How "oldschool" graphics worked

[vwalbridge]

This video just popped up on my radar today. For many of you enthusiasts, you probably already knew this. But for me, it was a really informative video showing how graphics were created in the early days. I now have even more respect for early game designers.

http://www.youtube.com/watch?t=310&v=Tfh0ytz8S0k

[ark_ader]

I made some games up and shared them with friends at school.  The C64 was the best, and you hack a game together really quickly.  The BBC micro introduced me to assembler and well the rest is History.  Nice series.  I cringed at the graph paper though. 

[Xiaou2]

Im not sure about the accuracy here...

 The term "Color Cell"  is not really the standard term.

 Generally, the background graphics use what are called "Tiles".

 On the C64, these tiles were often the same very shape as the letters that you saw when you typed.  I think it was an 8 x 8  grid.

 If you look at a C64 keyboard,  you will notice some odd graphical shapes on the front face of the letter keys.   Using a two key combination, you could make these shapes appear, instead of letters.

 In this way... you could draw an entire screen of what is basically (alternated) Letter Tiles,  to form a picture.   This takes up far less memory, because you would re-use tiles in various parts of your drawing.

 Instead of using text style blocky movement however... I believe the c64 had a hardware method of scrolling at a per pixel mode.  Once it moved a full tile from the boarder... you would draw the new tile to be displayed.    I cant recall, but it might have just scrolled the data inside the tile..    its been a long time.

 I made sprites frequently on the C64.    And I used the built in C64 character set for the background.   However, I later learned that you would need a character-set editor,  to redefine all of your keys graphics... to get a decently good looking effect.

 I wasnt aware of limitations on character set color limits.   I guess it makes sense... I just never got that far..   and I dont think it was mentioned in the included manuals.

 I also didnt recall anything about lower resolutions.


 Anyways... Tilesets are used just as much in todays games as they were in the past.   They are not locked into your Text engine, like the C64 though.    And there is far less concern for memory and color limitations.   Still... on heavy CPU intensive operations, even modern systems can struggle... if the resolution is very high, and the graphical details are taking up a lot of memory.  Not quite the same... but think about Photoshop.. and the time it can take to render an effect.   

 As such... many games still may limit the number of objects on screen,  and the detail levels.. to provide faster gameplay / draw speed.  For example... on an OutRun style game... where speed of the road is very critical in the enjoyment of the gameplay.

[pbj]

Didn't the C64 have some ridiculously low sprite limit?  I took some 'game programming class' circa 1995 and we used some graphics program to create sprites for games we were programming.  Seemed like it went tits up if you had more than 8 objects on the screen.

[Xiaou2]

Didn't the C64 have some ridiculously low sprite limit?  I took some 'game programming class' circa 1995 and we used some graphics program to create sprites for games we were programming.  Seemed like it went tits up if you had more than 8 objects on the screen.

Ahh, found the answer to a few more things:

http://gamedev.stackexchange.com/questions/22037/what-exactly-makes-up-a-screen-in-a-typical-c64-game

[vwalbridge]

And here is part 2:

http://www.youtube.com/watch?t=16&v=_rsycfDliZU

[RayB]

Im not sure about the accuracy here...

 The term "Color Cell"  is not really the standard term.

 Generally, the background graphics use what are called "Tiles".

 On the C64, these tiles were often the same very shape as the letters that you saw when you typed.  I think it was an 8 x 8  grid.

 If you look at a C64 keyboard,  you will notice some odd graphical shapes on the front face of the letter keys.   Using a two key combination, you could make these shapes appear, instead of letters.

 In this way... you could draw an entire screen of what is basically (alternated) Letter Tiles,  to form a picture.   This takes up far less memory, because you would re-use tiles in various parts of your drawing.

 Instead of using text style blocky movement however... I believe the c64 had a hardware method of scrolling at a per pixel mode.  Once it moved a full tile from the boarder... you would draw the new tile to be displayed.    I cant recall, but it might have just scrolled the data inside the tile..    its been a long time.

 I made sprites frequently on the C64.    And I used the built in C64 character set for the background.   However, I later learned that you would need a character-set editor,  to redefine all of your keys graphics... to get a decently good looking effect.

 I wasnt aware of limitations on character set color limits.   I guess it makes sense... I just never got that far..   and I dont think it was mentioned in the included manuals.

 I also didnt recall anything about lower resolutions.


 Anyways... Tilesets are used just as much in todays games as they were in the past.   They are not locked into your Text engine, like the C64 though.    And there is far less concern for memory and color limitations.   Still... on heavy CPU intensive operations, even modern systems can struggle... if the resolution is very high, and the graphical details are taking up a lot of memory.  Not quite the same... but think about Photoshop.. and the time it can take to render an effect.   

 As such... many games still may limit the number of objects on screen,  and the detail levels.. to provide faster gameplay / draw speed.  For example... on an OutRun style game... where speed of the road is very critical in the enjoyment of the gameplay.

There definitely was a concept called a cell, and there was also a bitmap mode. What you're talking about is the character mode.

Read all about it here. This book was THE bible we all used to learn everything about every feature and even EVERY memory location in the C64:  http://www.commodore.ca/manuals/c64_programmers_reference/c64-programmers_reference.htm

[eds1275]

Oh man I remember that book.