Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Add some comments about the tkmk00 stuff #594

Open
wants to merge 1 commit into
base: master
Choose a base branch
from
Open

Add some comments about the tkmk00 stuff #594

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
20 changes: 20 additions & 0 deletions asm/tkmk00_decode.s
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -10,6 +10,20 @@

.section .text, "ax"

/*
See these links for potential references to implement our own TKMK00 (de)compression code
https://github.com/mib-f8sm9c/MiscellaneousHacks/blob/master/BetaTools/MarioKartTestingTool/TKMK00Encoder.cs
https://skelux.net/showthread.php?tid=47&page=8

This link appears to have code near identical to libtkmk000
https://github.com/mib-f8sm9c/MiscellaneousHacks/blob/master/BetaTools/MarioKartTestingTool/TKMKTest.cs
Did libtkmk00 pull from that link, or vice-versa?

Maybe tkmk00 wasn't compiled with IDO. Its explicit usage of registers rather than variables is something that IDO can't do (I think?) but GCC can.
Or mabybe its C++ code and that interacts with registers differently?
Or maybe its all hand written?
Copy link
Collaborator

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

It's my understanding that this assembly was hand-written.

Copy link

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

It is if you know where to look.

Copy link
Collaborator

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

The code was likely assembled using IDO, however the code is almost certainly hand-written given the bal, add, and sub, instructions which are not used by any known compiler.

*/

glabel tkmk00decode
/* 0411D0 800405D0 23BDFC00 */ addi $sp, $sp, -0x400
/* 0411D4 800405D4 AFB0019C */ sw $s0, 0x19c($sp)
Expand Down Expand Up @@ -342,6 +356,7 @@ glabel tkmk00decode
/* 041658 80040A58 03E00008 */ jr $ra
/* 04165C 80040A5C 23BD0400 */ addi $sp, $sp, 0x400

# func_80040A60 -> masterReader.ReadBits
glabel func_80040A60
/* 041660 80040A60 00E3C820 */ add $t9, $a3, $v1
/* 041664 80040A64 24180020 */ li $t8, 32
Expand Down Expand Up @@ -374,6 +389,7 @@ glabel func_80040A60
/* 0416C0 80040AC0 03E00008 */ jr $ra
/* 0416C4 80040AC4 00E84004 */ sllv $t0, $t0, $a3

# func_80040AC8 -> commandReader.ReadBits
glabel func_80040AC8
/* 0416C8 80040AC8 006AC006 */ srlv $t8, $t2, $v1
/* 0416CC 80040ACC 33190001 */ andi $t9, $t8, 1
Expand Down Expand Up @@ -445,6 +461,7 @@ glabel func_80040AC8
/* 0417B8 80040BB8 03E00008 */ jr $ra
/* 0417BC 80040BBC 00000000 */ nop

# func_80040BC0 -> SetUpHuffmanTree
Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

why not rename it ?

glabel func_80040BC0
/* 0417C0 80040BC0 AE7FFFF8 */ sw $ra, -8($s3)
/* 0417C4 80040BC4 2273FFF8 */ addi $s3, $s3, -8
Expand Down Expand Up @@ -487,6 +504,7 @@ glabel func_80040BC0
/* 04184C 80040C4C 03E00008 */ jr $ra
/* 041850 80040C50 00000000 */ nop

# func_80040C54 -> RetrieveHuffmanTreeValue
glabel func_80040C54
/* 041854 80040C54 0120A025 */ move $s4, $t1
/* 041858 80040C58 03E09825 */ move $s3, $ra
Expand All @@ -507,6 +525,8 @@ glabel func_80040C54
.L80040C8C:
/* 04188C 80040C8C 02600008 */ jr $s3
/* 041890 80040C90 00000000 */ nop

# func_80040C94 -> ColorCombine
glabel func_80040C94
/* 041894 80040C94 2B010010 */ slti $at, $t8, 0x10
/* 041898 80040C98 54200013 */ bnel $at, $zero, .L80040CE8
Expand Down
2 changes: 2 additions & 0 deletions tools/libtkmk00.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -127,6 +127,7 @@ void tkmk00_decode(uint8_t *tkmk, uint8_t *tmp_buf, uint8_t *rgba16, int32_t alp
}
}

// These are misnamed, this is the green prediction
red0 = (rgba0 & 0x7C0) >> 6;
red1 = (rgba1 & 0x7C0) >> 6;
t8 = (red0 + red1) / 2;
Expand All @@ -135,6 +136,7 @@ void tkmk00_decode(uint8_t *tkmk, uint8_t *tmp_buf, uint8_t *rgba16, int32_t alp
s0 = t9;

v1 = t9 - t8;
// These are misnamed, this is the red prediction
green0 = (rgba0 & 0xF800) >> 11;
green1 = (rgba1 & 0xF800) >> 11;
t8 = v1 + (green0 + green1) / 2;
Expand Down