Underwater-ish Screen Distortion

This code has been declared by its author to be Public Domain code.

Underwater-ish Screen Distortion by jfk EO-11110 (Posted 22 years ago)
This is the Function that was used in the "Twilight of Gods" Demo for the Underwater Screen distortion Effect. I also tried to distort not only the y axis, but also the x axis, but the effect wasn't much more impressive, tho it was twice as slow, so I decided to use only the y-axis. For the animated Texture that is used as additional Surface layers in underwater zones, I used this effect too, plus the said X-Distortion and a number of further steps. This is a simple thing and maybe it can be done more elegantly and efficiently.
;Underwater FX by jfk of CSP, please mention this in the credits. Graphics3D 640,480,32,1 SetBuffer BackBuffer() camera=CreateCamera() TranslateEntity camera,0,0,-12 ; probably use some fog... CameraFogMode camera,1 CameraFogColor camera,50,100,150 CameraFogRange camera,-100,200 CameraClsColor camera,50,100,150 ; used by screen sinus-distortion fx: Global screenbk=CreateImage(GraphicsWidth(),GraphicsHeight()) Global underw_a ; some dummy content... n=100 Dim o(n) For i=0 To n o(i)=CreateCube() PositionEntity o(i),Rnd(-10,10),Rnd(-10,10),Rnd(-10,10) RotateEntity o(i),Rand(360),Rand(360),Rand(360) EntityColor o(i),Rand(255),Rand(255),Rand(255) Next While Not KeyDown(1) RenderWorld() CaptureScreen() WobbleView() VWait Flip 0 Wend End Function capturescreen() CopyRect 0,0,GraphicsWidth(),GraphicsHeight(),0,0,BackBuffer(),ImageBuffer(screenbk) End Function Function WobbleView() gw#=GraphicsWidth() gh#=GraphicsHeight() underw_a=(underw_a+4) steph#=gh/32 mu8#=gh/60 If underw_a>359 Then underw_a=0 For iif#=0 To gh-4 Step .001 wsin#=(Sin((underw_a+iif)Mod 360.0)*mu8#) CopyRect 0, iif, gw,steph+4, 0,iif+wsin#, ImageBuffer(screenbk),BackBuffer() iif=iif+steph Next End Function

Underwater-ish Screen Distortion by jfk EO-11110

(Posted 22 years ago)

This is the Function that was used in the "Twilight of Gods" Demo for the Underwater Screen distortion Effect. I also tried to distort not only the y axis, but also the x axis, but the effect wasn't much more impressive, tho it was twice as slow, so I decided to use only the y-axis.

For the animated Texture that is used as additional Surface layers in underwater zones, I used this effect too, plus the said X-Distortion and a number of further steps.

This is a simple thing and maybe it can be done more elegantly and efficiently.

;Underwater FX by jfk of CSP, please mention this in the credits.
Graphics3D 640,480,32,1
SetBuffer BackBuffer()


camera=CreateCamera()
TranslateEntity camera,0,0,-12
; probably use some fog...
CameraFogMode camera,1
CameraFogColor camera,50,100,150
CameraFogRange camera,-100,200
CameraClsColor camera,50,100,150



; used by screen sinus-distortion fx:
Global screenbk=CreateImage(GraphicsWidth(),GraphicsHeight())
Global underw_a


; some dummy content...
n=100
Dim o(n)
For i=0 To n
 o(i)=CreateCube()
 PositionEntity o(i),Rnd(-10,10),Rnd(-10,10),Rnd(-10,10)
 RotateEntity o(i),Rand(360),Rand(360),Rand(360)
 EntityColor o(i),Rand(255),Rand(255),Rand(255)
Next


While Not KeyDown(1)
 RenderWorld()
 CaptureScreen()
 WobbleView()
 VWait
 Flip 0
Wend
End


Function capturescreen()
 CopyRect 0,0,GraphicsWidth(),GraphicsHeight(),0,0,BackBuffer(),ImageBuffer(screenbk)
End Function

Function WobbleView()
 gw#=GraphicsWidth()
 gh#=GraphicsHeight()
 underw_a=(underw_a+4)
 steph#=gh/32
 mu8#=gh/60
 If underw_a>359 Then underw_a=0
  For iif#=0 To gh-4  Step .001
   wsin#=(Sin((underw_a+iif)Mod 360.0)*mu8#)
   CopyRect 0,  iif,         gw,steph+4, 0,iif+wsin#, ImageBuffer(screenbk),BackBuffer()
   iif=iif+steph
  Next
End Function