So - you are using PROGMEM for storage of the image?
The image can be somewhat moved by changing the reading address position of ROM.
However, being able to do is only such the thing,
If there were a way to modify the font, or have multiple fonts, that could open up some nice possibilities for games and such.
The file name of Character Generator code ( Font convert ) is "CG_20100316.h"
The data is arranged in order of ASCII code.
(the characters < 0x20 ) --> control code , so we place any charcters in the area.
Each charcters are made up by 6*8 dots.( = 6*8bits = 6bytes )
Conversion to V-RAM data from text data is performed at the time of the display of spacing line.
And three line is needed for conversion of 15 characters.
So, this method, The line - 3lines which nothing can display exists every 8 lines.
When you display it on the screen full,there is processing timing of the application only at vertically returning.
So you have to do all processing in a very narrow time-slice of the vertical blank. Could be an issue, depending on what is being done of course...
I'm sorry. I was not able to express it well in English.
So in such occasions (many tasks to do whithin a certain time ), We only have using a tricky technique.
CRT - interlaced scan is used. So, a picture is reflected even if it performs display processing every other time.
we can use the effect of the afterimage of CRT.
And processing time can be acquired.
The work ( NTSC with Arduino ) is an only exercise.
How to use AVR, how to use interrupt, timer, how to avoid jitter, etc.
and studuy NTSC signal.
Although full-scale image processing is treated, ATMEGA328P, capability is too low.
I think that it is the time when now CPLD and FPGA are used also in a hobby.
I want to cahllenge to handle FPGA and CPLD.....