User talk:Zowayix

Re: Stadium critical hit calculation?

I'm still a beginner at N64 MISP, but the formula given at the beginning is 100% correct, even if my comments are lackluster at the moment to say the least. Also please forgive my bad English =P

What happens is:

• Base Speed is loaded to V1
• It adds 76 to it
• It >> 2 to it
• It jumps to 0x35C56C
• It loads Focus Energy in T1
• If Focus Energy is active, value << 2
• If Focus Energy is active, value + 160
• If Focus Energy is not active, value << 1
• It loads Move ID in A0
• It jumps to 0x35A614
• It checks if the Move is a High Critical Hit Rate move. It compares the Move ID with the array at 0x37570C
• It jumps to 0x35C5A4
• It loads the CH Ratio to V1
• If the move is a High Critical Hit Rate move, << 2 to it
• If the move is not a High Critical Hit Rate move, >> 1 to it

I didn't check what happens just after this. I used access breakpoints and register breakpoints to find the routines that I wanted to explore.

• It jumps to 0x35C5FC
• If the CH Ratio is ≥ 256, it sets the CH Ratio to 255

I didn't check what happens just after this once again.

• It jumps to 0x35C648
• It loads the CH Ratio in V1
• It copies a 1-byte Pseudo-Random Number to T5
• If PRN < CH Ratio, it sets the Critical Hit flag to 1
• It jumps to 0x35A9C0, which is the start of the Damage Calculation

That gives us:

No Focus Energy: (Base Speed + 76) >> 2
W/ Focus Energy: (Base Speed + 76) >> 2 << 2 + 160 >> 1

Once again I apologize for the lack of clarity in the disassembly, as I'm copy pasting what I find on the go. I hope I didn't miss a shift operation while writing this!
Also, feel free to edit the ROM map to make it more easy to understand, I'm far from being the best at assembly :q
--Mantidactyle (talk) 18:36, 8 January 2015 (EST)