-----Original Message-----
From: Eckhard Stolberg <Eckhard_Stolberg@xxxxxxxxxxxxxxxxxxxxx>
>I have tried your experiment and can confirm your results, except
>that I get only two copies at Hit5. This might be the same
>incompatibility as with the trick18 program. What version of the
>VCS are you using?
Mostly, a classic VCS with a Rev-9 board. How about you? (I'm really
hoping it's an Atari JR, that would explain a lot...)
>
>Can all of you please try out the enclosed 2or3.bin on a real VCS
>and tell us if you see 2 or 3 sprites and which VCS modell you are
>using?
When I try this on my classic VCS, I see three sprites. I also tried a
different TIA chip from a Rev-16 VCS and I also see three sprites. When
I try an Atari JR I see two sprites.
>
>I also did the same experiment with a NUSIZ value of 6 (3 copies
medium)
>and got 3 copies for the second hit at cycle 11 and 22. So in both
>experiments I got 3 copies when I hit RESPx 4 or 3 pixels before the
>next sprite of the first set would be displayed. One cycle later,
>which is 1 or 0 pixel before the next sprite of the first set, I
>got only 2 copies. Maybe I need to revise my 5 pixel delay theory
>again. ;-)
Well, I'm attaching ALL of my data (hits.txt). I found that there are
different results for both (d+3) positioning and (d-1) positioning
between classic VCS and Atari JR. I've also redrawn the sprite map
(collide.txt) and I'm attaching it too. I guess what's interesting if
you look at the results for missiles, and combine the cases of when the
classic VCS and the Atari JR give three sprites, it matches your five
pixel delay theory perfectly. :-)
John
This data taken with Rev 9 VCS
==============================
Players -- three copies close
-----------------------------
Hit3 9 , 25 , 41 -- 18 , 34*, 50* (d-7)
Hit4 9 , 25 , 41 -- 21 , 37*, 53* (d-4)
Hit5 9 , 25 , 41 -- 24*, 40*, 56* (d-1)*
Hit6 9 , 25 , 41 -- 27*, 43*, 59* (d+2)*
Hit7 9 , 25*, 41 -- 30 , 46*, 52* (d+5)
Hit8 9 , 25*, 41 -- 33 , 49*, 65* (d-8)
Hit9 9 , 25*, 41 -- 36 , 52*, 68* (d-5)
Hit10 9 , 25*, 41 -- 39 , 55*, 71* (d-2)
Hit11 9 , 25*, 41 -- 42*, 58*, 74* (d+1)*
Hit12 9 , 25*, 41* -- 45 , 61*, 77* (d+4)
Players -- three copies medium
------------------------------
MPHit10 9 , 41 , 73 -- 39 , 71* , 103* (d-2)
MPHit11 9 , 41 , 73 -- 42*, 74* , 106* (d+1)*
MPHit12 9 , 41*, 73 -- 45 , 77* , 109* (d+4)
MPHit20 9 , 41*, 73 -- 69 , 101*, 133 (d-4)
MPHit21 9 , 41*, 73 -- 72*, 104*, 136* (d-1)*
MPHit22 9 , 41*, 73 -- 75*, 107*, 139* (d+2)
MPHit23 9 , 41*, 73* -- 78 , 110*, 142* (d+5)
MPHit30 9 , 41*, 73* -- 99 , 131*, 163(3)* (d+6)
MPHit31 9 , 41*, 73* -- 102, 134*, 166(6)* (d+3)
MPHit32 9*, 41*, 73* -- 105, 137*, 169(9) (d+0)*
MPHit33 9 , 41*, 73* -- 108, 140*, 172(12) (d-3)
Missiles -- three copies close
------------------------------
MHit3 8 , 24 , 40 -- 17 , 33*, 49* (d-7)
MHit4 8 , 24 , 40 -- 20 , 36*, 52* (d-4)
MHit5 8 , 24 , 40 -- 23*, 39*, 55* (d-1)*
MHit6 8 , 24 , 40 -- 26*, 42*, 58* (d+2)*
MHit7 8 , 24*, 40 -- 29 , 45*, 61* (d+5)
MHit8 8 , 24*, 40 -- 32 , 48*, 64* (d-8)
MHit9 8 , 24*, 40 -- 35 , 51*, 67* (d-5)
MHit10 8 , 24*, 40 -- 38 , 54*, 70* (d-2)
MHit11 8 , 24*, 40 -- 41*, 57*, 73* (d+1)*
MHit12 8 , 24*, 40* -- 44 , 60*, 76* (d+4)
MHit40 8 , 24*, 40* -- 128, 144*, 160(0)* (d+8)
MHit41 8 , 24*, 40* -- 131, 147*, 163(3)* (d+5)
MHit42 8*, 24*, 40* -- 134, 150*, 166(6) (d+2)*
MHit43 8*, 24*, 40* -- 137, 153*, 169(9) (d-1)*
MHit44 8 , 24*, 40* -- 140, 156*, 172(12) (d-4)
Missiles -- three copies medium
-------------------------------
MMHit10 8 , 40 , 72 -- 38 , 70* , 102* (d-2)
MMHit11 8 , 40 , 72 -- 41*, 73* , 105* (d+1)*
MMHit12 8 , 40*, 72 -- 44 , 76* , 108* (d+4)
MMHit20 8 , 40*, 72 -- 68 , 100*, 132* (d-4)
MMHit21 8 , 40*, 72 -- 71*, 103*, 135* (d-1)*
MMHit22 8 , 40*, 72 -- 74*, 106*, 135* (d+2)*
MMHit23 8 , 40*, 72* -- 77 , 109*, 138* (d+5)
MMHit30 8 , 40*, 72* -- 98 , 130*, 162(2)* (d+6)
MMHit31 8 , 40*, 72* -- 101, 133*, 165(5) (d+3)
MMHit32 8*, 40*, 72* -- 104, 136*, 168(8) (d+0)*
MMHit33 8 , 40*, 72* -- 107, 140*, 171(11) (d-3)
This data taken with Atari JR
=============================
Hit5 9 , 25 , 41 -- 24 , 40* , 56* (d-1)
MPHit21 9 , 41*, 73 -- 72 , 104*, 136* (d-1)
MPHit31 9*, 41*, 73* -- 102, 134*, 166(6) (d+3)*
MHit5 8 , 24 , 40 -- 23 , 39* , 55* (d-1)
MHit43 8 , 24*, 40* -- 137, 153*, 169(9) (d-1)
MMHit31 8*, 40*, 72* -- 101, 133*, 165(5) (d+3)*
Note: When I rerun the tests I ran on the Atari JR on a different TIA chip
from a Rev-16 board, installed in my Rev-9 board, I get the same
results as the original Rev-9 TIA chip.
When Sprites Collide (revised Jan 14, 1999)
===========================================
-------- = invisible sprite
ssssssss = sprite seen on Classic VCS and Atari JR
cccccccc = sprite seen only on Classic VCS
jjjjjjjj = sprite seen only on Atari JR
Missiles
========
(d+4)
--------........ssssssss........ssssssss
^ --------........ssssssss........ssssssss
(d+3)
--------........ssssssss........--------
^ jjjjjjjj........ssssssss........ssssssss
(d+2)
--------........ssssssss........--------
^ ssssssss........ssssssss........ssssssss
(d+1)
--------........ssssssss........--------
^ ssssssss........ssssssss........ssssssss
(d+0)
--------........ssssssss........--------
^ ssssssss........ssssssss........ssssssss
(d-1)
--------........ssssssss........--------
^ cccccccc........ssssssss........ssssssss
(d-2)
--------........ssssssss........--------
^ --------........ssssssss........ssssssss
Players
=======
On Classic VCS only (d+3) positioning is different between missiles and players.
On Atari JR missiles and players work the same.
(d+4)
--------........ssssssss........ssssssss
^ --------........ssssssss........ssssssss
(d+3)
--------........ssssssss........cccccccc
^ jjjjjjjj........ssssssss........ssssssss
(d+2)
--------........ssssssss........--------
^ ssssssss........ssssssss........ssssssss
(d+1)
--------........ssssssss........--------
^ ssssssss........ssssssss........ssssssss
(d+0)
--------........ssssssss........--------
^ ssssssss........ssssssss........ssssssss
(d-1)
--------........ssssssss........--------
^ cccccccc........ssssssss........ssssssss
(d-2)
--------........ssssssss........--------
^ --------........ssssssss........ssssssss
