Two-monitors (Mac OS X) - Blender doesn't work

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Two-monitors (Mac OS X) - Blender doesn't work

Post by foxcorner » Thu Jul 28, 2005 3:41 am

Hi all,

I'm new to Blender, and I'm looking forward to getting started.

I have 2.36 on Mac OS X 10.3.9.

I have a Radeon 7500 in my G4, with two monitors attached. Note that the screen resolutions of the two monitors are not the same, due to different monitor sizes (1600x1200 and 1280x1024).

If I disconnect the smaller monitor and reboot, so that the Mac runs with just one monitor, then Blender is fine.

However, if I bring it up with both heads, Blender appears (though the splash image never shows), and all its operations are painfully slow - such as 40 seconds for responding to a menu click. And I get the feeling that 3D functionality isn't working either, though I usually give up as soon as I can get to the quit item on the menu (about 1.5 minutes!). I get a lot of beachballing.

I'm not one of those wanting to spread Blender's UI across the two monitors - my objective is to have Blender on the main screen and Firefox (say) with a tutorial on the smaller screen.

Does anyone know why Blender doesn't like my setup, and what I can do about it?


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Post by solmax » Thu Jul 28, 2005 4:48 pm

i think it's due to the old graphic card (probably with low ram). i have similar difficulties (on one monitor) with a GeForce2MX when switching to true-color. consider, two monitors need much more ram for the larger display area.

so try to lower the resolution, reduce colors to thousands, or get a decent graphics card ( i know, it's much more difficult than when having a pc). a radeon 9000 could suffice.

Fire Angel
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Post by Fire Angel » Wed Aug 03, 2005 7:11 pm

The graphics card you are using doesn't have enough RAM.

The reason most of your apllications run just fine in this environment and Blender doesn't is simple; proper native OS X applications pass all the screen update requests to the Aqua system and it uses the memory on the graphics card to provide workspace for the Open GL screen driver, storage for icons, buttons etc. as well as to display the screen data itself via the Open GL driver.

Blender, in order to be so easily ported from one machine to another, does not update the screen by asking the Aqua system to do it. Instead at startup it asks the system for its own "port" to the graphics card and then uses workspace of its own in the graphics card's RAM to store workspace, icons, etc and then passes the image out to the Open GL system to draw as one single rectangular image each time it updates the window.

Effectively your system is being asked to run two Open GL drivers at once, the Aqua one and the Blender one and it just cannot do that in the memory available on your card while running two screens.

There isn't enough graphics memory on my system either, so when running Blender I have to switch to 16-bit colour (thousands of colours) instead of the usual 32-bit (millions). I run a 1600x1200 desktop on a large 21 Inch CRT, and have a mere 16Mb graphics card.

I am aiming to get an ATI Radeon 9200 PCI Mac edition graphics card later this year, the 128Mb one; it's the most up to date card I can get for my old blue and white G3; your G4 will probably have more options, depending upon which G4 it is exactly.

Summing up:

You can run Blender sessions in 16-bit colour for a while, OR get a better graphics card OR wait till you can afford a more up-to-date Mac.

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Post by foxcorner » Thu Aug 04, 2005 7:52 am

Thanks for clarifying it for me. I'll try decreasing the
color depth and see what happens. Can't justify
the expense of a new card right now. :-(

All the best!


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