[Haskell-cafe] Memory efficiency questions for real-time graphics

[T Willingham]

On Sat, Nov 1, 2008 at 2:11 PM, Sebastian Sylvan
<sebastian.sylvan at gmail.com> wrote:
> On Sat, Nov 1, 2008 at 6:57 PM, T Willingham <t.r.willingham at gmail.com>
>>
>> The per-vertex computation is a quite complex time-dependent function
>> applied to the given domain on each update.  Yet even if it were
>> simple, I would still first implement the formulas in Haskell and
>> leave the optimization for later, if at all.
>
> I'd be very surprised to see a vertex transform that would be faster to
> implement on the CPU than the GPU.

It appears you misunderstood "complex time-dependent function".  This
is quite a bit of Haskell code involving a significant amount of
octonion algebra.  It could, in principle, be put on the GPU, however
that should be the very last step after everything else works.

> There are various ways of writing out your vertex data too, so if it doesn't
> change too often you can still do the transformation on the GPU,

As I previously stated, it changes every frame.

Take a highly complicated function and apply it to N vertices.  Now
increase N until the framerate is affected.  That is where I am.  It
is obvious that any N-sized allocations will cause the framerate to
stutter.  This is not just theoretical: I *see* it as I increase N
while it's running.  This is the point of my initial email, the
subject of which is memory efficiency.