While just the first episode has been released, The iBook Guy is creating a series of videos that explains the limitations of “oldschool” graphics. When you have just a handful of kilobytes of RAM, it is impossible to even store a full-quality frame buffer that the TV requires, which means that something will need to be thrown away.
The first video talks about adding color to frames with tiling and sprites. Using just ~1K of RAM, software developers were able to define background colors on a tile-by-tile basis. This allowed “black and white” to be an arbitrary “foreground and background” combination, which could even vary from one tile to the next as long as each tile only used two colors. This concept is expanded on to allow four colors per tile at a slight reduction in resolution. The video then goes into sprites, and how they are used for movable actors atop the tiles.
Image Credit: The iBook Guy
I don't know when Part 2 will be published, but it seems like they release about once per week.
very cool video
very cool video
PEEK and POKE, I used them a
PEEK and POKE, I used them a lot on the Trash-80’s, no sprites on the model 3, but lots of ASCII fun on the screen and other memory mapped fun. Great Video by the iBook GUY can’t wait for more history lessons.
I had build my own painting
I had build my own painting program back in the spectrum days. With no internet available, you had to be creative back then.
The idea behind that program for painting a whole 256X192 picture, wasn’t much different than the way he created the pacman sprite in the above video. Using the symbols than Spectrum was offering(keys 0-9) and the joystick for moving around, I was creating piece by piece(64X48 pixels) the screen like a puzzle. The work was taking place in a zooming window(4X zoom) and then pasting the final result in the correct coordinates. Nice old days.
“Raster? W-w-what is that?”
“Raster? W-w-what is that?” (c) you-know-who
Hopefully the effect of the
Hopefully the effect of the use of CRT displays on colour output (and on interlaced/noninterlaced field output) will be mentioned too. the effects go WELL beyond the commonly seen ‘scanline’ effects. There are some nifty chroma shift effects that rely on subpixel blooming, as do some tricks used on consoles (e.g. the ‘pseudo-hires transparency’ on the SNES). The fringe colour blending combine with the bright sharp central ‘luma’ highlight also had an effect on how ‘pixel art’ is perceived (kind of like a Ghetto 4:2:0 subsampling).
These effects are absent on an LCD without using a shader that simulates a CRT, so may be missed if you have never seen a CRT driven at lower resolutions (or haven’t seen one for a while).
It was all pointillism with
It was all pointillism with Pixels in those days, but now things are much more complex.
here is an interesting article from 1999, and I can only guess at how many advancements have been made and implemented since then.
http://www.americanscientist.org/issues/pub/seeing-between-the-pixels
The second episode is up now.
The second episode is up now.
the effects go WELL beyond
the effects go WELL beyond the commonly seen ‘scanline’ effects. There are some nifty chroma shift effects that rely on subpixel blooming http://obatflekparuparu1.blogspot.com