Re: help to create picture on memory and display on vga moni
I cannot help you much with this, but can give some clues as I am working with video and ram video right now.
To display some picture on video, you could use a ROM with the pattern. For altera, this can be acomplished defining some .mif file with the content of the ROM. For example:
Depth = 512;
Width = 8;
Address_radix = oct;
Data_radix = bin;
% Character Generator ROM Data %
Content
Begin
010 : 00011000 ; %---**----%
011 : 00111100 ; %--****--%
012 : 01100110 ; %-**--**-%
013 : 01111110 ; %-******-%
014 : 01100110 ; %-**--**-%
015 : 01100110 ; %-**--**-%
016 : 01100110 ; %-**--**-%
017 : 00000000 ; %---------%
To generate your own graphics, you may generate the pixels (bits) first in a RAM memory.
To show text characters on video, I am using two steps:
1. Generate the character code I want on RAM
2. The VGA controller reads the character code from RAM, calculate the address of the pattern on ROM, and show the pixels on the monitor
This is more or less complex. Very complex for me, because I am beginner with FPGA and VHDL.
But, as long as you proposed to implement OpenGL in a FPGA, I suppose you master graphics concepts.
Keep in mind that, for 3D graphics, you will need a VERY large video ram. The altera dev boards does not have that much RAM...
Any way, wait and see if someone else will give you more information.