Trouble with graphics display in OS X

James Hurley jhurley at
Tue Jan 25 10:04:04 EST 2005

>Message: 3
>Date: Mon, 24 Jan 2005 17:39:15 -0600
>From: "J. Landman Gay" <jacque at>
>Subject: Re: Trouble with graphics display in OS X
>To: How to use Revolution <use-revolution at>
>Message-ID: <41F58723.1020300 at>
>Content-Type: text/plain; charset=us-ascii; format=flowed
>On 1/24/05 4:15 PM, James Hurley wrote:
>>  I was astonished to discover how much slower Windows was in executing
>>  "Move relative" and "MoveStopped."
>>  The only one of the four which works for me is "Set the loc". My only
>>  problem is the fact that it is so much slower in OS X than OS 9 or Windows.
>I think the test speed results are all highly dependent on the graphics
>card driver and CPU, so they will vary on different machines. OS X uses
>a much higher quality graphics rendering engine than OS 9, which is
>still using the very old QuickDraw. OS X is slower to draw in every
>respect, in any app.
>You might be able to even out the speed difference by setting the "move"
>distances to 2 pixels apart in OS X. I don't think it will be visually
>noticeable and the move should only take half as long.
>Jacqueline Landman Gay         |     jacque at
>HyperActive Software           |


There is also a considerable amount of speed variation depending on 
CPU usage--as much as 30%.

When RunRev is fresh in the morning, with few applications competing 
for attention, a cycle may take 60 ticks. Later in the day, when all 
the kids are up, and demanding to be noticed, the cycle make slow to 
90 ticks. I'm sure all you moms out there are familiar with this.

Just for my own understanding of the display problem, I would like to 
know what determines when the screen is refreshed. There are some 
RunRev actions which have no effect of the display, for example, add 
3 to myVariable, set the myCustomProperty to 3,4, etc. and some that 
do, for example, add 3 to field 1, set the loc of button "myButton" 
to 3,4, set the points of graphic "myGraphic" to 3,4 & return & 
40,50, etc.

Does RunRev engine trigger a screen refresh after the "screen action" 
events, or is the refresh independent of RunRev's activity? It would 
appear, at least in OS X, that RunRev activities which affect the 
screen do not trigger a screen refresh--adding 1 repeatedly to a 
field, for example, will display only a few intermittent figures.

Naive minds want to know.


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