Running on water

I recently viewed my topic about my project to find someone complimented it, and this gave me a new found inspiration to work on it again after I lost everything when my back up was erased. Anyways, I caught back up to where I was and am beginning to form ideas for level design and I was wondering is it possible to create a running on water effect, like in HCZ on S3/K, with the Sonic 1 physics engine?

 

You need to know, how to make objects solid. This is my beginning of "Obj01_InWater":



Obj01_InWater:
lea ($FFFFD000).w,a2 ; load sonic object into a2


move.w $10(a2),d2 ; load X-yelocity into d2


cmpi.b #$900,$10(a2) ; is sonic fast enough to run on the water?


blt.s ChkWater_cont ; if not, branch


jsr SolidObject ; make water object solid


ChkWater_cont:



I'm not sure, how to make objects solid, so I just tried this. Mabe you'll have more luck.

 

Well, I wasn't actually looking for code (mainly because it's all gibberish to me at the moment), and while I don't understand any of the code you posted, you did actually answer my question. I just wanted to make sure I didn't have to use a different physics engine.


I'm not actually going to use that code because I don't understand it (and I'll be damned if I put something I don't understand into my work) but thanks anyways.

 

Just for the lulz, you only need to check if Sonic is fast enough and have to make the water solid. This is everything, even though I don't know how to do it.

 

Thanks, I was just wanting to know if it was possible. If I decide to use it, I'm sure I'll figure it out eventually.

 

Well, if you have enough knowledge, you can do EVERYTHING with ASM. =P

 

Obj01_InWater:
lea ($FFFFD000).w,a2 ; load sonic object into a2


move.w $10(a2),d2 ; load X-yelocity into d2


cmpi.b #$900,$10(a2) ; is sonic fast enough to run on the water?


blt.s ChkWater_cont ; if not, branch


jsr SolidObject ; make water object solid


ChkWater_cont:



Basically, it puts the Sonic object into a2. Now, in the next line, we take Sonic's x-velocity from a2 and put it into d2. Then it compares his speed to $900 (it seems). If it is not, then it branches to the normal water code. If it is greater than $900, it skips that line and makes the water solid (although that code does not exist).


I'm not the most knowledgeable person when it comes ASM, but I can write good pseudo code (read "code in plain words").

 

That's pretty easy to understand, but what purpose does moving the x-velocity to D2 and comparing it to $900 serve?

 

O_O; Uhh sorry, this line was actually completly unnecesary...

Sonic's velocity is stored in $10(a0). $900 is Sonic, when he is running very fast. We need to check his speed, or Sonic could also stand on the water. =P

 

Ok that makes sense.


This is the part about ASM that defeats me. I understand the commands and what they do, but I don't understand the syntax at all. How do you know what all these different values actually mean?

 

Because I'm awesome. *runs*


No srs, I just have a freaking wierd brain. I can remeber lots of things, even if I don't want. After my second ban, I learned as much as possible. And suddendly I could work with ASM. It's like, I got this ability over night. After that I was looking at this to learn some stuff by hard. But I learned the most stuff by creating stuffs like Jumpdash and Peelout.

 

I wondered why you never referred to d2 anywhere. :\