Porting pushStyle(), popStyle(), and boolean() to Processing.js

Project Name

Porting pushStyle(), popStyle(), boolean(), and strokeCap() to Processing.js

Project Description

Processing.js remains incomplete as a port of Processing. Among the features still to be implemented are the functions pushStyle(), popStyle(), boolean(), strokeCap(), and strokeJoin(). The first two functions automatically save style information for later retrieval and reuse. boolean() "converts" arguments into a boolean value. strokeCap() determines how the ends of lines are rendered. strokeJoin() determines how the joints connecting two lines is rendered.

Resources

• github branch repository
• Lighthouse issue tracking
• Processing for the Web @ Mozilla

Project Leader(s)

• Matthew Lam

Project Details

pushStyle() and popStyle()

• The number of states saved is tracked by pushedStates.
• pushStyle() calls curContext.save() and increments pushedStates by one.
• Excess pops are ignored.

Related Mozilla bugs

• #451165 - CanvasRenderingContext2D.fillStyle and strokeStyle accept invalid colours
  • pushStyle() and popStyle() use CanvasRenderingContext2D.save() and restore(). These functions save fillStyle and strokeStyle.

boolean()

• Non-zero numeric values become true
  • Bytes (0's and 1's) are interpreted as numeric values.
• null and undefine become false.
• Boolean arguments are returned as themselves.

strokeCap()

• Modifies context.lineCap.
• ROUND -> context.lineCap="round";
• SQUARE -> context.lineCap="butt";
• PROJECT -> context.lineCap="square";
• Processing default (ROUND) set in function init.
• function size modified to respect previous settings.
  • Used to recreate context and reset settings, which overwrote the desired default.

Things to do

Description	Status	Assigned to	Link
Test cases for pushStyle() and popStyle()	Done	Matthew Lam	Test page
Test cases for boolean()	Done	Matthew Lam	Test page
Test cases for strokeCap()	Done	Matthew Lam	Test page
Test cases for strokeJoin()	Done	Matthew Lam	Test page

Releases

Version	Notes	Resources
0.2	Bug fixes for pushStyle(), popStyle(), and boolean(). Functions now functional.	Patch
0.1	Basic functionality for pushStyle() and popStyle(). Totally untested code for boolean().	Patch

Project News

Date	Notes
Nov. 29, 2009	strokeCap() completed.
Nov. 19, 2009	Release 0.2 announcement.
Oct. 19, 2009	Release 0.1 announcement.
Oct. 12, 2009	Project expanded to include boolean().
Sept. 28, 2009	Basic improvements allow the rudimentary Processing example to function in Processing.js.
Sept. 27, 2009	The initial project proposal has been posted. Repository at github created.