Converts any floating point format to any indexed format.

procedure FloatToIndex(NumPixels: LongInt; 
                       Src: PByte; 
                       Dst: PByte; 
                       SrcInfo: PImageFormatInfo; 
                       DstInfo: PImageFormatInfo; 
                       DstPal: PPalette32);

ImagingFormats (at line 287)