Add text on VGA image

Hi,

I want to add some text informations on VGA images (frame rate, time...) and I am wondering what is the easiest way to do it.

My video system :

FPGA : input video => write/read in/from DDR2 with altmemphy DDR2 controller => vga output

I don't know where/when writing the text : in ddr after writing an image and before reading it, directly on vga video flux...

I don't how : nios, vhdl ?

I would like a configurable solution : enable/disable text, change position, choose displayed information...

any suggestion ?

thanks.