How to put the mask bitplane behind the other bitplanes??

method · 13 February 2006, 14:29

On a few games (Rainbow Islands, New Zealand Story, etc.) - I've found that the fifth bitplane is often the mask.

Disabling this bitplane allows sprites to appear normal as long as they're on a black background.

Without disabling it, the black mask is drawn over the top of the other bitplanes obscuring the sprites almost completely.

What I'd like to know is if there is an easy way to make the 5th bitplane (the mask) appear under the others rather than over it.

I've tried reversing the bitplane order but that didn't work.

Anyone know??

If I could figure that out, I could rip more sprites with the purple background and black outlines, making them much more usable.

Photon · 13 February 2006, 16:58

Eh...?

Joe Maroni · 13 February 2006, 17:16

i don´t really know what you mean...

could you please post a picture ? maybe you just have to play with the skip function..

instead of 5 bitplane, use 4 and skip the last plane...

method · 13 February 2006, 18:49

Okay... here's a step by step...

method · 13 February 2006, 19:11

I can overlap the first four bitplanes over the fifth (mask) manually... but it's not the smartest solution...

cebulba · 14 February 2006, 23:50

Would you be able to write a complete tutorial with some examples on how to rip sprites? for the webpage (whoever will host it in the end

).

That would be great.

method · 15 February 2006, 02:53

I'll work on one soon (just gotta find the time!!!)... if it's any help though here's some rough tips for how I usually find the sprites... (just 'til I can write that guide/tutorial)

----

The order in which I usually do things:

1. Locate sprite in 2-colors (one bitplane) (we all know that already though.. yeah?!)
2. Assess whether sprite is AM or ST (I do this staying within the AM mode).

If it looks the correct size and the bitplane width is the same as the sprite width... it's AM.
If it looks the correct size but the bitplane width is larger, it's ST.

The difference is, with AM, bitplanes are laid out vertically.
With ST it's usually a horizontal strip, with each plane next to the other.

3a. If it's AM...
Reduce the bitplane height so that it matches sprite height exactly.
Then increase the bitplanes.

3b. If it's ST...
Reduce the bitplane width by the number of bitplanes you can see.
Then switch to ST mode
And then increase the number of bitplanes to that same number.

4. Once you've found the sprite, hunt through the palettes.
(If it's not the default, it's often one of the first couple of palettes found in "S" palette search.

5. Removing mask layers...

If the sprite looks correct but you cannot find the palette, try changing the order to:

76553210 (for 4 bitplanes excluding 5th mask bitplane)
or
76555210 (for 3 bitplanes excluding 4th mask bitplane)

(Without this you can't get the sprites from Rainbow Islands, Newzealand Story and loads of other games!!)

------------

ST mode sprites are generally the quickest to rip and you can often do them in segments.
AM mode sprite-SHEETS (320px*200px bitplanes) are ridiculously quick to rip.
AM mode single sprites can take longer as you often have to adjust the height of the bitplane.. for each and every sprite!!

YEAH... DEFINETELY needs pictures to make sense for most people. I've read through this pretending not to know the differences.. and I'd be confused.

13 February 2006, 14:29	#1
method Zone Friend Join Date: Feb 2006 Location: UK Age: 43 Posts: 94	How to put the mask bitplane behind the other bitplanes?? On a few games (Rainbow Islands, New Zealand Story, etc.) - I've found that the fifth bitplane is often the mask. Disabling this bitplane allows sprites to appear normal as long as they're on a black background. Without disabling it, the black mask is drawn over the top of the other bitplanes obscuring the sprites almost completely. What I'd like to know is if there is an easy way to make the 5th bitplane (the mask) appear under the others rather than over it. I've tried reversing the bitplane order but that didn't work. Anyone know?? If I could figure that out, I could rip more sprites with the purple background and black outlines, making them much more usable.

13 February 2006, 18:49	#4
method Zone Friend Join Date: Feb 2006 Location: UK Age: 43 Posts: 94	Okay... here's a step by step... Attached Thumbnails

13 February 2006, 19:11	#5
method Zone Friend Join Date: Feb 2006 Location: UK Age: 43 Posts: 94	I can overlap the first four bitplanes over the fifth (mask) manually... but it's not the smartest solution... Attached Thumbnails

15 February 2006, 02:53	#7
method Zone Friend Join Date: Feb 2006 Location: UK Age: 43 Posts: 94	I'll work on one soon (just gotta find the time!!!)... if it's any help though here's some rough tips for how I usually find the sprites... (just 'til I can write that guide/tutorial) ---- The order in which I usually do things: 1. Locate sprite in 2-colors (one bitplane) (we all know that already though.. yeah?!) 2. Assess whether sprite is AM or ST (I do this staying within the AM mode). If it looks the correct size and the bitplane width is the same as the sprite width... it's AM. If it looks the correct size but the bitplane width is larger, it's ST. The difference is, with AM, bitplanes are laid out vertically. With ST it's usually a horizontal strip, with each plane next to the other. 3a. If it's AM... Reduce the bitplane height so that it matches sprite height exactly. Then increase the bitplanes. 3b. If it's ST... Reduce the bitplane width by the number of bitplanes you can see. Then switch to ST mode And then increase the number of bitplanes to that same number. 4. Once you've found the sprite, hunt through the palettes. (If it's not the default, it's often one of the first couple of palettes found in "S" palette search. 5. Removing mask layers... If the sprite looks correct but you cannot find the palette, try changing the order to: 76553210 (for 4 bitplanes excluding 5th mask bitplane) or 76555210 (for 3 bitplanes excluding 4th mask bitplane) (Without this you can't get the sprites from Rainbow Islands, Newzealand Story and loads of other games!!) ------------ ST mode sprites are generally the quickest to rip and you can often do them in segments. AM mode sprite-SHEETS (320px200px bitplanes) are ridiculously quick to rip. AM mode single sprites can take longer as you often have to adjust the height of the bitplane.. for each and every sprite!! YEAH... DEFINETELY needs pictures to make sense for most people. I've read through this pretending not to know the differences.. and I'd be confused. Last edited by method; 15 February 2006 at 14:22.*

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13 February 2006, 16:58	#2
Photon Moderator Join Date: Nov 2004 Location: Eksjö / Sweden Posts: 5,604	Eh...?

13 February 2006, 17:16	#3
Joe Maroni Moderator Join Date: Feb 2003 Location: Germany Age: 44 Posts: 1,303	i don´t really know what you mean... could you please post a picture ? maybe you just have to play with the skip function.. instead of 5 bitplane, use 4 and skip the last plane...

14 February 2006, 23:50	#6
cebulba Junior Member Join Date: Oct 2003 Location: Schneiderkrug/Germany Age: 47 Posts: 251	Would you be able to write a complete tutorial with some examples on how to rip sprites? for the webpage (whoever will host it in the end ). That would be great.

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