I want to make a image mode array to pick randomly from an image filter mode (BLEND, SCREEN, MULTIPLY, etc.....) but I don't know what datatype to make that array. I tried a string array , but the image transform won't accept the string as a parameter. Any ideas?

Also- is there an easier way to turn down the alpha of an image (rather than screen?) Thanks.

The method Cedric showed is probably best, but if you really wanted to use an array you should be able to use an array of ints.  BLEND, SCREEN, MULTIPLY, etc. are all PApplet integer constants.

Sure.  Here's a link showing all of the Processing constants:

http://dev.processing.org/reference/core/javadoc/processing/core/PConstants.html

The constants used in the filter method are all of the type "static final int" (as opposed to the newer Java enum types).  Here's the (developer) documentation for PApplet.filter():

http://dev.processing.org/reference/core/javadoc/processing/core/PApplet.html#fi...

It shows that filter() just takes an int as the first parameter: "public void filter(int kind)" or "public void filter(int kind, float param)".  When you pass "MULTIPLY" to filter(), for example, you're just passing it a predefined integer.

If you wanted to make an array containing the different integers that correspond to the filter modes, you just use an array of integers:

Code:

int[] modes = new int[8];
modes[0] = THRESHOLD;
modes[1] = GRAY;
modes[2] = INVERT;
modes[3] = POSTERIZE;
modes[4] = BLUR;
modes[5] = OPAQUE;
modes[6] = ERODE;
modes[7] = DILATE;

int randomIndex = int(random(0, modes.length));
int randomMode = modes[randomIndex]; 

You can then use "randomMode" as the first argument when you call filter().

I still think your solution is better, because it's likely that you'd want to pass filter() a different second argument ("level") depending on which mode is randomly chosen.  It's easier to do that with a switch statement.

brewthom11 wrote on Nov 21^st, 2009, 1:00pm:

Whatever you do on the screen, in general it can be done on a PGraphics, ie. on an image.
Beside looping on pixels[] array to alter the alpha, apparently you can use tint() to do that too.