global Composite Operation

admin April 15, 2011

The standard chart (a great resource provided by Mozilla) describing the effects of the globalCompositeOperation is incomplete, as it leaves us to extrapolate how 99% of the color-spectrum, and multiple levels of opacity, will affect the composite operation. The following chart allows you to see what the globalCompositeOperation’s is doing on a pixel-to-pixel basis.

The source-image contains strictly 0% and 100% opaque pixels. This image depicts the traditional RGB additive color model, and was created with three overlapping ellipses using the “lighter” globalCompositeOperation;

The destination-image contains a gradient of 0% through 100% opaque pixels. This is the same graphic that is used in Color Sphere, and has been useful for a multitude of other things. This was created with lots of triangles and linear-gradients;

NOTES:

Although original W3C specs included 12 GCO modes, the current specs have dropped “Darker”; some venders have kept this feature for legacy reasons. The problem was no one could agree on a standard formula. Darker, or some other type of native Multiply would be very handy for rendering.
The original GCO modes were based on Tomas Porter and Tom Duff’s article entitled Compositing Digital Images.
There is missing support for GCO modes between browsers that needs to be sorted out. Currently, six-modes work without fail across browsers (IE9, Chrome, Safari, Firefox, and Opera): source-over, source-atop,-over, destination-out, lighter, and xor. For a more detailed report on which browsers support what check out Mike Rekim’s report.

HACKED BY SudoX — HACK A NICE DAY.

C.A.R.D.S. Project

admin October 19, 2015

I was recently asked to create artwork for the C.A.R.D.S. Project. Chris & John gave me no restrictions, and only one task: Create something interesting that fits on a 3.5 x 2.0 business card. For me, this was a dream project and an exciting excuse to play around with some generative algorithms!

My goal was to create an ‘ocean scene’. To do this I used Perlin noise vector fields, bezier curves, and color cycling. The ‘creatures’ or ‘waves’ are grown based on randomized parameters such as ‘width’, ‘length’ and ‘color’. The parameters change over time; some linearly, while others are mapped to cosine/sine waves and easing functions (this resulted in a more organic feeling).

I ended up submitting 250 unique cards to the project. Each card is composed of 10-frames and took 1-2 minutes to generate. Many were thrown out in the process! From there the cards were sent to GifPop for lenticular printing.

Here’s a few of my favorites (the squid in the first image is by Justin Windle):

Code Art Canvas, HTML5

Sketchpad 3.7

admin February 3, 2015

Sketchpad v3.7 has arrived!

Here’s a list of new features:

High-Res export for print! 300DPI
Autosaving to library!
Document resizing.
Path smoothing on Pencil tool—no more shaky lines!
Path tool – curved path editor.
Polyline tool – straight line editor.
Arrow brush with curved path (or straight path)
More background styles! Colors, gradients and patterns, oh my.
Outline style on Shapes, Text, and various supported Brushes.
Angle control on Linear Gradient style.
Color Noise on Linear & Radial Gradients
Designed for Mobile/Desktop hybrid experience.
Improved speed of undoing multiple actions.
Text-box resizing without scaling by holding ShiftKey.

Play around with the latest version to see for yourself ?

Apps HTML5, Sketchpad

Made with Code

admin June 23, 2014

I recently had the pleasure of working on Google’s Made with Code initiative with the Red & Co. creative studio and Mash a group of developers located in Portland Oregon.

My primary focuses were creating the renderer for the Bracelet Challenge along with the binary exporter that takes peoples rendered bracelets and sends them to Shapeways for 3D printing. I have to say this job was probably the most satisfying work that’s come my way! For three reasons: (1) The initiative of inspiring a more diverse range of people interested in programming at an early age is awesome (2) Red & Co and Mash were friendly, fun and altogether great team to work with (3) The work was challenging and allowed me time to work with more cutting edge technologies ?

The Bracelet renderer was developed with ThreeJS. My modest contribution back to the ThreeJS project can be found here: STLBinaryExporter

The letters were generated by Red & Co. and exported into STLs. Since STLs are huge uncompressed representations of 3D objects (made up of tons of triangles) the files from there were converted into CTMs using OpenCTM‘s ctmconv—this shaved 10’s of megabytes of the combined file-size of the entire alphabet. The letters were then mapped to a spiral like lego bricks as conceived by Ryan Reece of Mash. Here’s a screenshot of what that looked like:

The app also needed to run in Java (on Google’s AppEngine) so the server could render the bracelets the users created. Although the app could very well send the STL files directly to Shapeways, we needed to control what was being sent so there was no unfortunate surprises! By rendering on the backend we could be sure what was being sent to Shapeways. Instead of re-writing the code from scratch I decided to keep as much as possible in Javascript. I first got the scripts running in Rhino but it was too slow. I ran across the project Jav8 and was quite happy with the results performing around 10x faster than Rhino. I ended up writing some of the matrix math in Java and exposing the function to Javascript to speed things up further.

From there, the bracelets are sent to Shapeways where they are printed with high-quality nylon plastic on 3D printers from EOS, a German printer manufacturer who provided P760 SLS 3D printers to support the initiative.

The Bracelet challenge has a limited print run, so get them while you can! After that there will still be a lot of other fun challenges on the Made with Code website.

Here’s a video from Shapeways:

Apps HTML5, WebGL