slederer/Tridora-CPU
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages 3 Wiki Activity Actions

vgafb: simplify maskgen a bit to avoid timing problems

Browse source
This commit is contained in:
slederer 2026-02-01 22:08:06 +01:00
parent bf813fac1d
commit f90d52926f
4 changed files with 33 additions and 37 deletions
Download patch file Download diff file Expand all files Collapse all files

3
examples/sprites.s
View file

@ -97,6 +97,7 @@ PS_LOOP1:
STORE.B FB_SHIFTCOUNT
LOAD.B FB_SHIFTERM ; get shifted mask
NOT
LOAD.B FB_IO ; and background pixel data
AND ; remove foreground pixels
@ -130,6 +131,7 @@ PS_NEXT_STRIPE:
STORE.B FB_MASKGEN ; store to mask reg to get new mask
LOAD.B FB_MASKGEN ; get mask for spill bits + shifted pixels
NOT
LOAD.B FB_IO ; get vmem data
AND ; remove foreground pixels from bg
@ -147,6 +149,7 @@ PS_NEXT_STRIPE:
DUP
STORE.B FB_MASKGEN
LOAD.B FB_MASKGEN ; get sprite mask for spill bits
NOT
LOAD.B FB_IO ; load next vmem word
AND ; apply sprite mask