The status of ZDoom 2.0.97

Post by **Graf Zahl** » Mon Mar 21, 2005 3:14 am

rpeter wrote:Optimizing for speed is not just the compiler's territory. Ken used precalculated tables for almost everything: power, sqrt, sin, cosin, angles. Some were static tables in the code, the bigger ones were loaded from the grp file. Sure, you won't find many floats in Build, probably none in the Duke's game code, but with a fixed precision float lookup tables can also be created.

That was 10 years ago when computers were significantly slower than today. When you are using floats it is most likely fastest to use the CPU's sin, cos, sqrt commands and others. Tables only make sense if it is faster to calculate the index into the table than the needed value itself.

I still cannot imagine that those bird-brain piggies could be fitted with an AI that can slow down ZDoom noticably...

That depends on the amount you have in a level. Even though the AI doesn't cost much in overall percentage of execution time large amounts of monsters can still have an impact.

David Ferstat · Post by **David Ferstat** » Mon Mar 21, 2005 4:14 am

Anyone remember Cyb's "Helm's Deep"?

Post by **Graf Zahl** » Mon Mar 21, 2005 4:43 am

But that was due to drawing all the sprites, not the AI.

MartinHowe · Post by **MartinHowe** » Mon Mar 21, 2005 4:52 am

rpeter wrote:Optimizing for speed is not just the compiler's territory. Ken used precalculated tables for almost everything: power, sqrt, sin, cosin, angles.

Spooky! I was up late last night trying to get wad2map to work with JonoF's stuff in MinGW (you can't "as is", due to an FP operand size bug in GAS). If you want LSD tripping without being arrested for posession, just have a look at Ken's ksqrtasm() or indeed any of his stuff. Like abusing LEA as a 3-operand multiply instruction, for example! (Of course, AT&T assembler syntax looks vile to my eyes, but that's another story

)

Post by **Graf Zahl** » Mon Mar 21, 2005 6:35 am

MartinHowe wrote: Like abusing LEA as a 3-operand multiply instruction, for example!

Any decent C++ compiler is doing that as well!

Cutmanmike · Post by **Cutmanmike** » Mon Mar 21, 2005 7:44 am

I can't understand heads or tailes of the programming bit but.......

purdy colours........... <3

Post by **Enjay** » Mon Mar 21, 2005 7:48 am

Graf Zahl wrote:But that was due to drawing all the sprites, not the AI.

Not all of it. Slower machines had a noticable performance hit when all the thing_hates kicked in, even when none of the bad guys were visible on the screen.

58

Cutmanmike · Post by **Cutmanmike** » Mon Mar 21, 2005 7:50 am

Enjay wrote:58

[offtopic]We're getting there my son[/offtopic]

rpeter · Post by **rpeter** » Mon Mar 21, 2005 8:40 am

Fortunately all of Build ( and Duke ) can be built as C-only, although JonoF's C replacements might not be uptodate. A lovely example for optimizing by hand:

int krecipasm(int i)
{ // Ken did this
float f = (float)i;
i = *(int *)&f;
return((reciptable[(i>>12)&2047]>>(((i-0x3f800000)>>23)&31))^(i>>31));
}

Not in a lifetime can I decypher what it does. And I bet the original wasm version wasn't prettier either.

HobbsTiger1 · Post by **HobbsTiger1** » Mon Mar 21, 2005 12:50 pm

Hobbs is happy *glues himself to monitor*

Csonicgo · Post by **Csonicgo** » Mon Mar 21, 2005 3:46 pm

I cannot wait. this wil blow vavoom out of the fuckin' WATER!

Chilvence · Post by **Chilvence** » Mon Mar 21, 2005 4:20 pm

Oh yes great lets get tribal again whee happy I'm eating my own fingers

wildweasel · Post by **wildweasel** » Mon Mar 21, 2005 6:38 pm

I'm psyched. (No, there is no other content to this post.)

Siggi · Post by **Siggi** » Mon Mar 21, 2005 6:55 pm

Does 97 have an intergrated coffee maker?

Sphagne · Post by **Sphagne** » Mon Mar 21, 2005 9:38 pm

How about automated level builder?

MapInfo:

LevelTheme: Hell.
LevelSize: 2560,4000
LevelDifficulty: Hard
MonsterUse: 50,70,120
Detail: 80
Decoration: 300
EndBoss: SpiderMasterMind
MiniBoss: 2: (Baron:5 ; Mancubuc:2,ArchVile)
...

Let's Play!