So, I just made the switch from Windows to OS X with the purchase of a new 15" MacBook Pro. One of the first things I noticed was that it was not (easily or apparently) possible to enable anti-aliasing for P5 sketches that used OPENGL as the renderer. After some Googling for enabling anti-aliasing in JOGL, I realized that I'd need to do it at the application level, specifically where the PApplet instantiates the PGraphicsOpenGL class.

After downloading the source code and some futzing, I managed to create a custom version that allows a user to enable OpenGL anti-aliasing for their sketches. Here are some snippets of what I implemented:

In PApplet, I added a couple variables:

Code:

private boolean isAntiAliased;
private int numSamples;
 

I set the default value in the constructor to true and 0 respectively.

Then I added a couple public methods in PApplet:

Code:

public boolean getIsAntialiased() {
  return isAntiAliased;
}

public void setIsAntialiased(boolean useAntialiasing) {
  isAntiAliased = useAntialiasing;
}

public void setNumSamples(int samples) {
  numSamples = samples;
}

public int getNumSamples() {
  return numSamples;
}
 

Lastly, in the PGraphicsOpenGL class, within the allocate() method, where it first creates a new GLCanvas, I added the following lines:

Code:

GLCapabilities capabilities = new GLCapabilities();
capabilities.setSampleBuffers(parent.getIsAntialiased());
if(parent.getIsAntialiased()) 
  capabilities.setNumSamples(parent.getNumSamples());
canvas = new GLCanvas(capabilities);
 

Now, I'm not sure that this is necessarily the most elegant implementation of enabling anti-aliasing for an OpenGL render, since I'm not terribly familiar with the Processing source code and JOGL. I couldn't find any reference for being able to change the capabilities of the GLCanvas after it has already been instantiated. And a downside to this method is that you must call setIsAntialiased(true) and setNumSamples(XX) before calling the size() method.

In an ideal world you would simply pass it along as an optional parameter with the size method, it seems:

Code:

// The number 4 below indicates that you want
// 4x sampling for anti-aliasing
size(640, 480, OPENGL, 4);
 

Is there any way that this can be implemented in a future build of Processing so that users can enable anti-aliasing from within their sketch as opposed to some driver configuration panel (for Windows users) or no other option, to my knowledge (for OS X users)?

Any insight would be great. Thanks!

One possible way around this would be to create a few classes that extend PGraphicsOpenGL and only implement the constructor, and allocate method.

e.g. create a class PgraphicsOpenGL4xAA which has an allocate method that sets up the sample buffers, but lets the normal PGraphicsOpenGL handle every other function.

You can then create this with size() similar to normal:

size(800,600,"my.library.PGraphicsOpenGL4xAA");

That way you don't lose or ahve to re-implement any of the functionality, and the wrapper classes are small and shuold cause little overhead.

Thanks a lot !!!

Eek.

a) I'm sorry you purchased the Mac Mini with the assumption that you'd be able to run OpenGL-driven P5 applets with any level of anti-aliasing (while maintaining any sort of framerate).

b) I have absolutely no authorative answer for you, but am I wrong in guessing that while a card may have basic OpenGL support, it doesn't necessarily support any degree of Anti-aliasing and would simply "fail silently" when asked to anti-alias a scene in OpenGL?

When I think back to all kinds of cards as they were coming out (when hardware acceleration was just becoming possible), one of the "features" always listed was something like 4x anti-aliasing (or more obviously). So, my assumption (maybe it's bad to assume) is that the card simply doesn't support OpenGL anti-aliasing at any level.

So while the Processing code may be working, it's simply "failing silently" when it attempts to tell your card what to do.

But I will say that most likely, your code will work on those other Macs that have something more than a graphics chip built into the motherboard.

did you make sure to run all of the software updates? sometimes apple slips in a driver update or two that might help. I don't have a mini so i can't say for sure.

Also, if you must, you could try to install windows and see if the windows driver has better luck. Again, this is just conjecture, i haven't tried myself.

I've create a new class that extends the PGraphicsOpenGL class and overwrite the allocate function. It works well but now I've got problems to do to things like this:
Code:

((PGraphicsOpenGLExt) g).gl.glDisable( GL.GL_DEPTH_TEST ); 

When I change the line
canvas = new GLCanvas(capabilities);
back to
canvas = new GLCanvas();
the openGL stuff work.

Does someone know what happens?

Thank you so much watz, i was waiting for this hack for macintel for so long.

The only way to activate AA on Mac was by using an app profile in ATI pref panes. (it is only PPC)

4x AA is simply great.

Glad you like it. The downside is that (as observed by Eskimoblood) when using the hack it is no longer possible to get "trails". The screen is always cleared between frames. I'm not sure if there is a solution that allows anti-aliasing while not erasing the existing image.