Title: OpaqueMove Movement Speed


Factors Influencing Speed

Intuition was never designed for opaque window movement or sizing, and the
fact that it can be done at all is a testimonial to its design and
flexibility. There are other window systems on the Amiga which can provide
faster opaque window movement than can Intuition; for example, the EGS system
bundled with many graphics cards does so. However, Intuition can do a
manageable job at this, especially on high end 68040 or 68060 systems with
accelerated graphics cards such as the GVP Spectrum or CyberVision 64. There
are several factors which can affect window dragging speed during opaque
movement:

   o The largest factor is the speed of your hardware. Both CPU speed and
     graphics speed are important. Standard amiga ECS or AGA graphics are
     very slow in anything beyond 1 or 2 bitplanes, but modern graphics cards
     are faster. A 68040 (good) or 68060 (better) helps as well.

   o Generally, a 68060 is more important for opaque sizing than it is for
     movement. Opaque sizing requires tremendous system resources to
     recalculate the window contents with each mouse movement event. This is
     not a task for lightweight systems. The more complex the window, the
     more necessary a fast CPU is.

   o Background pictures on workbench screens can be either slow or fast on
     graphics cards, depending on the software you use, whether you have
     installed any patches such as IPrefs2Fast, and so on. Currently, MUI
     public screens may use background bitmaps, although MUI redraws these
     faster for small patterns than for large.

   o The number of windows on the screen, and the degree to which they
     overlap, affect refresh speeds. The more windows there are, the slower
     window redraws are. Also, moving a window in front of or behind another
     causes one or the other to be redrawn, which causes delays. The impact
     of this is dependent on the speed of your computer and graphics card. It
     isn't too bad on a 68040 or 68060 system unless there are a lot of
     windows open. It might be a lot slower on a 68030 or a system with a
     slower graphics card.

   o The depth of the screen makes a big difference on some Amigas. On AGA
     Amigas, windows on deeper screens are updated slower than on more
     shallow screens. With most graphics cards, 8 plane screens are the
     fastest, while 16 and 24 bit are slower.

   o Bigger windows are refreshed slower than small. This effect is
     particularly noticeable for AGA screens, since the AGA blitter is quite
     slow.

   o Intuition moves smart-refresh windows in a manner which is not optimal.
     Especially on accelerated graphics cards, these windows are moved much
     slower than simple refresh windows. It may be necessary to toggle off
     smart-refresh window opaque movement to obtain reasonable speeds, or to
     use a patch such as qlayers to speed this up.

   o MUI can do very complicated things with window layout. It can map
     different images to every button, region, and control in a window. Doing
     this will of course slow down that window's refresh speed. Generally, it
     is best to use either small patterns, better still, solid colors for
     objects. See the example windows in the User Interface section of this
     document for a good looking MUI interface that uses only solid colors.

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