRUE if clipping is enabled or SDL_FALSE if not; call
 *          SDL_GetError() for more information.
 *
 * \since This function is available since SDL 2.0.4.
 *
 * \sa SDL_RenderGetClipRect
 * \sa SDL_RenderSetClipRect
 */
extern DECLSPEC SDL_bool SDLCALL SDL_RenderIsClipEnabled(SDL_Renderer * renderer);


/**
 * Set the drawing scale for rendering on the current target.
 *
 * The drawing coordinates are scaled by the x/y scaling factors before they
 * are used by the renderer. This allows resolution independent drawing with a
 * single coordinate system.
 *
 * If this results in scaling or subpixel drawing by the rendering backend, it
 * will be handled using the appropriate quality hints. For best results use
 * integer scaling factors.
 *
 * \param renderer a rendering context
 * \param scaleX the horizontal scaling factor
 * \param scaleY the vertical scaling factor
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \since This function is available since SDL 2.0.0.
 *
 * \sa SDL_RenderGetScale
 * \sa SDL_RenderSetLogicalSize
 */
extern DECLSPEC int SDLCALL SDL_RenderSetScale(SDL_Renderer * renderer,
                                               float scaleX, float scaleY);

/**
 * Get the drawing scale for the current target.
 *
 * \param renderer the renderer from which drawing scale should be queried
 * \param scaleX a pointer filled in with the horizontal scaling factor
 * \param scaleY a pointer filled in with the vertical scaling factor
 *
 * \since This function is available since SDL 2.0.0.
 *
 * \sa SDL_RenderSetScale
 */
extern DECLSPEC void SDLCALL SDL_RenderGetScale(SDL_Renderer * renderer,
                                               float *scaleX, float *scaleY);

/**
 * Set the color used for drawing operations (Rect, Line and Clear).
 *
 * Set the color for drawing or filling rectangles, lines, and points, and for
 * SDL_RenderClear().
 *
 * \param renderer the rendering context
 * \param r the red value used to draw on the rendering target
 * \param g the green value used to draw on the rendering target
 * \param b the blue value used to draw on the rendering target
 * \param a the alpha value used to draw on the rendering target; usually
 *          `SDL_ALPHA_OPAQUE` (255). Use SDL_SetRenderDrawBlendMode to
 *          specify how the alpha channel is used
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_GetRenderDrawColor
 * \sa SDL_RenderClear
 * \sa SDL_RenderDrawLine
 * \sa SDL_RenderDrawLines
 * \sa SDL_RenderDrawPoint
 * \sa SDL_RenderDrawPoints
 * \sa SDL_RenderDrawRect
 * \sa SDL_RenderDrawRects
 * \sa SDL_RenderFillRect
 * \sa SDL_RenderFillRects
 */
extern DECLSPEC int SDLCALL SDL_SetRenderDrawColor(SDL_Renderer * renderer,
                                           Uint8 r, Uint8 g, Uint8 b,
                                           Uint8 a);

/**
 * Get the color used for drawing operations (Rect, Line and Clear).
 *
 * \param renderer the rendering context
 * \param r a pointer filled in with the red value used to draw on the
 *          rendering target
 * \param g a pointer filled in with the green value used to draw on the
 *          rendering target
 * \param b a pointer filled in with the blue value used to draw on the
 *          rendering target
 * \param a a pointer filled in with the alpha value used to draw on the
 *          rendering target; usually `SDL_ALPHA_OPAQUE` (255)
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_SetRenderDrawColor
 */
extern DECLSPEC int SDLCALL SDL_GetRenderDrawColor(SDL_Renderer * renderer,
                                           Uint8 * r, Uint8 * g, Uint8 * b,
                                           Uint8 * a);

/**
 * Set the blend mode used for drawing operations (Fill and Line).
 *
 * If the blend mode is not supported, the closest supported mode is chosen.
 *
 * \param renderer the rendering context
 * \param blendMode the SDL_BlendMode to use for blending
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_GetRenderDrawBlendMode
 * \sa SDL_RenderDrawLine
 * \sa SDL_RenderDrawLines
 * \sa SDL_RenderDrawPoint
 * \sa SDL_RenderDrawPoints
 * \sa SDL_RenderDrawRect
 * \sa SDL_RenderDrawRects
 * \sa SDL_RenderFillRect
 * \sa SDL_RenderFillRects
 */
extern DECLSPEC int SDLCALL SDL_SetRenderDrawBlendMode(SDL_Renderer * renderer,
                                                       SDL_BlendMode blendMode);

/**
 * Get the blend mode used for drawing operations.
 *
 * \param renderer the rendering context
 * \param blendMode a pointer filled in with the current SDL_BlendMode
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_SetRenderDrawBlendMode
 */
extern DECLSPEC int SDLCALL SDL_GetRenderDrawBlendMode(SDL_Renderer * renderer,
                                                       SDL_BlendMode *blendMode);

/**
 * Clear the current rendering target with the drawing color.
 *
 * This function clears the entire rendering target, ignoring the viewport and
 * the clip rectangle.
 *
 * \param renderer the rendering context
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \since This function is available since SDL 2.0.0.
 *
 * \sa SDL_SetRenderDrawColor
 */
extern DECLSPEC int SDLCALL SDL_RenderClear(SDL_Renderer * renderer);

/**
 * Draw a point on the current rendering target.
 *
 * SDL_RenderDrawPoint() draws a single point. If you want to draw multiple,
 * use SDL_RenderDrawPoints() instead.
 *
 * \param renderer the rendering context
 * \param x the x coordinate of the point
 * \param y the y coordinate of the point
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_RenderDrawLine
 * \sa SDL_RenderDrawLines
 * \sa SDL_RenderDrawPoints
 * \sa SDL_RenderDrawRect
 * \sa SDL_RenderDrawRects
 * \sa SDL_RenderFillRect
 * \sa SDL_RenderFillRects
 * \sa SDL_RenderPresent
 * \sa SDL_SetRenderDrawBlendMode
 * \sa SDL_SetRenderDrawColor
 */
extern DECLSPEC int SDLCALL SDL_RenderDrawPoint(SDL_Renderer * renderer,
                                                int x, int y);

/**
 * Draw multiple points on the current rendering target.
 *
 * \param renderer the rendering context
 * \param points an array of SDL_Point structures that represent the points to
 *               draw
 * \param count the number of points to draw
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_RenderDrawLine
 * \sa SDL_RenderDrawLines
 * \sa SDL_RenderDrawPoint
 * \sa SDL_RenderDrawRect
 * \sa SDL_RenderDrawRects
 * \sa SDL_RenderFillRect
 * \sa SDL_RenderFillRects
 * \sa SDL_RenderPresent
 * \sa SDL_SetRenderDrawBlendMode
 * \sa SDL_SetRenderDrawColor
 */
extern DECLSPEC int SDLCALL SDL_RenderDrawPoints(SDL_Renderer * renderer,
                                                 const SDL_Point * points,
                                                 int count);

/**
 * Draw a line on the current rendering target.
 *
 * SDL_RenderDrawLine() draws the line to include both end points. If you want
 * to draw multiple, connecting lines use SDL_RenderDrawLines() instead.
 *
 * \param renderer the rendering context
 * \param x1 the x coordinate of the start point
 * \param y1 the y coordinate of the start point
 * \param x2 the x coordinate of the end point
 * \param y2 the y coordinate of the end point
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \since This function is available since SDL 2.0.0.
 *
 * \sa SDL_RenderDrawLines
 * \sa SDL_RenderDrawPoint
 * \sa SDL_RenderDrawPoints
 * \sa SDL_RenderDrawRect
 * \sa SDL_RenderDrawRects
 * \sa SDL_RenderFillRect
 * \sa SDL_RenderFillRects
 * \sa SDL_RenderPresent
 * \sa SDL_SetRenderDrawBlendMode
 * \sa SDL_SetRenderDrawColor
 */
extern DECLSPEC int SDLCALL SDL_RenderDrawLine(SDL_Renderer * renderer,
                                               int x1, int y1, int x2, int y2);

/**
 * Draw a series of connected lines on the current rendering target.
 *
 * \param renderer the rendering context
 * \param points an array of SDL_Point structures representing points along
 *               the lines
 * \param count the number of points, drawing count-1 lines
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \since This function is available since SDL 2.0.0.
 *
 * \sa SDL_RenderDrawLine
 * \sa SDL_RenderDrawPoint
 * \sa SDL_RenderDrawPoints
 * \sa SDL_RenderDrawRect
 * \sa SDL_RenderDrawRects
 * \sa SDL_RenderFillRect
 * \sa SDL_RenderFillRects
 * \sa SDL_RenderPresent
 * \sa SDL_SetRenderDrawBlendMode
 * \sa SDL_SetRenderDrawColor
 */
extern DECLSPEC int SDLCALL SDL_RenderDrawLines(SDL_Renderer * renderer,
                                                const SDL_Point * points,
                                                int count);

/**
 * Draw a rectangle on the current rendering target.
 *
 * \param renderer the rendering context
 * \param rect an SDL_Rect structure representing the rectangle to draw, or
 *             NULL to outline the entire rendering target
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_RenderDrawLine
 * \sa SDL_RenderDrawLines
 * \sa SDL_RenderDrawPoint
 * \sa SDL_RenderDrawPoints
 * \sa SDL_RenderDrawRects
 * \sa SDL_RenderFillRect
 * \sa SDL_RenderFillRects
 * \sa SDL_RenderPresent
 * \sa SDL_SetRenderDrawBlendMode
 * \sa SDL_SetRenderDrawColor
 */
extern DECLSPEC int SDLCALL SDL_RenderDrawRect(SDL_Renderer * renderer,
                                               const SDL_Rect * rect);

/**
 * Draw some number of rectangles on the current rendering target.
 *
 * \param renderer the rendering context
 * \param rects an array of SDL_Rect structures representing the rectangles to
 *              be drawn
 * \param count the number of rectangles
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_RenderDrawLine
 * \sa SDL_RenderDrawLines
 * \sa SDL_RenderDrawPoint
 * \sa SDL_RenderDrawPoints
 * \sa SDL_RenderDrawRect
 * \sa SDL_RenderFillRect
 * \sa SDL_RenderFillRects
 * \sa SDL_RenderPresent
 * \sa SDL_SetRenderDrawBlendMode
 * \sa SDL_SetRenderDrawColor
 */
extern DECLSPEC int SDLCALL SDL_RenderDrawRects(SDL_Renderer * renderer,
                                                const SDL_Rect * rects,
                                                int count);

/**
 * Fill a rectangle on the current rendering target with the drawing color.
 *
 * The current drawing color is set by SDL_SetRenderDrawColor(), and the
 * color's alpha value is ignored unless blending is enabled with the
 * appropriate call to SDL_SetRenderDrawBlendMode().
 *
 * \param renderer the rendering context
 * \param rect the SDL_Rect structure representing the rectangle to fill, or
 *             NULL for the entire rendering target
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_RenderDrawLine
 * \sa SDL_RenderDrawLines
 * \sa SDL_RenderDrawPoint
 * \sa SDL_RenderDrawPoints
 * \sa SDL_RenderDrawRect
 * \sa SDL_RenderDrawRects
 * \sa SDL_RenderFillRects
 * \sa SDL_RenderPresent
 * \sa SDL_SetRenderDrawBlendMode
 * \sa SDL_SetRenderDrawColor
 */
extern DECLSPEC int SDLCALL SDL_RenderFillRect(SDL_Renderer * renderer,
                                               const SDL_Rect * rect);

/**
 * Fill some number of rectangles on the current rendering target with the
 * drawing color.
 *
 * \param renderer the rendering context
 * \param rects an array of SDL_Rect structures representing the rectangles to
 *              be filled
 * \param count the number of rectangles
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_RenderDrawLine
 * \sa SDL_RenderDrawLines
 * \sa SDL_RenderDrawPoint
 * \sa SDL_RenderDrawPoints
 * \sa SDL_RenderDrawRect
 * \sa SDL_RenderDrawRects
 * \sa SDL_RenderFillRect
 * \sa SDL_RenderPresent
 */
extern DECLSPEC int SDLCALL SDL_RenderFillRects(SDL_Renderer * renderer,
                                                const SDL_Rect * rects,
                                                int count);

/**
 * Copy a portion of the texture to the current rendering target.
 *
 * The texture is blended with the destination based on its blend mode set
 * with SDL_SetTextureBlendMode().
 *
 * The texture color is affected based on its color modulation set by
 * SDL_SetTextureColorMod().
 *
 * The texture alpha is affected based on its alpha modulation set by
 * SDL_SetTextureAlphaMod().
 *
 * \param renderer the rendering context
 * \param texture the source texture
 * \param srcrect the source SDL_Rect structure or NULL for the entire texture
 * \param dstrect the destination SDL_Rect structure or NULL for the entire
 *                rendering target; the texture will be stretched to fill the
 *                given rectangle
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_RenderCopyEx
 * \sa SDL_SetTextureAlphaMod
 * \sa SDL_SetTextureBlendMode
 * \sa SDL_SetTextureColorMod
 */
extern DECLSPEC int SDLCALL SDL_RenderCopy(SDL_Renderer * renderer,
                                           SDL_Texture * texture,
                                           const SDL_Rect * srcrect,
                                           const SDL_Rect * dstrect);

/**
 * Copy a portion of the texture to the current rendering, with optional
 * rotation and flipping.
 *
 * Copy a portion of the texture to the current rendering target, optionally
 * rotating it by angle around the given center and also flipping it
 * top-bottom and/or left-right.
 *
 * The texture is blended with the destination based on its blend mode set
 * with SDL_SetTextureBlendMode().
 *
 * The texture color is affected based on its color modulation set by
 * SDL_SetTextureColorMod().
 *
 * The texture alpha is affected based on its alpha modulation set by
 * SDL_SetTextureAlphaMod().
 *
 * \param renderer the rendering context
 * \param texture the source texture
 * \param srcrect the source SDL_Rect structure or NULL for the entire texture
 * \param dstrect the destination SDL_Rect structure or NULL for the entire
 *                rendering target
 * \param angle an angle in degrees that indicates the rotation that will be
 *              applied to dstrect, rotating it in a clockwise direction
 * \param center a pointer to a point indicating the point around which
 *               dstrect will be rotated (if NULL, rotation will be done
 *               around `dstrect.w / 2`, `dstrect.h / 2`)
 * \param flip a SDL_RendererFlip value stating which flipping actions should
 *             be performed on the texture
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \sa SDL_RenderCopy
 * \sa SDL_SetTextureAlphaMod
 * \sa SDL_SetTextureBlendMode
 * \sa SDL_SetTextureColorMod
 */
extern DECLSPEC int SDLCALL SDL_RenderCopyEx(SDL_Renderer * renderer,
                                           SDL_Texture * texture,
                                           const SDL_Rect * srcrect,
                                           const SDL_Rect * dstrect,
                                           const double angle,
                                           const SDL_Point *center,
                                           const SDL_RendererFlip flip);


/**
 * Draw a point on the current rendering target at subpixel precision.
 *
 * \param renderer The renderer which should draw a point.
 * \param x The x coordinate of the point.
 * \param y The y coordinate of the point.
 * \return 0 on success, or -1 on error
 */
extern DECLSPEC int SDLCALL SDL_RenderDrawPointF(SDL_Renderer * renderer,
                                                 float x, float y);

/**
 * Draw multiple points on the current rendering target at subpixel precision.
 *
 * \param renderer The renderer which should draw multiple points.
 * \param points The points to draw
 * \param count The number of points to draw
 * \return 0 on success, or -1 on error
 */
extern DECLSPEC int SDLCALL SDL_RenderDrawPointsF(SDL_Renderer * renderer,
                                                  const SDL_FPoint * points,
                                                  int count);

/**
 * Draw a line on the current rendering target at subpixel precision.
 *
 * \param renderer The renderer which should draw a line.
 * \param x1 The x coordinate of the start point.
 * \param y1 The y coordinate of the start point.
 * \param x2 The x coordinate of the end point.
 * \param y2 The y coordinate of the end point.
 * \return 0 on success, or -1 on error
 */
extern DECLSPEC int SDLCALL SDL_RenderDrawLineF(SDL_Renderer * renderer,
                                                float x1, float y1, float x2, float y2);

/**
 * Draw a series of connected lines on the current rendering target at
 * subpixel precision.
 *
 * \param renderer The renderer which should draw multiple lines.
 * \param points The points along the lines
 * \param count The number of points, drawing count-1 lines
 * \return 0 on success, or -1 on error
 */
extern DECLSPEC int SDLCALL SDL_RenderDrawLinesF(SDL_Renderer * renderer,
                                                 const SDL_FPoint * points,
                                                 int count);

/**
 * Draw a rectangle on the current rendering target at subpixel precision.
 *
 * \param renderer The renderer which should draw a rectangle.
 * \param rect A pointer to the destination rectangle, or NULL to outline the
 *             entire rendering target.
 * \return 0 on success, or -1 on error
 */
extern DECLSPEC int SDLCALL SDL_RenderDrawRectF(SDL_Renderer * renderer,
                                                const SDL_FRect * rect);

/**
 * Draw some number of rectangles on the current rendering target at subpixel
 * precision.
 *
 * \param renderer The renderer which should draw multiple rectangles.
 * \param rects A pointer to an array of destination rectangles.
 * \param count The number of rectangles.
 * \return 0 on success, or -1 on error
 */
extern DECLSPEC int SDLCALL SDL_RenderDrawRectsF(SDL_Renderer * renderer,
                                                 const SDL_FRect * rects,
                                                 int count);

/**
 * Fill a rectangle on the current rendering target with the drawing color at
 * subpixel precision.
 *
 * \param renderer The renderer which should fill a rectangle.
 * \param rect A pointer to the destination rectangle, or NULL for the entire
 *             rendering target.
 * \return 0 on success, or -1 on error
 */
extern DECLSPEC int SDLCALL SDL_RenderFillRectF(SDL_Renderer * renderer,
                                                const SDL_FRect * rect);

/**
 * Fill some number of rectangles on the current rendering target with the
 * drawing color at subpixel precision.
 *
 * \param renderer The renderer which should fill multiple rectangles.
 * \param rects A pointer to an array of destination rectangles.
 * \param count The number of rectangles.
 * \return 0 on success, or -1 on error
 */
extern DECLSPEC int SDLCALL SDL_RenderFillRectsF(SDL_Renderer * renderer,
                                                 const SDL_FRect * rects,
                                                 int count);

/**
 * Copy a portion of the texture to the current rendering target at subpixel
 * precision.
 *
 * \param renderer The renderer which should copy parts of a texture.
 * \param texture The source texture.
 * \param srcrect A pointer to the source rectangle, or NULL for the entire
 *                texture.
 * \param dstrect A pointer to the destination rectangle, or NULL for the
 *                entire rendering target.
 * \return 0 on success, or -1 on error
 */
extern DECLSPEC int SDLCALL SDL_RenderCopyF(SDL_Renderer * renderer,
                                            SDL_Texture * texture,
                                            const SDL_Rect * srcrect,
                                            const SDL_FRect * dstrect);

/**
 * Copy a portion of the source texture to the current rendering target, with
 * rotation and flipping, at subpixel precision.
 *
 * \param renderer The renderer which should copy parts of a texture.
 * \param texture The source texture.
 * \param srcrect A pointer to the source rectangle, or NULL for the entire
 *                texture.
 * \param dstrect A pointer to the destination rectangle, or NULL for the
 *                entire rendering target.
 * \param angle An angle in degrees that indicates the rotation that will be
 *              applied to dstrect, rotating it in a clockwise direction
 * \param center A pointer to a point indicating the point around which
 *               dstrect will be rotated (if NULL, rotation will be done
 *               around dstrect.w/2, dstrect.h/2).
 * \param flip An SDL_RendererFlip value stating which flipping actions should
 *             be performed on the texture
 * \return 0 on success, or -1 on error
 */
extern DECLSPEC int SDLCALL SDL_RenderCopyExF(SDL_Renderer * renderer,
                                            SDL_Texture * texture,
                                            const SDL_Rect * srcrect,
                                            const SDL_FRect * dstrect,
                                            const double angle,
                                            const SDL_FPoint *center,
                                            const SDL_RendererFlip flip);

/**
 * Read pixels from the current rendering target to an array of pixels.
 *
 * **WARNING**: This is a very slow operation, and should not be used
 * frequently.
 *
 * `pitch` specifies the number of bytes between rows in the destination
 * `pixels data. This allows you to write to a subrectangle or have padded
 * rows in the destination. Generally, `pitch` should equal the number of
 * pixels per row in the `pixels` data times the number of bytes per pixel,
 * but it might contain additional padding (for example, 24bit RGB Windows
 * Bitmap data pads all rows to multiples of 4 bytes).
 *
 * \param renderer the rendering context
 * \param rect an SDL_Rect structure representing the area to read, or NULL
 *             for the entire render target
 * \param format an SDL_PixelFormatEnum value of the desired format of the
 *               pixel data, or 0 to use the format of the rendering target
 * \param pixels a pointer to the pixel data to copy into
 * \param pitch the pitch of the `pixels` parameter
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 */
extern DECLSPEC int SDLCALL SDL_RenderReadPixels(SDL_Renderer * renderer,
                                                 const SDL_Rect * rect,
                                                 Uint32 format,
                                                 void *pixels, int pitch);

/**
 * Update the screen with any rendering performed since the previous call.
 *
 * SDL's rendering functions operate on a backbuffer; that is, calling a
 * rendering function such as SDL_RenderDrawLine() does not directly put a
 * line on the screen, but rather updates the backbuffer. As such, you compose
 * your entire scene and *present* the composed backbuffer to the screen as a
 * complete picture.
 *
 * Therefore, when using SDL's rendering API, one does all drawing intended
 * for the frame, and then calls this function once per frame to present the
 * final drawing to the user.
 *
 * The backbuffer should be considered invalidated after each present; do not
 * assume that previous contents will exist between frames. You are strongly
 * encouraged to call SDL_RenderClear() to initialize the backbuffer before
 * starting each new frame's drawing, even if you plan to overwrite every
 * pixel.
 *
 * \param renderer the rendering context
 *
 * \sa SDL_RenderClear
 * \sa SDL_RenderDrawLine
 * \sa SDL_RenderDrawLines
 * \sa SDL_RenderDrawPoint
 * \sa SDL_RenderDrawPoints
 * \sa SDL_RenderDrawRect
 * \sa SDL_RenderDrawRects
 * \sa SDL_RenderFillRect
 * \sa SDL_RenderFillRects
 * \sa SDL_SetRenderDrawBlendMode
 * \sa SDL_SetRenderDrawColor
 */
extern DECLSPEC void SDLCALL SDL_RenderPresent(SDL_Renderer * renderer);

/**
 * Destroy the specified texture.
 *
 * Passing NULL or an otherwise invalid texture will set the SDL error message
 * to "Invalid texture".
 *
 * \param texture the texture to destroy
 *
 * \sa SDL_CreateTexture
 * \sa SDL_CreateTextureFromSurface
 */
extern DECLSPEC void SDLCALL SDL_DestroyTexture(SDL_Texture * texture);

/**
 * Destroy the rendering context for a window and free associated textures.
 *
 * \param renderer the rendering context
 *
 * \sa SDL_CreateRenderer
 */
extern DECLSPEC void SDLCALL SDL_DestroyRenderer(SDL_Renderer * renderer);

/**
 * Force the rendering context to flush any pending commands to the underlying
 * rendering API.
 *
 * You do not need to (and in fact, shouldn't) call this function unless you
 * are planning to call into OpenGL/Direct3D/Metal/whatever directly in
 * addition to using an SDL_Renderer.
 *
 * This is for a very-specific case: if you are using SDL's render API, you
 * asked for a specific renderer backend (OpenGL, Direct3D, etc), you set
 * SDL_HINT_RENDER_BATCHING to "1", and you plan to make OpenGL/D3D/whatever
 * calls in addition to SDL render API calls. If all of this applies, you
 * should call SDL_RenderFlush() between calls to SDL's render API and the
 * low-level API you're using in cooperation.
 *
 * In all other cases, you can ignore this function. This is only here to get
 * maximum performance out of a specific situation. In all other cases, SDL
 * will do the right thing, perhaps at a performance loss.
 *
 * This function is first available in SDL 2.0.10, and is not needed in 2.0.9
 * and earlier, as earlier versions did not queue rendering commands at all,
 * instead flushing them to the OS immediately.
 *
 * \param renderer the rendering context
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \since This function is available since SDL 2.0.10.
 */
extern DECLSPEC int SDLCALL SDL_RenderFlush(SDL_Renderer * renderer);


/**
 * Bind an OpenGL/ES/ES2 texture to the current context.
 *
 * This is for use with OpenGL instructions when rendering OpenGL primitives
 * directly.
 *
 * If not NULL, `texw` and `texh` will be filled with the width and height
 * values suitable for the provided texture. In most cases, both will be 1.0,
 * however, on systems that support the GL_ARB_texture_rectangle extension,
 * these values will actually be the pixel width and height used to create the
 * texture, so this factor needs to be taken into account when providing
 * texture coordinates to OpenGL.
 *
 * You need a renderer to create an SDL_Texture, therefore you can only use
 * this function with an implicit OpenGL context from SDL_CreateRenderer(),
 * not with your own OpenGL context. If you need control over your OpenGL
 * context, you need to write your own texture-loading methods.
 *
 * Also note that SDL may upload RGB textures as BGR (or vice-versa), and
 * re-order the color channels in the shaders phase, so the uploaded texture
 * may have swapped color channels.
 *
 * \param texture the texture to bind to the current OpenGL/ES/ES2 context
 * \param texw a pointer to a float value which will be filled with the
 *             texture width or NULL if you don't need that value
 * \param texh a pointer to a float value which will be filled with the
 *             texture height or NULL if you don't need that value
 * \returns 0 on success, or -1 if the operation is not supported; call
 *          SDL_GetError() for more information.
 *
 * \since This function is available since SDL 2.0.0.
 *
 * \sa SDL_GL_MakeCurrent
 * \sa SDL_GL_UnbindTexture
 */
extern DECLSPEC int SDLCALL SDL_GL_BindTexture(SDL_Texture *texture, float *texw, float *texh);

/**
 * Unbind an OpenGL/ES/ES2 texture from the current context.
 *
 * See SDL_GL_BindTexture() for examples on how to use these functions
 *
 * \param texture the texture to unbind from the current OpenGL/ES/ES2 context
 * \returns 0 on success, or -1 if the operation is not supported
 *
 * \sa SDL_GL_BindTexture
 * \sa SDL_GL_MakeCurrent
 */
extern DECLSPEC int SDLCALL SDL_GL_UnbindTexture(SDL_Texture *texture);

/**
 * Get the CAMetalLayer associated with the given Metal renderer.
 *
 * This function returns `void *`, so SDL doesn't have to include Metal's
 * headers, but it can be safely cast to a `CAMetalLayer *`.
 *
 * \param renderer The renderer to query
 * \returns a `CAMetalLayer *` on success, or NULL if the renderer isn't a
 *          Metal renderer
 *
 * \sa SDL_RenderGetMetalCommandEncoder
 */
extern DECLSPEC void *SDLCALL SDL_RenderGetMetalLayer(SDL_Renderer * renderer);

/**
 * Get the Metal command encoder for the current frame
 *
 * This function returns `void *`, so SDL doesn't have to include Metal's
 * headers, but it can be safely cast to an `id<MTLRenderCommandEncoder>`.
 *
 * \param renderer The renderer to query
 * \returns an `id<MTLRenderCommandEncoder>` on success, or NULL if the
 *          renderer isn't a Metal renderer.
 *
 * \sa SDL_RenderGetMetalLayer
 */
extern DECLSPEC void *SDLCALL SDL_RenderGetMetalCommandEncoder(SDL_Renderer * renderer);

/* Ends C function definitions when using C++ */
#ifdef __cplusplus
}
#endif
#include "close_code.h"

#endif /* SDL_render_h_ */

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