Am 01.12.2004 um 06:40 schrieb Peace Jerome:
> When the squeak screen depth is set to 32 and the
> apple is set to thousands of colors the ruler showed
> 32 steps of gray.

This is because "thousands" is 15 bits, that is 5 bits per component 
(red/green/blue), so 32=2^5 sounds about right.

> When the squeak screen depth was reduced to 16 the
> ramp appeared smooth no steps.

This is because Squeak "dithers" gradients in 16 bit mode to make them 
look more smooth. Get a MagnifierMorph and look at the tiny patterns 
...

> When the squeak screen depth was put back to 32 and
> the apple set to millions of colors the ramp looked
> smooth.

As was expected.

> When the screen depth now was reduced to 16 colors the
> ramp looked smooth.

Again, the dithering does a great job and the 16->32 bit conversion in 
the VM does no harm. Not anymore at least, VMs prior to 3.7.5 did this 
wrong (the gradient was distorted).

> The obvious work around is to have the screen depth
> and hardware depth match as often as possible.

Well, 16 bits might be faster as there is only half the bits to be 
kicked around.

- Bert -