(This is the documentation for SDL3, which is the current stable version. SDL2 was the previous version!)

SDL_LockTextureToSurface

Lock a portion of the texture for write-only pixel access, and expose it as a SDL surface.

Header File

Syntax

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

Function Parameters

SDL_Texture *	texture	the texture to lock for access, which must be created with `SDL_TEXTUREACCESS_STREAMING`.
const SDL_Rect *	rect	a pointer to the rectangle to lock for access. If the rect is NULL, the entire texture will be locked.
SDL_Surface **	surface	this is filled in with an SDL surface representing the locked area.

Return Value

(bool) Returns true on success or false on failure; call SDL_GetError() for more information.

Remarks

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.

Thread Safety

You may only call this function from the main thread.

Version

This function is available since SDL 3.1.3.