title: SDL Basics: Textures vs. Images
body: <p>I'm writing some code that uses SDL2 to display an image with moving markers layered on it, and I think I'd like to use the new (?) 2D hardware accelerated rendering. As I understand it, I have to load an image and convert it to a texture -- but what's the difference? Searching for 'image texture 2d sdl' only gets me tutorials on how to load textures and I'm looking for more of the background rather than the how-to.</p>
  
  <p>So, some questions:</p>
  
  <ul>
  <li>What's a texture versus an image? Aren't they the same thing?</li>
  <li>Am I correct in assuming that I need to load the static background image as a texture if I want hardware accelerated rendering? In fact, it sounds like <em>all</em> the bits need to be textures for this to work.</li>
  <li>Speaking of OpenGL, are SDL textures actually OpenGL textures?</li>
  <li>I'm writing the main app for a single-purpose machine with limited resources (dual core ARM CPU, dual core Mali 400 GPU, 4GB RAM: <a href="https://www.olimex.com/Products/OLinuXino/A20/A20-OLinuXIno-LIME2/open-source-hardware" rel="nofollow">Olimex A20 LIME2</a>). All I need to do is render an 480x800 (yes, portrait layout) image and put markers on it. I expect the markers to have a single opaque and two transparency layers, to be updated at around 15 fps, and I expect about 125 of them, tops. Is it worth my while to use 2D hardware acceleration or should I just do it in software?</li>
  </ul>