理解morphic halo

• morph

• Noun

  an actual linguistic form;

  Biology, each of several variant forms of an animal or plant;

  an image that has been processed in this way;

• Verb

  change or cause to change smoothly from one image to another by small gradual steps using computer animation techniques

• halo

• Noun

  a circle of light appearing to surround the sun or moon and resulting from refraction or reflection of light by ice particles in the atmosphere

• Morphic

  Morphic is the name given to Pharo’s graphical interface.

  Morphic is written in Smalltalk, so it is fully portable between operating systems, as a consequence, Pharo looks exactly the same on Unix, MacOS and Windows.

  What distinguishes Morphic from most other user interface toolkits is that it does not have separate modes for “composing” and “running” the interface: all the graphical elements can be assembled and disassembled by the user, at any time.

• History

  Morphic was developed by John Maloney and Randy Smith for the Self programming language, starting around 1993;

  Maloney later wrote a new version of Morphic for Squeak, but the basic ideas behind the Self version are still alive and well in Pharo Morphic:

  • directness

    Directness means that the shapes one the screen are objects that can be examined or changed directly, that is , by pointing at them using the mouse.

  • liveness

    Liveness means that the user interface is always able to respond to user actions: information on the screen is continuously updated as the world that it describes changes.

  All the objects that you see on the screen when you run Pharo are Morphs, that is , they are instances of subclasses of class Morph.

• References

1. Chapter 11: Morphic