Jules Richardson wrote:
On Tue, 2005-07-26 at 16:53 -0400, Jeff Davis wrote:
I was just setting up Tera Term Pro on my windows
box (talk about overkill -
1.4Ghz and 768MB to run an ascii terminal!)
with that sort of speed you could probably emulate the CRT of the
original terminal itself, with all the gaps between lines and the light
fall-off around each pixel :-)
Jules,
It is funny you should mention it. My recently released Wang 2200 emulator does
exactly that when you configure it to use the true bitmap font (vs. a system
native font) for rendering the display.
Luckily the active part of the character cell is surrounded by enough inactive
padding pixels that I can carry out the blurring convolution and store it in the
character bit map and then just blit these preconvolved character images to the
display. This is less than perfect in two ways: first, this is only true for
filter kernels of 3x3 or less. Second, the cursor underbar is as wide as the
character cell (not just the active part) so they should affect adjacent
character cells. I just ignore that little problem.
The emulator also has realtime brightness and contrast controls. I thought
about adding a focus knob as well, which would modify the filter kernel, but I
decided to keep things simple for now.
If you want to see what it looks like (emulated vs real), click these links (4KB
and 93KB respectively):
http://home.pacbell.net/frustum/wang_emuscreen.gif
http://home.pacbell.net/frustum/wang_realscreen.jpg
Look at the cursor on the emulated screen and you will see that it isn't
blurred. It could be fixed without any noticable speed hit, but it would take
time to code it up and I have more significant things I'd rather work on.
Finally, earlier in development when I had added the bit accurate font map, it
was painful to look at the screen. The blur really made it much easier to read.