XPLMDrawString

XPLM_API void                 XPLMDrawString(
                                   float *              inColorRGB,    
                                   int                  inXOffset,    
                                   int                  inYOffset,    
                                   char *               inChar,    
                                   int *                inWordWrapWidth,    /* Can be NULL */
                                   XPLMFontID           inFontID);    

This routine draws a NULL termianted string in a given font. Pass in the lower left pixel that the character is to be drawn onto. Also pass the character and font ID. This function returns the x offset plus the width of all drawn characters. The color to draw in is specified as a pointer to an array of three floating point colors, representing RGB intensities from 0.0 to 1.0.