[cairo] Re: Notes on cairo/win32

[J. Ali Harlow]

On 14/01/05 16:21:02, Owen Taylor wrote:

> I have some belief that a C++ class is required to have the same
> in-memory layout as a C structure with the same members in the same
> order.
> 
> I'd be suprised if the Rect class didn't have the memory layout:
> 
> struct Rect_ {
>    int x, y, width, height;
> }
> 
> having private members would just be weird for that.

If you're right, that would certainly work.

> Note there is no reason we can't use C++ in the implementation
> of Cairo. I've never heard of anybody compiling GTK+ for Windows
> with anything other than MSVC or GCC (cross or native).

True, of course.

> The question to me is header file creation... can we create
> redistributable header files that are compatible with the SDK header
> files; the C++ interface is problematical for that because it's
> a lot of inline functions. (Not impossible, just a fair bit of
> work
> 
> The flat interface should be easier.

Yes. I based my headers on Casper Hornstrup's work, but I'm a little  
dubious as to whether he used a clean-room approach to creating them.  
Hard to be sure since I haven't looked at the headers in the Platform  
SDK, but there appear to be things in his headers which don't appear in  
MSDN.

> Right now I'm thinking straight-GDI rather than GDI+ anyways... it
> doesn't sound like there is a big performance advantage to GDI+
> on current Windows,and for acceleration, going to lower levels
> will likely be easier, rather than using the not-quite-a-match
> GDI+.

Ah. I had understood that you were pushing for GDI+ because it gives us  
"anti-aliased paths and alpha-composited primitives". If GDI will do  
what we need then the hardware acceleration, ease of use and  
familiarity would all seem to be benefits.

Ali.