What is the difference between SDL_RenderSetClipRect and SDL_RenderSetViewport. Those two wiki pages have a slightly different wording, but they seem to have the same meaning.
Most of the tutorials I have seen, they use viewports to draw differently on the screen. I plan to use it to draw onto textures which are clumped together into a few big atlas textures. However, either of the above functions alter the "current/specified target" of the renderer, which can be a texture.