title: can a bmp image format handle transparency
body: <p>I am making this C++ program that has buttons, button containers, chat boxes, etc., and I want to wrap it around by textures.</p>
  
  <p>I want to generate a smooth edge for all the rectangles I made, and I don't want vertex plotting method to do the work for it, since it consumes more CPU usage and not that looks pretty good, and I don't know if it can work with texture coordinates(i.e. <em>glTexCoord(u, v)</em> with <em>glVertex2f(x, y)</em> w/c should only be 4 since it is a quad)</p>
  
  <p>I use to load textures using <strong>SDL_LoadBMP()</strong> w/c can load only a format of <em>.bmp</em>.(I'm not that sure because it says only LoadBMP there).</p>
  
  <h1>So my questions are:</h1>
  
  <ul>
  <li><p>can a <em>.bmp</em> format handle transparency? if so, how to do it?</p></li>
  <li><p>can you show me some code samples using <a href="http://www.lonesock.net/soil.html" rel="noreferrer">SOIL</a> to load image of format <em>.gif</em> or any other formats that can handle image transparency?</p></li>
  <li><p>can a quad handle an irregular/polygons shape like hexagon or star without drawing its background?</p></li>
  </ul>
  
  <h1>additional question</h1>
  
  <p>*how to import a primitive textbox that renders through c++ opengl so I can copy the texts there into clipboard? as for chatting session in my program.</p>
  
  <hr>
  
  <p>I made my own library that draws the text using GL_POINTS and doesn't look good when resizing the window because the points were spread-out. It takes <code>const char*</code> for the text to avoid <code>#include &lt;*string*&gt;</code> because I want my program to be not dependent on core functions of C++.</p>
  
  <p>So the better solution is to draw it using bitmaps.</p>
  
  <p>Some suggest to draw it using images so I really need the transparency thing because I want it to draw using quad only.</p>