Dark Bit Factory & Gravity

PROGRAMMING => Freebasic => Topic started by: rain_storm on January 17, 2008

Title: Floor Casting With Xor Texture
Post by: rain_storm on January 17, 2008

28 lines of code (not including white spaces or comments) fast and interesting. Not a bad effort if I say myself

Code: [Select]

' Floor Casting
const resX = 640
const resY = 480
const xres = 320
const yres = 240

#include once "tinyptc.bi"
if (ptc_open("FLOOR CASTING", resX, resY) = 0) then end -1
dim shared as integer buffer(resX*resY)
dim as single u, v, w, camX, camY
dim as integer c, b

while (inkey$ = "")
  camY += 1
  camX = xres*sin(camY*3.14159/180)
  b = 0
  for y = 1 to resY
    w  = -yres / y
    v =  resX*w - camY
    u = -xres*w + camX
    for x = 1 to resX
      c = (u xor v) and 255
      buffer(b+x) = rgb(c,c,c)
      u = u + w
    next
    b = b + resX
  next
  ptc_update@buffer(1)
wend
ptc_close
end 0


Title: Re: Floor Casting With Xor Texture
Post by: Shockwave on January 17, 2008

The requested URL http://dbfinteractive.com/index.php?action=dlattach;topic=2816.0;attach=2749 is infected with Virus.Win32.Virut.av virus

Title: Re: Floor Casting With Xor Texture
Post by: Shockwave on January 17, 2008

False Alert?

Title: Re: Floor Casting With Xor Texture
Post by: rain_storm on January 17, 2008

I hope so maybe there is a virus on my system that infected that program please remove it. I will post only the source

Title: Re: Floor Casting With Xor Texture
Post by: Shockwave on January 17, 2008

It's a great program :)
Have some good karma.

I hope your system is ok.
I use Kaspersky here, Kaspersky detected the threat, I have had flase alerts in the past though especially if the file is crunched with something unusual.

Title: Re: Floor Casting With Xor Texture
Post by: benny! on January 17, 2008

Virus alert here, too. Maybe you can post a uncrunched version!

Title: Re: Floor Casting With Xor Texture
Post by: Jim on January 17, 2008

AVG claims it's a virus too, one with a built in IRC server for stealing stuff off your PC :(  AVG doesn't warn about kkrunchy any more, so this might be the real deal.

Jim

Title: Re: Floor Casting With Xor Texture
Post by: Jim on January 17, 2008

I have replaced the zip with an uninfected one - there's definitely something wrong with the original exe 'cos when I rebuild it's 8kB smaller than the original.  I've PMd rain_storm.

Jim

Title: Re: Floor Casting With Xor Texture
Post by: rain_storm on January 18, 2008

Kaspersky found a lot of infected files on my system its still runnin but it runs very slow I would be glad if someone could recompile for me and upload

Title: Re: Floor Casting With Xor Texture
Post by: Jim on January 18, 2008

I've already replaced the archive in the original post with an uninfected one.
Let us know how you get on with the clean-up operation, or if you need any help!
Jim

Title: Re: Floor Casting With Xor Texture
Post by: Shockwave on January 18, 2008

Quote from: rain_storm on January 18, 2008

Kaspersky found a lot of infected files on my system its still runnin but it runs very slow

:(

At least you will have the problem fixed, even if it takes some time to do a full scan it will be well worth it.
Kaspersky is a great virus killer.

Title: Re: Floor Casting With Xor Texture
Post by: mind on January 18, 2008

nifty.. looks like complete shit at the top though due to no interpolation etc, but thats easily fixed by adding a few bytes to the color calculation accordingly: c = (((u xor v) and 255)/resY)*y

and boom, you have something like this:            compared to this:
(http://web.bitnet.net/johnny/floor.gif) (http://web.bitnet.net/johnny/floor2.gif)

(wouldnt be too hard to add fog instead though, but i'll leave that up to you)

Title: Re: Floor Casting With Xor Texture
Post by: rain_storm on January 18, 2008

Thanks mind thats a great improvement. Worth some good karma I think

Title: Re: Floor Casting With Xor Texture
Post by: mind on January 18, 2008

glad you liked it :)

i found this to be extremely useful tbh, for testing different procedural functions in realtime.

so, i will be tossing you some karma aswell..

Title: Re: Floor Casting With Xor Texture
Post by: va!n on January 19, 2008

@rain_storm:
very great work! Thanks and K++ for sharing this great old skool demo effect source!
Here is the PB converted version available... http://dbfinteractive.com/index.php?topic=2824.0 (http://dbfinteractive.com/index.php?topic=2824.0) ;)

Btw, i did not manged to get this line work in the PB version:

Code: [Select]

c = (((u xor v) and 255)/resY)*y



[Edited]
@rain_storm:
i am not sure how FreeBasic handles pixel coordinates but i think the first pixel will start at 0 instead of 1... if so, i think you have to change your code, else you probaly write diretly somewhere into memory...

Code: [Select]

; your source...

 for y = 1 to resY
    w  = -yres / y
    v =  resX*w - camY
    u = -xres*w + camX
    for x = 1 to resX


Code: [Select]

; change to...

 for y = 0 to resY -1     ; FIXED
    w  = -yres / y
    v =  resX*w - camY
    u = -xres*w + camX
    for x = 0 to resX -1     ; FIXED


Title: Re: Floor Casting With Xor Texture
Post by: Rbz on January 19, 2008

@va!n: be careful with division by zero --> w  = -yres / y 
Variable "y" really should start by 1.

Title: Re: Floor Casting With Xor Texture
Post by: mind on January 21, 2008

not really a problem, the division by zero can be avoided by adding a simple " if y < 1 then w = -yres / (y + 1) else w = -yres / y;"

but pointing it out to him should teach him to read the code more next time :P

Title: Re: Floor Casting With Xor Texture
Post by: rain_storm on January 21, 2008

Or you could simply update ptc at bufer(1) instead of buffer(0) like se

Code: [Select]

  ptc_update@buffer(1)