Project Sonic 1: Two-Eight

Yes, that could work, though I would imagine you'd need more than one, as it's more of taking the X and Y positions of the level and manipulating them into reading the correct position of the layout data (which collects the chunk in question and reads from there, etc), and this will vary depending on the size of the level's data on X and Y axiz (should they be altered), and not just the size of the chunks in question.

I think he's referring to the chunk size which can be altered by changing a simple value (making it more easy to change at a programmer's will), and not SonED.

 

Sorry to bump and double post...

<!--quoteo(post=20026:date=Sunday 4th July 2010, 5:10 pm:name=OrdosAlpha)--><div class='quotetop'>QUOTE (OrdosAlpha @ Sunday 4th July 2010, 5:10 pm) </div><div class='quotemain'><!--quotec-->Looks like StephenUK and myself have discovered a flaw with this - it's not Rev 01 effect friendly. Which is lame, as the improved rasterization makes the zone BGs look better. Any chance you could look into this?[/QUOTE]
Ok found what's wrong, when porting the Rev effects, it ports not only the BG deformation but the draw code from the Rev version, and of course, this overwrites my modification of the 128x128 engine.

If you've ported the Rev effects to the Two-Eight engine, then you must follow these further steps to enable it to work correctly:

Code (Text):

1. ----------------------------------------------------
2. goto sub_6886:
3.  
4. change
5.  
6. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;lea&nbsp;&nbsp;&nbsp;&nbsp;($FFFFA440).w,a4
7.  
8. to
9.  
10. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;movea.l&nbsp;&nbsp;&nbsp;&nbsp;($FFFFA404).w,a4; MJ: Load address of layout BG
11.  
12. ----------------------------------------------------
13. goto LoadTilesAsYouMove:
14.  
15. change
16.  
17. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;lea&nbsp;&nbsp;&nbsp;&nbsp;($FFFFA440).w,a4
18.  
19. to
20.  
21. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;movea.l&nbsp;&nbsp;&nbsp;&nbsp;($FFFFA404).w,a4; MJ: Load address of layout BG
22.  
23. and change
24.  
25. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;lea&nbsp;&nbsp;&nbsp;&nbsp;($FFFFA400).w,a4
26.  
27. to
28.  
29. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;movea.l&nbsp;&nbsp;&nbsp;&nbsp;($FFFFA400).w,a4; MJ: Load address of layout
30.  
31. ----------------------------------------------------
32. goto sub_70AC:&nbsp;&nbsp;(Was sub_6B32: in normal S1)
33.  
34. change
35.  
36. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;btst&nbsp;&nbsp;&nbsp;&nbsp;#4,(a0)
37.  
38. to
39.  
40. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;btst&nbsp;&nbsp;&nbsp;&nbsp;#3,(a0)&nbsp;&nbsp;&nbsp;&nbsp;; MJ: checking bit 3 not 4 (Flip)
41.  
42. and change
43.  
44. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;btst&nbsp;&nbsp;&nbsp;&nbsp;#3,(a0)
45.  
46. to
47.  
48. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;btst&nbsp;&nbsp;&nbsp;&nbsp;#2,(a0)&nbsp;&nbsp;&nbsp;&nbsp;; MJ: checking bit 2 not 3 (Mirror)
49.  
50. ----------------------------------------------------
51. goto loc_70E8: (Was loc_6B6E: in normal S1)
52.  
53. change
54.  
55. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;btst&nbsp;&nbsp;&nbsp;&nbsp;#3,(a0)
56.  
57. to
58.  
59. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;btst&nbsp;&nbsp;&nbsp;&nbsp;#2,(a0) ; MJ: checking bit 2 not 3 (Mirror)
60.  
61.  
62.  
63. ----------------------------------------------------
64. goto loc_712C: (Was sub_6BD6: in normal S1)
65.  
66. remove
67.  
68. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;lsr.w&nbsp;&nbsp;&nbsp;&nbsp;#1,d3
69.  
70. change
71.  
72. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;andi.w&nbsp;&nbsp;&nbsp;&nbsp;#$380,d3
73.  
74. to
75.  
76. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;andi.w&nbsp;&nbsp;&nbsp;&nbsp;#$780,d3; MJ: get within 780 (Not 380) (E00 pixels (not 700)) in multiples of 80
77.  
78.  
79. and change
80.  
81. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;lsr.w&nbsp;&nbsp;&nbsp;&nbsp;#5,d0
82.  
83. to
84.  
85. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;lsr.w&nbsp;&nbsp;&nbsp;&nbsp;#4,d0&nbsp;&nbsp;&nbsp;&nbsp;; MJ: divide by 10 (Not 20)
86.  
87. under this command
88.  
89. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;andi.w&nbsp;&nbsp;&nbsp;&nbsp;#$7F,d0; ''
90.  
91. insert this
92.  
93. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;lsl.w&nbsp;&nbsp;&nbsp;&nbsp;#$01,d3&nbsp;&nbsp;&nbsp;&nbsp;; MJ: multiply by 2 (So it skips the BG)
94.  
95. remove these two
96.  
97. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;beq.s&nbsp;&nbsp;&nbsp;&nbsp;locret_7172
98. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;subq.b&nbsp;&nbsp;&nbsp;&nbsp;#1,d3
99.  
100. change
101.  
102. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;andi.w&nbsp;&nbsp;&nbsp;&nbsp;#$7F,d3; ''
103.  
104. to
105.  
106. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;andi.w&nbsp;&nbsp;&nbsp;&nbsp;#$FF,d3&nbsp;&nbsp;&nbsp;&nbsp;; MJ: keep within FF
107.  
108. under this command
109.  
110. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ror.w&nbsp;&nbsp;&nbsp;&nbsp;#7,d3
111.  
112. insert this
113.  
114. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ror.w&nbsp;&nbsp;&nbsp;&nbsp;#2,d3&nbsp;&nbsp;&nbsp;&nbsp;; MJ: ..plus an extra 2 (so it's within 80 bytes, not 200)
115.  
116. remove
117.  
118. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;add.w&nbsp;&nbsp;&nbsp;&nbsp;d4,d4
119.  
120. change these two
121.  
122. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;andi.w&nbsp;&nbsp;&nbsp;&nbsp;#$1E0,d4
123. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;andi.w&nbsp;&nbsp;&nbsp;&nbsp;#$1E,d5
124.  
125. to this
126.  
127. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;andi.w&nbsp;&nbsp;&nbsp;&nbsp;#$070,d4; MJ: keep Y pos within 80 pixels
128. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;andi.w&nbsp;&nbsp;&nbsp;&nbsp;#$0E,d5&nbsp;&nbsp;&nbsp;&nbsp;; MJ: keep X pos within 10
129.  
130. ----------------------------------------------------
131. goto LoadTilesFromStart:
132.  
133. change
134.  
135. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;lea&nbsp;&nbsp;&nbsp;&nbsp;($FFFFA400).w,a4
136.  
137. to
138.  
139. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;movea.l&nbsp;&nbsp;&nbsp;&nbsp;($FFFFA400).w,a4; MJ: Load address of layout
140.  
141. and change
142.  
143. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;lea&nbsp;&nbsp;&nbsp;&nbsp;($FFFFA440).w,a4
144.  
145. to
146.  
147. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;movea.l&nbsp;&nbsp;&nbsp;&nbsp;($FFFFA404).w,a4; MJ: Load address of layout BG

You don't have to have the "; MJ:" comments in there, but it is suggested that you do, so you can at least remember where the changes were to be made, for the record I will provide a disassembly here of the Two-Eight engine with the rev effects, thanks for the bug report, much appreciated.