A way to add fancy effects to your sketches


I recently discovered a way of adding fast/efficient effects to Processing sketches.
Unfortunately, this method only supports the FX2D renderer, as AWT does not support effects.

The method is quite simple:

import javafx.scene.canvas.*;
import javafx.scene.effect.*;
import javafx.scene.paint.Color; // JavaFX uses different colors than Processing

GraphicsContext ctx;
GaussianBlur fxGaussianBlur = new GaussianBlur(20d); // the 'd' stands for 'double'
DropShadow fxDropShadow = new DropShadow(15d, 0d, 20d, Color.gray(0, 0.2)); // we have to use the Color JavaFX class becasue JFX does not support Processing colors (kind of obviously)

void setup() {
  size(256, 160, FX2D); // it is crucial to set the FX2D renderer!
  // in order to apply effects we need to get the 'native' graphics context of our canvas
  ctx = ((Canvas) surface.getNative()).getGraphicsContext2D();

void draw() {
  // this applies the previously created effect to subsequent draw calls
  rect(32, 32, 64, 64);
  // to disable the effect, just set it to `null`
  rect(64, 64, 64, 64);
  ctx.setEffect(fxDropShadow); // material design-style drop shadow
  ellipse(192, 64, 48, 48);

Here’s a screenshot:


As one might notice, those effects are way faster than the built-in filters, and provide similar functionality, if not more flexible.
You might’ve also noticed the use of the Color class instead of ints/Processing colors. This Color class is actually quite useful, however unsupported by Processing itself: Color javadoc

Another nice thing one might do using this GraphicsContext is gradients. Yeah, gradients are now possible without having to draw thousands of lines! Just a rect(), ellipse(), or any shape drawing call, and you’re all set! This is how you can use gradients:

import javafx.scene.canvas.*;
import javafx.scene.paint.*;

GraphicsContext ctx;

LinearGradient gradient;

void setup() {
  size(256, 160, FX2D);
  ctx = ((Canvas) surface.getNative()).getGraphicsContext2D();
  /* I like to use the valueOf() function of the LinearGradient class,
     because it provides a simple, CSS-like way for defining gradients. */
  gradient = LinearGradient.valueOf("linear-gradient(" +
                                    "from 0% 0% to 100% 100%," +
                                    "black 0%, white 100%)");

void draw() {
  fill(#ff00ff); // we assign a dummy color due to how Processing draws fills and strokes internally
  ctx.setFill(gradient); // use setStroke for strokes
  rect(0, 0, width, height);

Here’s a reference for LinearGradient.valueOf(String).

And here’s a screenshot:


There are so many more things you can do with the GraphicsContext! In fact, I highly suggest you check out its javadoc, because direct access to it really expands upon your drawing possibilities.

Thank you for reading!