Move graphics origin to bottom left.

2024-06-13 07:29:35 +00:00 · 2021-09-21 17:30:31 -04:00 · 2021-09-21 17:30:31 -04:00 · c8e4940913
commit c8e4940913
parent a485abfc77
3 changed files with 7 additions and 4 deletions
--- a/applecorn.po
+++ b/applecorn.po
--- a/auxmem.gfx.s
+++ b/auxmem.gfx.s
@ -57,9 +57,11 @@ CVTCOORD
            LSR   A
            ROR   ZP2+0
            LSR   A
-            STA   VDUQ+8        ; ZP2 -> Y-coord
-            LDA   ZP2+0
-            ROR
+            ROR   ZP2+0
+            STZ   VDUQ+8        ; MSB always zero
+            SEC
+            LDA   #191          ; 191 - ZP2 -> Y-coord
+            SBC   ZP2+0
            STA   VDUQ+7
            RTS

--- a/auxmem.vdu.s
+++ b/auxmem.vdu.s
@ -585,7 +585,8 @@ VDU16        >>>   XF2MAIN,CLRHGR
 VDU16RET     >>>   ENTAUX
             STZ   XPIXEL+0
             STZ   XPIXEL+1
-             STZ   YPIXEL
+             LDA   #191
+             STA   YPIXEL
             RTS

 * VDU 17 - COLOUR n - select text or border colour