Author Topic: What I've done?! O.o  (Read 8197 times)

0 Members and 1 Guest are viewing this topic.

Offline GreenFreak

  • LV4 Regular (Next: 200)
  • ****
  • Posts: 191
  • Rating: +16/-1
    • View Profile
What I've done?! O.o
« on: February 09, 2013, 07:34:09 am »
After writing some programs on my ti 84+, I made it to get something work O.o never mind that i am able to do sth. like that O.o

a little buggy and slowy though running at 15mhz..

can someone help me please to speed this up? :(

i have to fix the fishbowl-effect btw..
« Last Edit: February 09, 2013, 07:36:49 am by GreenFreak »

Offline TIfanx1999

  • ಠ_ಠ ( ͡° ͜ʖ ͡°)
  • CoT Emeritus
  • LV13 Extreme Addict (Next: 9001)
  • *
  • Posts: 6173
  • Rating: +191/-9
    • View Profile
Re: What I've done?! O.o
« Reply #1 on: February 09, 2013, 08:35:48 am »
Is this the beginnings of a raycaster?

Offline GreenFreak

  • LV4 Regular (Next: 200)
  • ****
  • Posts: 191
  • Rating: +16/-1
    • View Profile
Re: What I've done?! O.o
« Reply #2 on: February 09, 2013, 12:10:58 pm »
Yes ;)

Offline epic7

  • Chopin!
  • LV11 Super Veteran (Next: 3000)
  • ***********
  • Posts: 2200
  • Rating: +135/-8
  • I like robots
    • View Profile
Re: What I've done?! O.o
« Reply #3 on: February 09, 2013, 01:33:28 pm »
Dangit, I wish I could do that :P

Offline DJ Omnimaga

  • Clacualters are teh gr33t
  • CoT Emeritus
  • LV15 Omnimagician (Next: --)
  • *
  • Posts: 55941
  • Rating: +3154/-232
  • CodeWalrus founder & retired Omnimaga founder
    • View Profile
    • Dream of Omnimaga Music
Re: What I've done?! O.o
« Reply #4 on: February 09, 2013, 02:06:34 pm »
Did you attempt doing raycasting or did you accidentally create it? O.O

Offline fb39ca4

  • LV10 31337 u53r (Next: 2000)
  • **********
  • Posts: 1749
  • Rating: +60/-3
    • View Profile
Re: What I've done?! O.o
« Reply #5 on: February 09, 2013, 07:45:11 pm »
To remove the fisheye effect, you will want to calculate the distance of the walls not from the camera position, but from a line that goes through the camera position and is perpendicular to the view direction.

Offline TIfanx1999

  • ಠ_ಠ ( ͡° ͜ʖ ͡°)
  • CoT Emeritus
  • LV13 Extreme Addict (Next: 9001)
  • *
  • Posts: 6173
  • Rating: +191/-9
    • View Profile
Re: What I've done?! O.o
« Reply #6 on: February 09, 2013, 09:21:21 pm »
Looks like a nice beginning. :) I'm sure you'll have fun optimizing it.

Offline Deep Toaster

  • So much to do, so much time, so little motivation
  • Administrator
  • LV13 Extreme Addict (Next: 9001)
  • *************
  • Posts: 8217
  • Rating: +758/-15
    • View Profile
    • ClrHome
Re: What I've done?! O.o
« Reply #7 on: February 10, 2013, 10:27:26 pm »
All you have to do to remove the fishbowl effect is multiply by cos(θ) where θ is the angle from dead-ahead (see http://www.permadi.com/tutorial/raycast/rayc8.html for an explanation).

Nice job—raycasting is always fun :D




Offline Sorunome

  • Fox Fox Fox Fox Fox Fox Fox!
  • Support Staff
  • LV13 Extreme Addict (Next: 9001)
  • *************
  • Posts: 7920
  • Rating: +374/-13
  • Derpy Hooves
    • View Profile
    • My website! (You might lose the game)
Re: What I've done?! O.o
« Reply #8 on: February 10, 2013, 10:55:27 pm »
What is raycasting?

THE GAME
Also, check out my website
If OmnomIRC is screwed up, blame me!
Click here to give me an internet!

Offline epic7

  • Chopin!
  • LV11 Super Veteran (Next: 3000)
  • ***********
  • Posts: 2200
  • Rating: +135/-8
  • I like robots
    • View Profile
Re: What I've done?! O.o
« Reply #9 on: February 10, 2013, 11:05:57 pm »
I can't really give a good description myself, but the graphics kinda look like dis:


http://en.wikipedia.org/wiki/Ray_casting
« Last Edit: February 10, 2013, 11:07:27 pm by epic7 »

Offline Sorunome

  • Fox Fox Fox Fox Fox Fox Fox!
  • Support Staff
  • LV13 Extreme Addict (Next: 9001)
  • *************
  • Posts: 7920
  • Rating: +374/-13
  • Derpy Hooves
    • View Profile
    • My website! (You might lose the game)
Re: What I've done?! O.o
« Reply #10 on: February 10, 2013, 11:07:32 pm »
Sounds interesting, good luck with it! :D

THE GAME
Also, check out my website
If OmnomIRC is screwed up, blame me!
Click here to give me an internet!

Offline fb39ca4

  • LV10 31337 u53r (Next: 2000)
  • **********
  • Posts: 1749
  • Rating: +60/-3
    • View Profile
Re: What I've done?! O.o
« Reply #11 on: February 10, 2013, 11:56:38 pm »
What is raycasting?
It means projecting a ray into an environment to render it. In this case, rays are cast into a 2D grid of tiles, one for ever column of the screen, and the distance the rays travel is used to calculate the vertical height of the wall rendered.

Offline GreenFreak

  • LV4 Regular (Next: 200)
  • ****
  • Posts: 191
  • Rating: +16/-1
    • View Profile
Re: What I've done?! O.o
« Reply #12 on: February 11, 2013, 04:59:17 am »
All you have to do to remove the fishbowl effect is multiply by cos(θ) where θ is the angle from dead-ahead (see http://www.permadi.com/tutorial/raycast/rayc8.html for an explanation).

HAHAHA ;D I used this website to create this ;D
I don't understand removing the fishbowl-effect though.. in other words: If I multiply cos(r1) (the angle of the ray being cast) with the calculated distance, the result looks somehow... wierd..

Did you attempt doing raycasting or did you accidentally create it? O.O

It was my goal to create a raycastern ;)

__________

Can someone help me to optimize this? I dont know how to do that :/

Offline MGOS

  • LV6 Super Member (Next: 500)
  • ******
  • Posts: 336
  • Rating: +95/-0
    • View Profile
Re: What I've done?! O.o
« Reply #13 on: February 11, 2013, 08:20:06 am »
Some time ago, I made my own raycaster, however I halted the project... :/ I need to finish it some day

Yours looks awesome so far :)
Looking at your code, I realized that it is quite slow. You only draw 1/4 segments of the screen, and it is running at 15 Mhz. I'm not an expert at raycasting, but I think you need to restructure parts of the code to really optimize it. Still, here are some minor optimization tricks you could use (but I don't think they really matter that much):

Code: [Select]
Pt-Off(0,,Pic0,L3)
If pxl-Test(V/8,W/8,L3)
Using a sprite is a cool idea to store the map, but the pixel-test function is incredible slow (and you're doing that a lot each frame!). Try directly accessing the data, e.g. in an 2d array/matrix etc.



The next optimization helps almost everywhere:
If size doesn't matter, use a bunch of /2 instead of dividing by a power of 2. For example:
A/2/2/2 is faster than /8
This trick works due to the fact that /2 is replaced by a shift operation, whereas every other division calls a routine to divide (which is kinda slow)

Code: [Select]
√(((abs(X-V)²)+(abs(Y-W)²)))→GHere you can leave out the abs(), because squaring gets rid of the sign. You don't even need the first parenthesis. So:
Code: [Select]
√(X-V²+(Y-W)²)→G


Code: [Select]
If r1<64 or (r1>192)Almost in every case you can substitute a logic "or" by an addition.
Code: [Select]
If r1<64 + (r1>192)


I think the slowest part of your code is this, I don't know how to optimize this though, because I don't understand what you want to do with that.
Code: [Select]
Lbl TH
abs(Y-W)*128//sin(r1-r2)*cos(r1-r2)//128→U
r1<128?U+X→V,X-U→V
Return

Lbl TV
abs(V-X)*128//cos(r1)*sin(r1)//128→U
Return
This code looks slow because of signed division and trigonometry. These functions are also called a lot each frame!



Also, if you need a function only once in the code, you can type it inline where you need it to save some bytes and cycles without the call.
If you want to keep readability, you can include them in another program.
Also, what helps reading the code is the C++ style function calling syntax:
Function(arguments) instead of sub(Function,arguments)
For example:
Code: [Select]
sub(TH,r1,128) becomes TH(r1,128)


I guess that's my part for now, maybe I take a closer look on it later. I hope it helps you a bit and good luck with your project.


Offline Matrefeytontias

  • Axe roxxor (kinda)
  • LV10 31337 u53r (Next: 2000)
  • **********
  • Posts: 1982
  • Rating: +310/-12
  • Axe roxxor
    • View Profile
    • RMV Pixel Engineers
Re: What I've done?! O.o
« Reply #14 on: February 11, 2013, 10:15:20 am »
Something you absolutely need to know : if you want to use trig, just build some LUTs (look-up tables, tables to hold constant values instead of recalculating them) and leave sin() and cos() alone. Do that at the really beginning of your code :

:E90D3→°SinLUT+2→°CosLUT
:L1→SinLUT+256→CosLUT       // L1 or whatever free RAM area of at least 512 bytes
:~1       // the negate sign, not the minus
:For(256)    // 256 possible angles, from 0 to 255
:sin(+1→r1)→{r1+SinLUT}
:cos(r1)→{r1+CosLUT}
:r1
:End


And then, replace all of your sin(r1) with sign{r1+SinLUT} and all of your cos(r1) with sign{r1+CosLUT}, but you'll have to make sure that r1 can't go above 255. You'll have a great speed gain, you'll see.
« Last Edit: February 11, 2013, 10:15:49 am by Matrefeytontias »