XPLMGetTexture
From X-Plane SDK
XPLMGetTexture
XPLM_API int XPLMGetTexture( XPLMTextureID inTexture);
XPLMGetTexture returns the OpenGL texture enumeration of an X-Plane texture based on a generic identifying code. For example, you can get the texture for X-Plane's UI bitmaps. This allows you to build new gauges that take advantage of x-plane's textures, for smooth artwork integration and also saving texture memory. Note that the texture might not be loaded yet, depending on what the plane's panel contains.
OPEN ISSUE: We really need a way to make sure X-Plane loads this texture if it isn't around, or at least a way to find out whether it is loaded or not.