[1/3] dsound: Add support for 32-bit IEEE float buffers

[Chris Robinson]

On Monday, September 13, 2010 12:55:43 pm Owen Rudge wrote:
> +        if (*v < -1.0f) d = -128;
> +        if (*v <  0.0f) d = *v * 128.0f;
> +        if (*v >= 0.0f) d = *v * 127.0f;
> +        if (*v >  1.0f) d = 127;

The way these checks are written out can cause problems, particularly with the 
first two because the if(*v < 0.0f) occurs after the if(*v < -1.0f) check, so 
it won't properly clamp values below -1.0. Something like this:

        if (*v < -1.0f) d = -128;
        else if (*v <  0.0f) d = *v * 128.0f;
        else if (*v >  1.0f) d = 127;
        else if (*v >= 0.0f) d = *v * 127.0f;

should do fine (along with the 16- and 32-bit variants; the 24-bit one looks 
fine). You also don't need to keep the float as a pointer, though I imagine 
the optimizer can handle that.