The HTC Dream doesn't have an FPU, or we would be using it :-) The Verizon
Droid and Google Nexus One do have one though.

Keep in mind that "VFP" is really an umbrella for different ARM FPU
technologies:

If I remember correctly:

VFPv1 is now obsolete
VFPv2 is an optional instruction set for ARMv5/ARMv6 CPUs.
VFPv3 is used on ARMv7-based CPU, it is not compatible with VFPv2 as far as
I know.

Also, there is VFPv3-D16 and VFPv3-D32, where the difference is that the
former provides 16 64-bit FP registers to the CPU,
while the latter provides 32. Which one is exactly implemented depends on
the exact CPU model.

Whether OpenGL is faster using floats or fixed points depends on the GPU. I
believe that embedded GPUs only really
support fixed point at that point (and the driver performs floats->fixed
point conversions for you).

The only way to tell is to benchmark on specific devices and compare the
results.

On Mon, Feb 22, 2010 at 2:26 AM, tdom...@googlemail.com <
tdom...@googlemail.com> wrote:

> I'm currently developing a application on a HTC Dream aka T-mobile G1.
> afaik the processor has a FPU coprocessor, called VFP (Vector Floating
> Point) in ARM terms. So far I couldn't find any information about if
> the FPU is used for floating point calculations or if those are
> emulated in software. does anyone have any information about that?
> the opengl implementation supports both fixed point and floating
> point. will my applications be slower when I'm using floating point,
> because they get transformed into fixed point internally? or is
> floating point implemented in hardware?
> thanks for any information in advance :D
>
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