Graphics Library for D

[Mike Parker]

On 1/8/2014 9:26 PM, "Ola Fosheim Grøstad" 
<ola.fosheim.grostad+dlang at gmail.com>" wrote:
> On Wednesday, 8 January 2014 at 11:34:53 UTC, Mike Parker wrote:
>> Rendering to a memory buffer to generate png images is a legitimate
>> use case. If Phobos has a graphics API, I would expect that to be
>> supported even when no gpu is present.
>
> Yes, this is true, but that was not the goal stated at the start of the
> thread. The linked framework is a wrapper for a hodge podge of graphics
> technologies that target real time graphics (an internal framework that
> was developed to do graphics for advertising I think).
>
> A generic non-real-time graphics API that is capable of generating PDF,
> SVG and PNG would be quite useful in web-services for instance. But then
> it should be based on the graphics model that can be represented
> efficiently in PDF and SVG.

I could have sworn I read somewhere in this thread that there was talk 
of including it in Phobos at some point. That's the perspective I've 
been arguing from. If it's fully intended to be separate from Phobos, 
then there's no need for any of this and the feature list could 
certainly be more specific.

>
> However, if you want interactive graphics, you enter a different domain.
> An engine that assumes that all geometry change for each frame is quite
> different from an engine that assumes that most graphics do not change
> beyond simple affine transforms.

I wouldn't expect any implementation, generic or otherwise, to assume 
mostly static geometry. You could bet that a simple graphics API in 
Phobos would be used for games by some and for generating pie charts by 
others. It's still possible to get a generic rendering system to handle 
that with decent performance. Yes, it makes for compromises in the 
backend that a more targeted renderer wouldn't need to make, but that's 
the price of genericity.


>
> However the argument against shaders/GPU does not hold, I think. Using
> simple shaders (with your own restricted syntax) does not require a GPU.
> If you can parse it at compile time you should be able to generate D
> code for it, and you should be able to generate code for GL/DX at
> runtime quite easily (probably a few days of work).

This is true. But assuming a) the library is going to be in Phobos and 
therefore b) there is going to be a software backend, and c) there's a 
desire for feature parity between the software renderer and any 
hardware-accelerated backends, then custom shaders increase the 
complexity of the software implementation quite a bit. There are so many 
rules needed to guide the implementation in terms of render quality. Ugh!

That's a lot of assumptions, I know. If this is not going to be in 
Phobos and there's no pressing need for a software renderer then it's 
moot. In that case, the sky's the limit.