45 replies to this topic

[MadJik]

Tube Effect
(or oblique cylinder?)

What's this?

Photo sample from:
http://www.photo-libre.fr


This is a distort effect plugin. It allows you to distort the image as if you put in on a cylinder...
While moving, if the image leaves the area on a side it will reappear on the other.

In fact it was originally 99% made with CodeLab...(1% for external text editor, and for the icon).

Download the DLL
Plugin TubeOblique.dll
Here is the DLL

The source is available with the plugins package!
http://forums.getpaint.net/index.php?showtopic=7186

How to install?
Close Paint.net
Unzip and place the DLL in your Effect folder usually: C:/Program Files/Paint.NET/Effects

The User interface

X,Y Offset (direction):
...you could choose the direction of the distortion.

Steps factor:
...you could increase the effect of distortion.

Quality:
...increasing the quality is slowering the rendering a bit, and should reduce the pixelisation.

Options:
_ Centered: if checked the borders are moving and the middle of the image is stable.
_ Horizontal flip: if checked the upper part moves in opposite way than the lower part, like a S or Z.
_ Vertical flip: if checked the right part moves in opposite way than the left part, like ~.

Examples:







Attention, need surounding but not everywhere!
Let's test with this simple image. Let's say the blue rectangle is the subject.
In this example the subject is in the middle of the area. The effect takes the full width of the selection and so the subject is moved down:


For a better result (depending on what you are looking for!) you shoud cut/paste in a new image for the time to apply the effect.
Take away left/right margin and leave up/low transparent (for a vertical effect).
Then the effect is fully applied on the subject, most left and most right pixels don't move (or just 1-2 px).



Advanced Example
To make the 'glass' on the first picture:
I've set the background color to transparent.
I've resized the canvas only verticaly.
I mean the picture was (for example) 160x120 I enlarge the canvas to 160x300.
Be sure :
- there is no transparent border on left/right to have a nice tube effect.
- upper/lower borders are transparent...

Then I've duplicated the image.
And Applied Tube V:+0.60 steps 100 not centered, on the top layer
And Applied Tube V:-0.60 steps 100 not centered, on the second layer

And some other effects (shadow, glow, ..), I forgot to use the feather...

Please test it and give your comments...

[barkbark00]

This looks really cool. Would you be able to add anti-aliasing?

[Zulu2]

man.....this is crazy thanks for the plugin

[BuzzKill]

Positioning of the object(you wish to tubulize) in the canvas is vital and can be very tricky.

Cool plugin but it needs some work. Anti-aliasing would be nice. Also, the panelling* of the object can be quite bothersome.


*panelling


Coffee anyone?

[Rick Brewster]

I'm still not sure why you're sampling the selectionRegion.IsVisible() at every pixel. The list of rectangles you get is limited to the selected region anyway, so this will always return true. I tried to tell BoltBait this about 5 times but it has still persisted in the template.

Also, instead of doing:

CurrentPixel = src[srcX,srcY];

try this:

CurrentPixel = src.GetBilinearSample(srcXd, srcYd);

And get rid of the IEEERemainder stuff. It will look much more better.

[barkbark00]

"much more better"

So, you're saying it will look very good?

[BoltBait]

I'm still not sure why you're sampling the selectionRegion.IsVisible() at every pixel. The list of rectangles you get is limited to the selected region anyway, so this will always return true. I tried to tell BoltBait this about 5 times but it has still persisted in the template.

That is true... except for irregular selections.

If you don't check, you'll get issues like this:



Which I ran across when developing the Gradient plugin that I wrote.

Besides, you're the one that gave me the code in the first place.

[MadJik]

@Rick:
BoltBait is in some way my 'guide' so it's not surprising to find some similar stuff...
@BuzzKill and All:
Ok for Antialias but how with Codelab?

[Rick Brewster]

That is true... except for irregular selections.

No, it's completely true especially for irregular selections. The current selection is passed straight to the effect rendering harness. The whole point of the effect system in Paint.NET is that you don't have to worry about things like clipping to the selection, multicore scaling, etc.

If you don't check, you'll get issues like this:



Which I ran across when developing the Gradient plugin that I wrote.

I don't understand what you're showing me here. The layer thumbnail does not update while the effect is running. It sounds like an implementation problem, or you were using a beta version where things were operating differently.

Besides, you're the one that gave me the code in the first place.

No, I didn't give you that part of the code. I tried telling you several times that you don't need to call selectionRegion.IsVisible().

Edit: Woops, I did give you that code. But then I tried to correct myself in the very next post.

[BoltBait]

@BuzzKill and All:
Ok for Antialias but how with Codelab?

Rick already told you... Use src.GetBilinearSample(srcXd, srcYd);

int Amount1=0;  //[-200,200]Horizontal cylinder factor 
int Amount2=0;  //[-200,200]Vertical cylinder factor 

void Render(Surface dst, Surface src, Rectangle rect) 
{ 
    PdnRegion selectionRegion = EnvironmentParameters.GetSelection(src.Bounds); 
    Rectangle selection = this.EnvironmentParameters.GetSelection(src.Bounds).GetBoundsInt(); 

    float RadiusY =(float)Amount1 / 100.0f; 
    float RadiusX =(float)Amount2 / 100.0f; 
    
    long SizeX = (long)(selection.Right - selection.Left); 
    long SizeY = (long)(selection.Bottom - selection.Top); 
    long CenterX = (long)((SizeX / 2.0f)+selection.Left); 
    long CenterY = (long)((SizeY / 2.0f)+selection.Top); 

    for(int y = rect.Top; y < rect.Bottom; y++) 
    { 
        for (int x = rect.Left; x < rect.Right; x++) 
        { 
            if (selectionRegion.IsVisible(x, y)) 
            { 
              float AngleY = (float)Math.Asin(2.0f*(float)(y - CenterY)/(float)SizeY); 
              float srcXd = (float)(Math.Cos(AngleY) * RadiusY * CenterY)+x; 
              if (srcXd < 0) srcXd+=(float)SizeX;
              if (srcXd > SizeX) srcXd-=SizeX; 

              float AngleX = (float)Math.Acos(2.0f*(float)(x - CenterX)/(float)SizeX); 
              float srcYd = (float)(Math.Sin(AngleX) * RadiusX * CenterX)+y; 
              if (srcYd < 0) srcYd+=SizeY; 
              if (srcYd > SizeY) srcYd-=SizeY;

              dst[x,y] = src.GetBilinearSample(srcXd, srcYd); 
           } 
        } 
    } 
}

[MadJik]

Oops, never thought it was for antialiasing... Thanks!
Edited the first post to change this in the code and added more explanations....
Changed the dll also (please download it again!)

[BuzzKill]

Much better! Thanks.

[Rick Brewster]

Well, don't confuse antialiasing and sampling methods.

This may not make the edges smooth.

[BoltBait]

Well, don't confuse antialiasing and sampling methods.

This may not make the edges smooth.

True, but I think barkbark00 was really asking for a better sampling method.

Now, if you leave some space around the image before you run the effect, the sampling method should create a sort of antialiasing. The only problem in this case is when the image repeats.

[Rick Brewster]

Yeah I think you should be fine.

Rotate/Zoom does some weird faux-antialiasing so that the edges of the rectangle are smooth. I forget exactly how it does it; I wouldn't use it as an example

[barkbark00]

Would it be possible to revamp the Rectangular to Polar Conversion plug-in Source to include Bilinear Sampling?

[MadJik]

Would it be possible to revamp the Rectangular to Polar Conversion plug-in Source to include Bilinear Sampling?

Few code to change.
I would give a chance to Programmerman (plugin author) to update...
Post your request on his topic... Or update the plugin yourself as the source is provided (I will do it in few days if nobody answers).

[barkbark00]

Thanks Madjik, I posted the request in his thread.

I would do it but I am lost when it comes to C#.

[MadJik]

Tube Effect new version 2007/05/03

What's new:

The two sliders ranges are now : -500% to +500% and default 0%
Horizontal slider is inverted (more 'natural').

Better behave for none square image while moving, if the image leaves the area on a side it will reappear on the other.

The Effect DLL

You can download the effect DLL here: Tube Oblique.dll

Put this file in your c:/program files/Paint.NET/Effects directory. You need to restart Paint.Net.
The Effect is in the Effects menu under Distorts...

Source Code

int Amount1=0;  //[-500,500]Horizontal cylinder factor
int Amount2=0;  //[-500,500]Vertical cylinder factor

void Render(Surface dst, Surface src, Rectangle rect)
{
  PdnRegion selectionRegion = EnvironmentParameters.GetSelection(src.Bounds);
  Rectangle selection = this.EnvironmentParameters.GetSelection(src.Bounds).GetBoundsInt();

  float RadiusY =-(float)Amount1 / 100.0f;
  float RadiusX =(float)Amount2 / 100.0f;
  float Distort = 2.0f;

  long SizeX = (long)(selection.Right - selection.Left);
  long SizeY = (long)(selection.Bottom - selection.Top);
  long CenterX = (long)((SizeX / 2.0f)+selection.Left);
  long CenterY = (long)((SizeY / 2.0f)+selection.Top);
  ColorBgra CurrentPixel; 

  for(int y = rect.Top; y < rect.Bottom; y++)
  {
    float AngleY = (float)Math.Asin(Distort *(float)(y - CenterY)/(float)SizeY);
    float srcXd = (float)(Math.Cos(AngleY) * RadiusY * CenterY);
    for (int x = rect.Left; x < rect.Right; x++)
    {
      //CurrentPixel = src.GetBilinearSample(x, y); // Get the current pixel 
      int srcX = (int)Math.IEEERemainder((int)srcXd + x,SizeX);
      if (srcX < selection.Left) srcX+=(int)SizeX;
      if (srcX >= selection.Right) srcX-=(int)SizeX;

      float AngleX = (float)Math.Acos(Distort *(float)(x - CenterX)/(float)SizeX);
      float srcYd = (float)(Math.Sin(AngleX)* RadiusX * CenterX);
      int srcY = (int)Math.IEEERemainder((int)srcYd + y,SizeY);
      if (srcY < selection.Top) srcY+=(int)SizeY;
      if (srcY >= selection.Bottom) srcY-=(int)SizeY;

      CurrentPixel = src.GetBilinearSample(srcX, srcY);
      dst[x,y] = CurrentPixel;
    }
  }
}

[barkbark00]

I've always liked this plugin...

Would it be possible to center the effect? That way you wouldn't need to piece the image back together if part of it went of the canvas...