Optimizing drawing performance 13 – Apple Newton Programmer’s Newton 2.0 (for Newton 2.0) User Manual

Page 548

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C H A P T E R 1 3

Drawing and Graphics

13-22

Using the Drawing Interface

Notice that there are two types of pictures: bitmaps (a frame with

bits

, a

bounds

, and

mask

slots) and Format 1 PICTs (binary objects of class picture).

clPictureView

can draw both of these types of objects,

so you just need to choose a format and use

SetValue

on the

icon

slot,

as follows:

SetValue(myView, 'icon, kPictureAsBitMap);

or

SetValue(myView, 'icon, kPictureAsPict);

Optimizing Drawing Performance

13

You can use several methods to make drawing functions execute faster.

If you have a fairly static background picture, you can use a predefined PICT
resource. Create the PICT in your favorite drawing program, and use the PICT as
the background (

clIconView

). The graphics system also has a picture-making

function that enables you to create pictures that you can draw over and over again.

If you want to improve hit-testing of objects, use a larger view in combination with
a

ViewDrawScript

or a

ViewClickScript

rather than using smaller views

with an individual

ViewClickScript

. This is especially true of a view that

consists of regular smaller views.

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