It can be found in the src/sp1-partial-inv-1 directory. Based on Test 2, but this one keeps track of the tiles that are present on each column, and only invalidates the cells that are affected by them. It also keeps track of how the tiles walk down the screen, and propery moves the cells to invalidate.

It can be found in the src/sp1-sprites directory. It’s the previous Test 1 real scroller, but this time with sprites running all over the place, while the background is scrolling down.

It can be found in the src/sp1-randomtiles directory. This is a real scrol|ler, using the workflow that would be used for a real game: tiles are drawn on some non-visible top rows and are brought into view by the scrolling process. In this example, the logic for printing tiles on the top is trivial, but in a real game those would come from a map.

(This is the first in a series of articles about developing scrolling games on the ZX Spectrum using Z88DK toolchain and the SP1 Sprite Library by Alvin Albrecht. All mentioned code and also draft versions of these articles can be found at the GitHub repo )

Hey friends: I have released RAGE1 0.5.0 after more than a year of development, with loads of new features, such as 128K music with integrated Arkos2 tracker, automatic map generation and many gameplay improvements.