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I need to clear a streaming texture before I draw into it on the next frame, because only a part is updated, and it's random enough that I can't predict which part will be clear.

I don't want to reinitialize it every time, or rewrite the whole texture each time.

Here is the code I tried, but this fails every time, since the texture is in streaming mode.

SDL_Texture* StreamingTexture = SDL_CreateTexture(render, SDL_PIXELFORMAT_RGBA8888, 
        SDL_TEXTUREACCESS_STREAMING, screen_width, screen_height);

SDL_SetRenderTarget(render, StreamingTexture);
SDL_SetRenderDrawColor(render, 0, 0, 0, 0);
SDL_RenderClear(render);
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  • \$\begingroup\$ Why are you using a streaming texture? \$\endgroup\$ – Tyyppi_77 Oct 11 '16 at 4:44
  • \$\begingroup\$ This feels like an XY problem. What are you actually trying to do here? \$\endgroup\$ – Tyyppi_77 Oct 11 '16 at 18:10
  • \$\begingroup\$ nah i got it :D \$\endgroup\$ – The guy Oct 11 '16 at 21:08
  • \$\begingroup\$ @Tyyppi_77 Essentially i need to write just few pixels, and i need to clear the texture, otherwise it makes this ghost effect. \$\endgroup\$ – The guy Oct 11 '16 at 21:15
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You just need to use SDL_FillRect:

SDLX_TextureLockSurface(Texture, Surface);
SDL_FillRect(Surface,NULL,SDLX_RGBAtoPixel(0,0,0,0)); // <<-- this is what clears entire texture 
SDLX_TextureUnlock(Texture); //LOOOOOCK !!!!!
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