SDL 3.0
SDL_render.h File Reference
#include <SDL3/SDL_stdinc.h>
#include <SDL3/SDL_events.h>
#include <SDL3/SDL_rect.h>
#include <SDL3/SDL_video.h>
#include <SDL3/SDL_begin_code.h>
#include <SDL3/SDL_close_code.h>
+ Include dependency graph for SDL_render.h:
+ This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Data Structures

struct  SDL_RendererInfo
 
struct  SDL_Vertex
 

Typedefs

typedef struct SDL_Renderer SDL_Renderer
 
typedef struct SDL_Texture SDL_Texture
 

Enumerations

enum  SDL_RendererFlags {
  SDL_RENDERER_SOFTWARE = 0x00000001 ,
  SDL_RENDERER_ACCELERATED = 0x00000002 ,
  SDL_RENDERER_PRESENTVSYNC = 0x00000004
}
 
enum  SDL_ScaleMode {
  SDL_SCALEMODE_NEAREST ,
  SDL_SCALEMODE_LINEAR ,
  SDL_SCALEMODE_BEST
}
 
enum  SDL_TextureAccess {
  SDL_TEXTUREACCESS_STATIC ,
  SDL_TEXTUREACCESS_STREAMING ,
  SDL_TEXTUREACCESS_TARGET
}
 
enum  SDL_TextureModulate {
  SDL_TEXTUREMODULATE_NONE = 0x00000000 ,
  SDL_TEXTUREMODULATE_COLOR = 0x00000001 ,
  SDL_TEXTUREMODULATE_ALPHA = 0x00000002
}
 
enum  SDL_RendererFlip {
  SDL_FLIP_NONE = 0x00000000 ,
  SDL_FLIP_HORIZONTAL = 0x00000001 ,
  SDL_FLIP_VERTICAL = 0x00000002
}
 
enum  SDL_RendererLogicalPresentation {
  SDL_LOGICAL_PRESENTATION_DISABLED ,
  SDL_LOGICAL_PRESENTATION_MATCH ,
  SDL_LOGICAL_PRESENTATION_STRETCH ,
  SDL_LOGICAL_PRESENTATION_LETTERBOX ,
  SDL_LOGICAL_PRESENTATION_OVERSCAN ,
  SDL_LOGICAL_PRESENTATION_INTEGER_SCALE
}
 

Functions

int SDL_GetNumRenderDrivers (void)
 
const char * SDL_GetRenderDriver (int index)
 
int SDL_CreateWindowAndRenderer (int width, int height, Uint32 window_flags, SDL_Window **window, SDL_Renderer **renderer)
 
SDL_RendererSDL_CreateRenderer (SDL_Window *window, const char *name, Uint32 flags)
 
SDL_RendererSDL_CreateSoftwareRenderer (SDL_Surface *surface)
 
SDL_RendererSDL_GetRenderer (SDL_Window *window)
 
SDL_WindowSDL_GetRenderWindow (SDL_Renderer *renderer)
 
int SDL_GetRendererInfo (SDL_Renderer *renderer, SDL_RendererInfo *info)
 
int SDL_GetRenderWindowSize (SDL_Renderer *renderer, int *w, int *h)
 
int SDL_GetRenderOutputSize (SDL_Renderer *renderer, int *w, int *h)
 
int SDL_GetCurrentRenderOutputSize (SDL_Renderer *renderer, int *w, int *h)
 
SDL_TextureSDL_CreateTexture (SDL_Renderer *renderer, Uint32 format, int access, int w, int h)
 
SDL_TextureSDL_CreateTextureFromSurface (SDL_Renderer *renderer, SDL_Surface *surface)
 
int SDL_QueryTexture (SDL_Texture *texture, Uint32 *format, int *access, int *w, int *h)
 
int SDL_SetTextureColorMod (SDL_Texture *texture, Uint8 r, Uint8 g, Uint8 b)
 
int SDL_GetTextureColorMod (SDL_Texture *texture, Uint8 *r, Uint8 *g, Uint8 *b)
 
int SDL_SetTextureAlphaMod (SDL_Texture *texture, Uint8 alpha)
 
int SDL_GetTextureAlphaMod (SDL_Texture *texture, Uint8 *alpha)
 
int SDL_SetTextureBlendMode (SDL_Texture *texture, SDL_BlendMode blendMode)
 
int SDL_GetTextureBlendMode (SDL_Texture *texture, SDL_BlendMode *blendMode)
 
int SDL_SetTextureScaleMode (SDL_Texture *texture, SDL_ScaleMode scaleMode)
 
int SDL_GetTextureScaleMode (SDL_Texture *texture, SDL_ScaleMode *scaleMode)
 
int SDL_SetTextureUserData (SDL_Texture *texture, void *userdata)
 
voidSDL_GetTextureUserData (SDL_Texture *texture)
 
int SDL_UpdateTexture (SDL_Texture *texture, const SDL_Rect *rect, const void *pixels, int pitch)
 
int SDL_UpdateYUVTexture (SDL_Texture *texture, const SDL_Rect *rect, const Uint8 *Yplane, int Ypitch, const Uint8 *Uplane, int Upitch, const Uint8 *Vplane, int Vpitch)
 
int SDL_UpdateNVTexture (SDL_Texture *texture, const SDL_Rect *rect, const Uint8 *Yplane, int Ypitch, const Uint8 *UVplane, int UVpitch)
 
int SDL_LockTexture (SDL_Texture *texture, const SDL_Rect *rect, void **pixels, int *pitch)
 
int SDL_LockTextureToSurface (SDL_Texture *texture, const SDL_Rect *rect, SDL_Surface **surface)
 
void SDL_UnlockTexture (SDL_Texture *texture)
 
int SDL_SetRenderTarget (SDL_Renderer *renderer, SDL_Texture *texture)
 
SDL_TextureSDL_GetRenderTarget (SDL_Renderer *renderer)
 
int SDL_SetRenderLogicalPresentation (SDL_Renderer *renderer, int w, int h, SDL_RendererLogicalPresentation mode, SDL_ScaleMode scale_mode)
 
int SDL_GetRenderLogicalPresentation (SDL_Renderer *renderer, int *w, int *h, SDL_RendererLogicalPresentation *mode, SDL_ScaleMode *scale_mode)
 
int SDL_RenderCoordinatesFromWindow (SDL_Renderer *renderer, float window_x, float window_y, float *x, float *y)
 
int SDL_RenderCoordinatesToWindow (SDL_Renderer *renderer, float x, float y, float *window_x, float *window_y)
 
int SDL_ConvertEventToRenderCoordinates (SDL_Renderer *renderer, SDL_Event *event)
 
int SDL_SetRenderViewport (SDL_Renderer *renderer, const SDL_Rect *rect)
 
int SDL_GetRenderViewport (SDL_Renderer *renderer, SDL_Rect *rect)
 
int SDL_SetRenderClipRect (SDL_Renderer *renderer, const SDL_Rect *rect)
 
int SDL_GetRenderClipRect (SDL_Renderer *renderer, SDL_Rect *rect)
 
SDL_bool SDL_RenderClipEnabled (SDL_Renderer *renderer)
 
int SDL_SetRenderScale (SDL_Renderer *renderer, float scaleX, float scaleY)
 
int SDL_GetRenderScale (SDL_Renderer *renderer, float *scaleX, float *scaleY)
 
int SDL_SetRenderDrawColor (SDL_Renderer *renderer, Uint8 r, Uint8 g, Uint8 b, Uint8 a)
 
int SDL_GetRenderDrawColor (SDL_Renderer *renderer, Uint8 *r, Uint8 *g, Uint8 *b, Uint8 *a)
 
int SDL_SetRenderDrawBlendMode (SDL_Renderer *renderer, SDL_BlendMode blendMode)
 
int SDL_GetRenderDrawBlendMode (SDL_Renderer *renderer, SDL_BlendMode *blendMode)
 
int SDL_RenderClear (SDL_Renderer *renderer)
 
int SDL_RenderPoint (SDL_Renderer *renderer, float x, float y)
 
int SDL_RenderPoints (SDL_Renderer *renderer, const SDL_FPoint *points, int count)
 
int SDL_RenderLine (SDL_Renderer *renderer, float x1, float y1, float x2, float y2)
 
int SDL_RenderLines (SDL_Renderer *renderer, const SDL_FPoint *points, int count)
 
int SDL_RenderRect (SDL_Renderer *renderer, const SDL_FRect *rect)
 
int SDL_RenderRects (SDL_Renderer *renderer, const SDL_FRect *rects, int count)
 
int SDL_RenderFillRect (SDL_Renderer *renderer, const SDL_FRect *rect)
 
int SDL_RenderFillRects (SDL_Renderer *renderer, const SDL_FRect *rects, int count)
 
int SDL_RenderTexture (SDL_Renderer *renderer, SDL_Texture *texture, const SDL_Rect *srcrect, const SDL_FRect *dstrect)
 
int SDL_RenderTextureRotated (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)
 
int SDL_RenderGeometry (SDL_Renderer *renderer, SDL_Texture *texture, const SDL_Vertex *vertices, int num_vertices, const int *indices, int num_indices)
 
int SDL_RenderGeometryRaw (SDL_Renderer *renderer, SDL_Texture *texture, const float *xy, int xy_stride, const SDL_Color *color, int color_stride, const float *uv, int uv_stride, int num_vertices, const void *indices, int num_indices, int size_indices)
 
int SDL_RenderReadPixels (SDL_Renderer *renderer, const SDL_Rect *rect, Uint32 format, void *pixels, int pitch)
 
int SDL_RenderPresent (SDL_Renderer *renderer)
 
void SDL_DestroyTexture (SDL_Texture *texture)
 
void SDL_DestroyRenderer (SDL_Renderer *renderer)
 
int SDL_RenderFlush (SDL_Renderer *renderer)
 
int SDL_GL_BindTexture (SDL_Texture *texture, float *texw, float *texh)
 
int SDL_GL_UnbindTexture (SDL_Texture *texture)
 
voidSDL_GetRenderMetalLayer (SDL_Renderer *renderer)
 
voidSDL_GetRenderMetalCommandEncoder (SDL_Renderer *renderer)
 
int SDL_SetRenderVSync (SDL_Renderer *renderer, int vsync)
 
int SDL_GetRenderVSync (SDL_Renderer *renderer, int *vsync)
 

Detailed Description

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

Definition in file SDL_render.h.

Typedef Documentation

◆ SDL_Renderer

typedef struct SDL_Renderer SDL_Renderer

Definition at line 154 of file SDL_render.h.

◆ SDL_Texture

typedef struct SDL_Texture SDL_Texture

Definition at line 160 of file SDL_render.h.

Enumeration Type Documentation

◆ SDL_RendererFlags

Flags used when creating a rendering context

Enumerator
SDL_RENDERER_SOFTWARE 

The renderer is a software fallback

SDL_RENDERER_ACCELERATED 

The renderer uses hardware acceleration

SDL_RENDERER_PRESENTVSYNC 

Present is synchronized with the refresh rate

Definition at line 65 of file SDL_render.h.

66{
67 SDL_RENDERER_SOFTWARE = 0x00000001, /**< The renderer is a software fallback */
68 SDL_RENDERER_ACCELERATED = 0x00000002, /**< The renderer uses hardware
69 acceleration */
70 SDL_RENDERER_PRESENTVSYNC = 0x00000004, /**< Present is synchronized
71 with the refresh rate */
SDL_RendererFlags
Definition: SDL_render.h:66
@ SDL_RENDERER_SOFTWARE
Definition: SDL_render.h:67
@ SDL_RENDERER_ACCELERATED
Definition: SDL_render.h:68
@ SDL_RENDERER_PRESENTVSYNC
Definition: SDL_render.h:70

◆ SDL_RendererFlip

Flip constants for SDL_RenderTextureRotated

Enumerator
SDL_FLIP_NONE 

Do not flip

SDL_FLIP_HORIZONTAL 

flip horizontally

SDL_FLIP_VERTICAL 

flip vertically

Definition at line 130 of file SDL_render.h.

131{
132 SDL_FLIP_NONE = 0x00000000, /**< Do not flip */
133 SDL_FLIP_HORIZONTAL = 0x00000001, /**< flip horizontally */
134 SDL_FLIP_VERTICAL = 0x00000002 /**< flip vertically */
SDL_RendererFlip
Definition: SDL_render.h:131
@ SDL_FLIP_VERTICAL
Definition: SDL_render.h:134
@ SDL_FLIP_NONE
Definition: SDL_render.h:132
@ SDL_FLIP_HORIZONTAL
Definition: SDL_render.h:133

◆ SDL_RendererLogicalPresentation

How the logical size is mapped to the output

Enumerator
SDL_LOGICAL_PRESENTATION_DISABLED 

There is no logical size in effect

SDL_LOGICAL_PRESENTATION_MATCH 

The rendered content matches the window size in screen coordinates

SDL_LOGICAL_PRESENTATION_STRETCH 

The rendered content is stretched to the output resolution

SDL_LOGICAL_PRESENTATION_LETTERBOX 

The rendered content is fit to the largest dimension and the other dimension is letterboxed with black bars

SDL_LOGICAL_PRESENTATION_OVERSCAN 

The rendered content is fit to the smallest dimension and the other dimension extends beyond the output bounds

SDL_LOGICAL_PRESENTATION_INTEGER_SCALE 

The rendered content is scaled up by integer multiples to fit the output resolution

Definition at line 140 of file SDL_render.h.

141{
142 SDL_LOGICAL_PRESENTATION_DISABLED, /**< There is no logical size in effect */
143 SDL_LOGICAL_PRESENTATION_MATCH, /**< The rendered content matches the window size in screen coordinates */
144 SDL_LOGICAL_PRESENTATION_STRETCH, /**< The rendered content is stretched to the output resolution */
145 SDL_LOGICAL_PRESENTATION_LETTERBOX, /**< The rendered content is fit to the largest dimension and the other dimension is letterboxed with black bars */
146 SDL_LOGICAL_PRESENTATION_OVERSCAN, /**< The rendered content is fit to the smallest dimension and the other dimension extends beyond the output bounds */
147 SDL_LOGICAL_PRESENTATION_INTEGER_SCALE, /**< The rendered content is scaled up by integer multiples to fit the output resolution */
SDL_RendererLogicalPresentation
Definition: SDL_render.h:141
@ SDL_LOGICAL_PRESENTATION_LETTERBOX
Definition: SDL_render.h:145
@ SDL_LOGICAL_PRESENTATION_MATCH
Definition: SDL_render.h:143
@ SDL_LOGICAL_PRESENTATION_DISABLED
Definition: SDL_render.h:142
@ SDL_LOGICAL_PRESENTATION_OVERSCAN
Definition: SDL_render.h:146
@ SDL_LOGICAL_PRESENTATION_STRETCH
Definition: SDL_render.h:144
@ SDL_LOGICAL_PRESENTATION_INTEGER_SCALE
Definition: SDL_render.h:147

◆ SDL_ScaleMode

The scaling mode for a texture.

Enumerator
SDL_SCALEMODE_NEAREST 

nearest pixel sampling

SDL_SCALEMODE_LINEAR 

linear filtering

SDL_SCALEMODE_BEST 

anisotropic filtering

Definition at line 100 of file SDL_render.h.

101{
102 SDL_SCALEMODE_NEAREST, /**< nearest pixel sampling */
103 SDL_SCALEMODE_LINEAR, /**< linear filtering */
104 SDL_SCALEMODE_BEST /**< anisotropic filtering */
SDL_ScaleMode
Definition: SDL_render.h:101
@ SDL_SCALEMODE_LINEAR
Definition: SDL_render.h:103
@ SDL_SCALEMODE_NEAREST
Definition: SDL_render.h:102
@ SDL_SCALEMODE_BEST
Definition: SDL_render.h:104

◆ SDL_TextureAccess

The access pattern allowed for a texture.

Enumerator
SDL_TEXTUREACCESS_STATIC 

Changes rarely, not lockable

SDL_TEXTUREACCESS_STREAMING 

Changes frequently, lockable

SDL_TEXTUREACCESS_TARGET 

Texture can be used as a render target

Definition at line 110 of file SDL_render.h.

111{
112 SDL_TEXTUREACCESS_STATIC, /**< Changes rarely, not lockable */
113 SDL_TEXTUREACCESS_STREAMING, /**< Changes frequently, lockable */
114 SDL_TEXTUREACCESS_TARGET /**< Texture can be used as a render target */
SDL_TextureAccess
Definition: SDL_render.h:111
@ SDL_TEXTUREACCESS_STATIC
Definition: SDL_render.h:112
@ SDL_TEXTUREACCESS_STREAMING
Definition: SDL_render.h:113
@ SDL_TEXTUREACCESS_TARGET
Definition: SDL_render.h:114

◆ SDL_TextureModulate

The texture channel modulation used in SDL_RenderTexture().

Enumerator
SDL_TEXTUREMODULATE_NONE 

No modulation

SDL_TEXTUREMODULATE_COLOR 

srcC = srcC * color

SDL_TEXTUREMODULATE_ALPHA 

srcA = srcA * alpha

Definition at line 120 of file SDL_render.h.

121{
122 SDL_TEXTUREMODULATE_NONE = 0x00000000, /**< No modulation */
123 SDL_TEXTUREMODULATE_COLOR = 0x00000001, /**< srcC = srcC * color */
124 SDL_TEXTUREMODULATE_ALPHA = 0x00000002 /**< srcA = srcA * alpha */
SDL_TextureModulate
Definition: SDL_render.h:121
@ SDL_TEXTUREMODULATE_NONE
Definition: SDL_render.h:122
@ SDL_TEXTUREMODULATE_ALPHA
Definition: SDL_render.h:124
@ SDL_TEXTUREMODULATE_COLOR
Definition: SDL_render.h:123

Function Documentation

◆ SDL_ConvertEventToRenderCoordinates()

int SDL_ConvertEventToRenderCoordinates ( SDL_Renderer renderer,
SDL_Event event 
)

Convert the coordinates in an event to render coordinates.

Touch coordinates are converted from normalized coordinates in the window to non-normalized rendering coordinates.

Once converted, the coordinates may be outside the rendering area.

Parameters
rendererthe rendering context
eventthe event to modify
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_GetRenderCoordinatesFromWindowCoordinates

◆ SDL_CreateRenderer()

SDL_Renderer * SDL_CreateRenderer ( SDL_Window window,
const char *  name,
Uint32  flags 
)

Create a 2D rendering context for a window.

If you want a specific renderer, you can specify its name here. A list of available renderers can be obtained by calling SDL_GetRenderDriver multiple times, with indices from 0 to SDL_GetNumRenderDrivers()-1. If you don't need a specific renderer, specify NULL and SDL will attempt to chooes the best option for you, based on what is available on the user's system.

By default the rendering size matches the window size in screen coordinates, but you can call SDL_SetRenderLogicalPresentation() to enable high DPI rendering or change the content size and scaling options.

Parameters
windowthe window where rendering is displayed
namethe name of the rendering driver to initialize, or NULL to initialize the first one supporting the requested flags
flags0, 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.
Since
This function is available since SDL 3.0.0.
See also
SDL_CreateSoftwareRenderer
SDL_DestroyRenderer
SDL_GetNumRenderDrivers
SDL_GetRenderDriver
SDL_GetRendererInfo

◆ SDL_CreateSoftwareRenderer()

SDL_Renderer * SDL_CreateSoftwareRenderer ( SDL_Surface surface)

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.

Parameters
surfacethe 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.
Since
This function is available since SDL 3.0.0.
See also
SDL_CreateRenderer
SDL_CreateWindowRenderer
SDL_DestroyRenderer

◆ SDL_CreateTexture()

SDL_Texture * SDL_CreateTexture ( SDL_Renderer renderer,
Uint32  format,
int  access,
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.

Parameters
rendererthe rendering context
formatone of the enumerated values in SDL_PixelFormatEnum
accessone of the enumerated values in SDL_TextureAccess
wthe width of the texture in pixels
hthe 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.
Since
This function is available since SDL 3.0.0.
See also
SDL_CreateTextureFromSurface
SDL_DestroyTexture
SDL_QueryTexture
SDL_UpdateTexture

◆ SDL_CreateTextureFromSurface()

SDL_Texture * SDL_CreateTextureFromSurface ( SDL_Renderer renderer,
SDL_Surface surface 
)

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.

Parameters
rendererthe rendering context
surfacethe 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.
Since
This function is available since SDL 3.0.0.
See also
SDL_CreateTexture
SDL_DestroyTexture
SDL_QueryTexture

◆ SDL_CreateWindowAndRenderer()

int SDL_CreateWindowAndRenderer ( int  width,
int  height,
Uint32  window_flags,
SDL_Window **  window,
SDL_Renderer **  renderer 
)

Create a window and default renderer.

Parameters
widththe width of the window
heightthe height of the window
window_flagsthe flags used to create the window (see SDL_CreateWindow())
windowa pointer filled with the window, or NULL on error
renderera pointer filled with the renderer, or NULL on error
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_CreateRenderer
SDL_CreateWindow

◆ SDL_DestroyRenderer()

void SDL_DestroyRenderer ( SDL_Renderer renderer)

Destroy the rendering context for a window and free associated textures.

If renderer is NULL, this function will return immediately after setting the SDL error message to "Invalid renderer". See SDL_GetError().

Parameters
rendererthe rendering context
Since
This function is available since SDL 3.0.0.
See also
SDL_CreateRenderer

◆ SDL_DestroyTexture()

void SDL_DestroyTexture ( SDL_Texture texture)

Destroy the specified texture.

Passing NULL or an otherwise invalid texture will set the SDL error message to "Invalid texture".

Parameters
texturethe texture to destroy
Since
This function is available since SDL 3.0.0.
See also
SDL_CreateTexture
SDL_CreateTextureFromSurface

◆ SDL_GetCurrentRenderOutputSize()

int SDL_GetCurrentRenderOutputSize ( SDL_Renderer renderer,
int *  w,
int *  h 
)

Get the current output size in pixels of a rendering context.

If a rendering target is active, this will return the size of the rendering target in pixels, otherwise if a logical size is set, it will return the logical size, otherwise it will return the value of SDL_GetRenderOutputSize().

Parameters
rendererthe rendering context
wa pointer filled in with the current width
ha pointer filled in with the current 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 3.0.0.
See also
SDL_GetRenderOutputSize
SDL_GetRenderer

◆ SDL_GetNumRenderDrivers()

int SDL_GetNumRenderDrivers ( void  )

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 3.0.0.
See also
SDL_CreateRenderer
SDL_GetRenderDriver

◆ SDL_GetRenderClipRect()

int SDL_GetRenderClipRect ( SDL_Renderer renderer,
SDL_Rect rect 
)

Get the clip rectangle for the current target.

Parameters
rendererthe rendering context
rectan SDL_Rect structure filled in with the current clipping area or an empty rectangle if clipping is disabled
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_RenderClipEnabled
SDL_SetRenderClipRect

◆ SDL_GetRenderDrawBlendMode()

int SDL_GetRenderDrawBlendMode ( SDL_Renderer renderer,
SDL_BlendMode blendMode 
)

Get the blend mode used for drawing operations.

Parameters
rendererthe rendering context
blendModea 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.
Since
This function is available since SDL 3.0.0.
See also
SDL_SetRenderDrawBlendMode

◆ SDL_GetRenderDrawColor()

int SDL_GetRenderDrawColor ( SDL_Renderer renderer,
Uint8 r,
Uint8 g,
Uint8 b,
Uint8 a 
)

Get the color used for drawing operations (Rect, Line and Clear).

Parameters
rendererthe rendering context
ra pointer filled in with the red value used to draw on the rendering target
ga pointer filled in with the green value used to draw on the rendering target
ba pointer filled in with the blue value used to draw on the rendering target
aa 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.
Since
This function is available since SDL 3.0.0.
See also
SDL_SetRenderDrawColor

◆ SDL_GetRenderDriver()

const char * SDL_GetRenderDriver ( int  index)

Use this function to get the name of a built in 2D rendering driver.

The list of rendering drivers is given in the order that they are normally initialized by default; the drivers that seem more reasonable to choose first (as far as the SDL developers believe) are earlier in the list.

The names of drivers are all simple, low-ASCII identifiers, like "opengl", "direct3d12" or "metal". These never have Unicode characters, and are not meant to be proper names.

The returned value points to a static, read-only string; do not modify or free it!

Parameters
indexthe index of the rendering driver; the value ranges from 0 to SDL_GetNumRenderDrivers() - 1
Returns
the name of the rendering driver at the requested index, or NULL if an invalid index was specified.
Since
This function is available since SDL 3.0.0.
See also
SDL_GetNumRenderDrivers

◆ SDL_GetRenderer()

SDL_Renderer * SDL_GetRenderer ( SDL_Window window)

Get the renderer associated with a window.

Parameters
windowthe window to query
Returns
the rendering context on success or NULL on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_CreateRenderer

◆ SDL_GetRendererInfo()

int SDL_GetRendererInfo ( SDL_Renderer renderer,
SDL_RendererInfo info 
)

Get information about a rendering context.

Parameters
rendererthe rendering context
infoan 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.
Since
This function is available since SDL 3.0.0.
See also
SDL_CreateRenderer

◆ SDL_GetRenderLogicalPresentation()

int SDL_GetRenderLogicalPresentation ( SDL_Renderer renderer,
int *  w,
int *  h,
SDL_RendererLogicalPresentation mode,
SDL_ScaleMode scale_mode 
)

Get device independent resolution and presentation mode for rendering.

This function gets the width and height of the logical rendering output, or the output size in pixels if a logical resolution is not enabled.

Parameters
rendererthe rendering context
wan int to be filled with the width
han int to be filled with the height
modea pointer filled in with the presentation mode
scale_modea pointer filled in with the scale mode
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_SetRenderLogicalPresentation

◆ SDL_GetRenderMetalCommandEncoder()

void * SDL_GetRenderMetalCommandEncoder ( 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>.

Note that as of SDL 2.0.18, this will return NULL if Metal refuses to give SDL a drawable to render to, which might happen if the window is hidden/minimized/offscreen. This doesn't apply to command encoders for render targets, just the window's backbacker. Check your return values!

Parameters
rendererThe renderer to query
Returns
an id<MTLRenderCommandEncoder> on success, or NULL if the renderer isn't a Metal renderer or there was an error.
Since
This function is available since SDL 3.0.0.
See also
SDL_GetRenderMetalLayer

◆ SDL_GetRenderMetalLayer()

void * SDL_GetRenderMetalLayer ( SDL_Renderer renderer)

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 *.

Parameters
rendererThe renderer to query
Returns
a CAMetalLayer * on success, or NULL if the renderer isn't a Metal renderer
Since
This function is available since SDL 3.0.0.
See also
SDL_GetRenderMetalCommandEncoder

◆ SDL_GetRenderOutputSize()

int SDL_GetRenderOutputSize ( SDL_Renderer renderer,
int *  w,
int *  h 
)

Get the output size in pixels of a rendering context.

This returns the true output size in pixels, ignoring any render targets or logical size and presentation.

Parameters
rendererthe rendering context
wa pointer filled in with the width in pixels
ha pointer filled in with the height in pixels
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_GetRenderer

◆ SDL_GetRenderScale()

int SDL_GetRenderScale ( SDL_Renderer renderer,
float *  scaleX,
float *  scaleY 
)

Get the drawing scale for the current target.

Parameters
rendererthe rendering context
scaleXa pointer filled in with the horizontal scaling factor
scaleYa pointer filled in with 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 3.0.0.
See also
SDL_SetRenderScale

◆ SDL_GetRenderTarget()

SDL_Texture * SDL_GetRenderTarget ( SDL_Renderer renderer)

Get the current render target.

The default render target is the window for which the renderer was created, and is reported a NULL here.

Parameters
rendererthe rendering context
Returns
the current render target or NULL for the default render target.
Since
This function is available since SDL 3.0.0.
See also
SDL_SetRenderTarget

◆ SDL_GetRenderViewport()

int SDL_GetRenderViewport ( SDL_Renderer renderer,
SDL_Rect rect 
)

Get the drawing area for the current target.

Parameters
rendererthe rendering context
rectan SDL_Rect structure filled in with the current drawing area
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_SetRenderViewport

◆ SDL_GetRenderVSync()

int SDL_GetRenderVSync ( SDL_Renderer renderer,
int *  vsync 
)

Get VSync of the given renderer.

Parameters
rendererThe renderer to toggle
vsyncan int filled with 1 for on, 0 for off. All other values are reserved
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_GetRenderWindow()

SDL_Window * SDL_GetRenderWindow ( SDL_Renderer renderer)

Get the window associated with a renderer.

Parameters
rendererthe renderer to query
Returns
the window on success or NULL on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_GetRenderWindowSize()

int SDL_GetRenderWindowSize ( SDL_Renderer renderer,
int *  w,
int *  h 
)

Get the output size in screen coordinates of a rendering context.

This returns the true output size in screen coordinates, ignoring any render targets or logical size and presentation.

Parameters
rendererthe rendering context
wa pointer filled in with the width in screen coordinates
ha pointer filled in with the height in screen coordinates
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_GetRenderer

◆ SDL_GetTextureAlphaMod()

int SDL_GetTextureAlphaMod ( SDL_Texture texture,
Uint8 alpha 
)

Get the additional alpha value multiplied into render copy operations.

Parameters
texturethe texture to query
alphaa 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.
Since
This function is available since SDL 3.0.0.
See also
SDL_GetTextureColorMod
SDL_SetTextureAlphaMod

◆ SDL_GetTextureBlendMode()

int SDL_GetTextureBlendMode ( SDL_Texture texture,
SDL_BlendMode blendMode 
)

Get the blend mode used for texture copy operations.

Parameters
texturethe texture to query
blendModea 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.
Since
This function is available since SDL 3.0.0.
See also
SDL_SetTextureBlendMode

◆ SDL_GetTextureColorMod()

int SDL_GetTextureColorMod ( SDL_Texture texture,
Uint8 r,
Uint8 g,
Uint8 b 
)

Get the additional color value multiplied into render copy operations.

Parameters
texturethe texture to query
ra pointer filled in with the current red color value
ga pointer filled in with the current green color value
ba 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.
Since
This function is available since SDL 3.0.0.
See also
SDL_GetTextureAlphaMod
SDL_SetTextureColorMod

◆ SDL_GetTextureScaleMode()

int SDL_GetTextureScaleMode ( SDL_Texture texture,
SDL_ScaleMode scaleMode 
)

Get the scale mode used for texture scale operations.

Parameters
texturethe texture to query.
scaleModea pointer filled in with the current scale mode.
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_SetTextureScaleMode

◆ SDL_GetTextureUserData()

void * SDL_GetTextureUserData ( SDL_Texture texture)

Get the user-specified pointer associated with a texture

Parameters
texturethe texture to query.
Returns
the pointer associated with the texture, or NULL if the texture is not valid.
Since
This function is available since SDL 3.0.0.
See also
SDL_SetTextureUserData

◆ SDL_GL_BindTexture()

int SDL_GL_BindTexture ( SDL_Texture texture,
float *  texw,
float *  texh 
)

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.

Parameters
texturethe texture to bind to the current OpenGL/ES/ES2 context
texwa pointer to a float value which will be filled with the texture width or NULL if you don't need that value
texha 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 a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_GL_MakeCurrent
SDL_GL_UnbindTexture

◆ SDL_GL_UnbindTexture()

int SDL_GL_UnbindTexture ( SDL_Texture texture)

Unbind an OpenGL/ES/ES2 texture from the current context.

See SDL_GL_BindTexture() for examples on how to use these functions

Parameters
texturethe texture to unbind from the current OpenGL/ES/ES2 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 3.0.0.
See also
SDL_GL_BindTexture
SDL_GL_MakeCurrent

◆ SDL_LockTexture()

int SDL_LockTexture ( SDL_Texture texture,
const SDL_Rect rect,
void **  pixels,
int *  pitch 
)

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.

Parameters
texturethe texture to lock for access, which was created with SDL_TEXTUREACCESS_STREAMING
rectan SDL_Rect structure representing the area to lock for access; NULL to lock the entire texture
pixelsthis is filled in with a pointer to the locked pixels, appropriately offset by the locked area
pitchthis 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.
Since
This function is available since SDL 3.0.0.
See also
SDL_UnlockTexture

◆ SDL_LockTextureToSurface()

int SDL_LockTextureToSurface ( SDL_Texture texture,
const SDL_Rect rect,
SDL_Surface **  surface 
)

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.

Parameters
texturethe texture to lock for access, which must be created with SDL_TEXTUREACCESS_STREAMING
recta pointer to the rectangle to lock for access. If the rect is NULL, the entire texture will be locked
surfacethis is filled in with an SDL surface representing the locked area
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_LockTexture
SDL_UnlockTexture

◆ SDL_QueryTexture()

int SDL_QueryTexture ( SDL_Texture texture,
Uint32 format,
int *  access,
int *  w,
int *  h 
)

Query the attributes of a texture.

Parameters
texturethe texture to query
formata 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). This argument can be NULL if you don't need this information.
accessa pointer filled in with the actual access to the texture (one of the SDL_TextureAccess values). This argument can be NULL if you don't need this information.
wa pointer filled in with the width of the texture in pixels. This argument can be NULL if you don't need this information.
ha pointer filled in with the height of the texture in pixels. This argument can be NULL if you don't need this information.
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_CreateTexture

◆ SDL_RenderClear()

int SDL_RenderClear ( SDL_Renderer renderer)

Clear the current rendering target with the drawing color.

This function clears the entire rendering target, ignoring the viewport and the clip rectangle.

Parameters
rendererthe 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 3.0.0.
See also
SDL_SetRenderDrawColor

◆ SDL_RenderClipEnabled()

SDL_bool SDL_RenderClipEnabled ( SDL_Renderer renderer)

Get whether clipping is enabled on the given renderer.

Parameters
rendererthe rendering context
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 3.0.0.
See also
SDL_GetRenderClipRect
SDL_SetRenderClipRect

◆ SDL_RenderCoordinatesFromWindow()

int SDL_RenderCoordinatesFromWindow ( SDL_Renderer renderer,
float  window_x,
float  window_y,
float *  x,
float *  y 
)

Get a point in render coordinates when given a point in window coordinates.

Parameters
rendererthe rendering context
window_xthe x coordinate in window coordinates
window_ythe y coordinate in window coordinates
xa pointer filled with the x coordinate in render coordinates
ya pointer filled with the y coordinate in render coordinates
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_SetRenderLogicalPresentation
SDL_SetRenderScale

◆ SDL_RenderCoordinatesToWindow()

int SDL_RenderCoordinatesToWindow ( SDL_Renderer renderer,
float  x,
float  y,
float *  window_x,
float *  window_y 
)

Get a point in window coordinates when given a point in render coordinates.

Parameters
rendererthe rendering context
xthe x coordinate in render coordinates
ythe y coordinate in render coordinates
window_xa pointer filled with the x coordinate in window coordinates
window_ya pointer filled with the y coordinate in window coordinates
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_SetRenderLogicalPresentation
SDL_SetRenderScale

◆ SDL_RenderFillRect()

int SDL_RenderFillRect ( SDL_Renderer renderer,
const SDL_FRect rect 
)

Fill a rectangle on the current rendering target with the drawing color at subpixel precision.

Parameters
rendererThe renderer which should fill a rectangle.
rectA pointer to the destination rectangle, or NULL for the entire rendering target.
Returns
0 on success, or -1 on error
Since
This function is available since SDL 3.0.0.

◆ SDL_RenderFillRects()

int SDL_RenderFillRects ( SDL_Renderer renderer,
const SDL_FRect rects,
int  count 
)

Fill some number of rectangles on the current rendering target with the drawing color at subpixel precision.

Parameters
rendererThe renderer which should fill multiple rectangles.
rectsA pointer to an array of destination rectangles.
countThe number of rectangles.
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_RenderFlush()

int SDL_RenderFlush ( 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.

Parameters
rendererthe 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 3.0.0.

◆ SDL_RenderGeometry()

int SDL_RenderGeometry ( SDL_Renderer renderer,
SDL_Texture texture,
const SDL_Vertex vertices,
int  num_vertices,
const int *  indices,
int  num_indices 
)

Render a list of triangles, optionally using a texture and indices into the vertex array Color and alpha modulation is done per vertex (SDL_SetTextureColorMod and SDL_SetTextureAlphaMod are ignored).

Parameters
rendererThe rendering context.
texture(optional) The SDL texture to use.
verticesVertices.
num_verticesNumber of vertices.
indices(optional) An array of integer indices into the 'vertices' array, if NULL all vertices will be rendered in sequential order.
num_indicesNumber of indices.
Returns
0 on success, or -1 if the operation is not supported
Since
This function is available since SDL 3.0.0.
See also
SDL_RenderGeometryRaw
SDL_Vertex

◆ SDL_RenderGeometryRaw()

int SDL_RenderGeometryRaw ( SDL_Renderer renderer,
SDL_Texture texture,
const float *  xy,
int  xy_stride,
const SDL_Color color,
int  color_stride,
const float *  uv,
int  uv_stride,
int  num_vertices,
const void indices,
int  num_indices,
int  size_indices 
)

Render a list of triangles, optionally using a texture and indices into the vertex arrays Color and alpha modulation is done per vertex (SDL_SetTextureColorMod and SDL_SetTextureAlphaMod are ignored).

Parameters
rendererThe rendering context.
texture(optional) The SDL texture to use.
xyVertex positions
xy_strideByte size to move from one element to the next element
colorVertex colors (as SDL_Color)
color_strideByte size to move from one element to the next element
uvVertex normalized texture coordinates
uv_strideByte size to move from one element to the next element
num_verticesNumber of vertices.
indices(optional) An array of indices into the 'vertices' arrays, if NULL all vertices will be rendered in sequential order.
num_indicesNumber of indices.
size_indicesIndex size: 1 (byte), 2 (short), 4 (int)
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_RenderGeometry
SDL_Vertex

◆ SDL_RenderLine()

int SDL_RenderLine ( SDL_Renderer renderer,
float  x1,
float  y1,
float  x2,
float  y2 
)

Draw a line on the current rendering target at subpixel precision.

Parameters
rendererThe renderer which should draw a line.
x1The x coordinate of the start point.
y1The y coordinate of the start point.
x2The x coordinate of the end point.
y2The y coordinate of the end point.
Returns
0 on success, or -1 on error
Since
This function is available since SDL 3.0.0.

◆ SDL_RenderLines()

int SDL_RenderLines ( SDL_Renderer renderer,
const SDL_FPoint points,
int  count 
)

Draw a series of connected lines on the current rendering target at subpixel precision.

Parameters
rendererThe renderer which should draw multiple lines.
pointsThe points along the lines
countThe 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 3.0.0.

◆ SDL_RenderPoint()

int SDL_RenderPoint ( SDL_Renderer renderer,
float  x,
float  y 
)

Draw a point on the current rendering target at subpixel precision.

Parameters
rendererThe renderer which should draw a point.
xThe x coordinate of the point.
yThe y coordinate of the point.
Returns
0 on success, or -1 on error
Since
This function is available since SDL 3.0.0.

◆ SDL_RenderPoints()

int SDL_RenderPoints ( SDL_Renderer renderer,
const SDL_FPoint points,
int  count 
)

Draw multiple points on the current rendering target at subpixel precision.

Parameters
rendererThe renderer which should draw multiple points.
pointsThe points to draw
countThe number of points to draw
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_RenderPresent()

int SDL_RenderPresent ( SDL_Renderer renderer)

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_RenderLine() 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.

Parameters
rendererthe rendering context
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.

\threadsafety You may only call this function on the main thread.

Since
This function is available since SDL 3.0.0.
See also
SDL_RenderClear
SDL_RenderLine
SDL_RenderLines
SDL_RenderPoint
SDL_RenderPoints
SDL_RenderRect
SDL_RenderRects
SDL_RenderFillRect
SDL_RenderFillRects
SDL_SetRenderDrawBlendMode
SDL_SetRenderDrawColor

◆ SDL_RenderReadPixels()

int SDL_RenderReadPixels ( SDL_Renderer renderer,
const SDL_Rect rect,
Uint32  format,
void pixels,
int  pitch 
)

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. If you're using this on the main rendering target, it should be called after rendering and before SDL_RenderPresent().

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).

Parameters
rendererthe rendering context
rectan SDL_Rect structure representing the area in pixels relative to the to current viewport, or NULL for the entire viewport
formatan SDL_PixelFormatEnum value of the desired format of the pixel data, or 0 to use the format of the rendering target
pixelsa pointer to the pixel data to copy into
pitchthe pitch of the pixels parameter
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_RenderRect()

int SDL_RenderRect ( SDL_Renderer renderer,
const SDL_FRect rect 
)

Draw a rectangle on the current rendering target at subpixel precision.

Parameters
rendererThe renderer which should draw a rectangle.
rectA pointer to the destination rectangle, or NULL to outline the entire rendering target.
Returns
0 on success, or -1 on error
Since
This function is available since SDL 3.0.0.

◆ SDL_RenderRects()

int SDL_RenderRects ( SDL_Renderer renderer,
const SDL_FRect rects,
int  count 
)

Draw some number of rectangles on the current rendering target at subpixel precision.

Parameters
rendererThe renderer which should draw multiple rectangles.
rectsA pointer to an array of destination rectangles.
countThe number of rectangles.
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_RenderTexture()

int SDL_RenderTexture ( SDL_Renderer renderer,
SDL_Texture texture,
const SDL_Rect srcrect,
const SDL_FRect dstrect 
)

Copy a portion of the texture to the current rendering target at subpixel precision.

Parameters
rendererThe renderer which should copy parts of a texture.
textureThe source texture.
srcrectA pointer to the source rectangle, or NULL for the entire texture.
dstrectA pointer to the destination rectangle, or NULL for the entire rendering target.
Returns
0 on success, or -1 on error
Since
This function is available since SDL 3.0.0.

◆ SDL_RenderTextureRotated()

int SDL_RenderTextureRotated ( 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 
)

Copy a portion of the source texture to the current rendering target, with rotation and flipping, at subpixel precision.

Parameters
rendererThe renderer which should copy parts of a texture.
textureThe source texture.
srcrectA pointer to the source rectangle, or NULL for the entire texture.
dstrectA pointer to the destination rectangle, or NULL for the entire rendering target.
angleAn angle in degrees that indicates the rotation that will be applied to dstrect, rotating it in a clockwise direction
centerA 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).
flipAn 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.
Since
This function is available since SDL 3.0.0.

◆ SDL_SetRenderClipRect()

int SDL_SetRenderClipRect ( SDL_Renderer renderer,
const SDL_Rect rect 
)

Set the clip rectangle for rendering on the specified target.

Parameters
rendererthe rendering context
rectan 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.
Since
This function is available since SDL 3.0.0.
See also
SDL_GetRenderClipRect
SDL_RenderClipEnabled

◆ SDL_SetRenderDrawBlendMode()

int SDL_SetRenderDrawBlendMode ( SDL_Renderer renderer,
SDL_BlendMode  blendMode 
)

Set the blend mode used for drawing operations (Fill and Line).

If the blend mode is not supported, the closest supported mode is chosen.

Parameters
rendererthe rendering context
blendModethe SDL_BlendMode to use for blending
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_GetRenderDrawBlendMode
SDL_RenderLine
SDL_RenderLines
SDL_RenderPoint
SDL_RenderPoints
SDL_RenderRect
SDL_RenderRects
SDL_RenderFillRect
SDL_RenderFillRects

◆ SDL_SetRenderDrawColor()

int SDL_SetRenderDrawColor ( SDL_Renderer renderer,
Uint8  r,
Uint8  g,
Uint8  b,
Uint8  a 
)

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().

Parameters
rendererthe rendering context
rthe red value used to draw on the rendering target
gthe green value used to draw on the rendering target
bthe blue value used to draw on the rendering target
athe 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.
Since
This function is available since SDL 3.0.0.
See also
SDL_GetRenderDrawColor
SDL_RenderClear
SDL_RenderLine
SDL_RenderLines
SDL_RenderPoint
SDL_RenderPoints
SDL_RenderRect
SDL_RenderRects
SDL_RenderFillRect
SDL_RenderFillRects

◆ SDL_SetRenderLogicalPresentation()

int SDL_SetRenderLogicalPresentation ( SDL_Renderer renderer,
int  w,
int  h,
SDL_RendererLogicalPresentation  mode,
SDL_ScaleMode  scale_mode 
)

Set a device independent resolution and presentation mode for rendering.

This function sets the width and height of the logical rendering output. A render target is created at the specified size and used for rendering and then copied to the output during presentation.

When a renderer is created, the logical size is set to match the window size in screen coordinates. The actual output size may be higher pixel density, and can be queried with SDL_GetRenderOutputSize().

You can disable logical coordinates by setting the mode to SDL_LOGICAL_PRESENTATION_DISABLED, and in that case you get the full resolution of the output window.

You can convert coordinates in an event into rendering coordinates using SDL_ConvertEventToRenderCoordinates().

Parameters
rendererthe rendering context
wthe width of the logical resolution
hthe height of the logical resolution
modethe presentation mode used
scale_modethe scale mode used
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_ConvertEventToRenderCoordinates
SDL_GetRenderLogicalPresentation

◆ SDL_SetRenderScale()

int SDL_SetRenderScale ( SDL_Renderer renderer,
float  scaleX,
float  scaleY 
)

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.

Parameters
rendererthe rendering context
scaleXthe horizontal scaling factor
scaleYthe 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 3.0.0.
See also
SDL_GetRenderScale

◆ SDL_SetRenderTarget()

int SDL_SetRenderTarget ( SDL_Renderer renderer,
SDL_Texture texture 
)

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.

Parameters
rendererthe rendering context
texturethe 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 3.0.0.
See also
SDL_GetRenderTarget

◆ SDL_SetRenderViewport()

int SDL_SetRenderViewport ( SDL_Renderer renderer,
const SDL_Rect rect 
)

Set the drawing area for rendering on the current target.

Parameters
rendererthe rendering context
rectthe 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.
Since
This function is available since SDL 3.0.0.
See also
SDL_GetRenderViewport

◆ SDL_SetRenderVSync()

int SDL_SetRenderVSync ( SDL_Renderer renderer,
int  vsync 
)

Toggle VSync of the given renderer.

Parameters
rendererThe renderer to toggle
vsync1 for on, 0 for off. All other values are reserved
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_SetTextureAlphaMod()

int SDL_SetTextureAlphaMod ( SDL_Texture texture,
Uint8  alpha 
)

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.

Parameters
texturethe texture to update
alphathe source alpha value multiplied into copy operations
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_GetTextureAlphaMod
SDL_SetTextureColorMod

◆ SDL_SetTextureBlendMode()

int SDL_SetTextureBlendMode ( SDL_Texture texture,
SDL_BlendMode  blendMode 
)

Set the blend mode for a texture, used by SDL_RenderTexture().

If the blend mode is not supported, the closest supported mode is chosen and this function returns -1.

Parameters
texturethe texture to update
blendModethe SDL_BlendMode to use for texture blending
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_GetTextureBlendMode
SDL_RenderTexture

◆ SDL_SetTextureColorMod()

int SDL_SetTextureColorMod ( SDL_Texture texture,
Uint8  r,
Uint8  g,
Uint8  b 
)

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.

Parameters
texturethe texture to update
rthe red color value multiplied into copy operations
gthe green color value multiplied into copy operations
bthe blue color value multiplied into copy operations
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_GetTextureColorMod
SDL_SetTextureAlphaMod

◆ SDL_SetTextureScaleMode()

int SDL_SetTextureScaleMode ( SDL_Texture texture,
SDL_ScaleMode  scaleMode 
)

Set the scale mode used for texture scale operations.

If the scale mode is not supported, the closest supported mode is chosen.

Parameters
textureThe texture to update.
scaleModethe SDL_ScaleMode to use for texture scaling.
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_GetTextureScaleMode

◆ SDL_SetTextureUserData()

int SDL_SetTextureUserData ( SDL_Texture texture,
void userdata 
)

Associate a user-specified pointer with a texture.

Parameters
texturethe texture to update.
userdatathe pointer to associate with the 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 3.0.0.
See also
SDL_GetTextureUserData

◆ SDL_UnlockTexture()

void SDL_UnlockTexture ( SDL_Texture texture)

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 not guarantee 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.

Parameters
texturea texture locked by SDL_LockTexture()
Since
This function is available since SDL 3.0.0.
See also
SDL_LockTexture

◆ SDL_UpdateNVTexture()

int SDL_UpdateNVTexture ( SDL_Texture texture,
const SDL_Rect rect,
const Uint8 Yplane,
int  Ypitch,
const Uint8 UVplane,
int  UVpitch 
)

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.

Parameters
texturethe texture to update
recta pointer to the rectangle of pixels to update, or NULL to update the entire texture.
Yplanethe raw pixel data for the Y plane.
Ypitchthe number of bytes between rows of pixel data for the Y plane.
UVplanethe raw pixel data for the UV plane.
UVpitchthe number of bytes between rows of pixel data for the UV plane.
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_UpdateTexture()

int SDL_UpdateTexture ( SDL_Texture texture,
const SDL_Rect rect,
const void pixels,
int  pitch 
)

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.

Parameters
texturethe texture to update
rectan SDL_Rect structure representing the area to update, or NULL to update the entire texture
pixelsthe raw pixel data in the format of the texture
pitchthe 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.
Since
This function is available since SDL 3.0.0.
See also
SDL_CreateTexture
SDL_LockTexture
SDL_UnlockTexture

◆ SDL_UpdateYUVTexture()

int 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 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.

Parameters
texturethe texture to update
recta pointer to the rectangle of pixels to update, or NULL to update the entire texture
Yplanethe raw pixel data for the Y plane
Ypitchthe number of bytes between rows of pixel data for the Y plane
Uplanethe raw pixel data for the U plane
Upitchthe number of bytes between rows of pixel data for the U plane
Vplanethe raw pixel data for the V plane
Vpitchthe number of bytes between rows of pixel data for the V plane
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_UpdateTexture