[fpc-pascal] FPC Graphics options?

[Reimar Grabowski]

On Thu, 18 May 2017 14:52:25 +0200 (CEST)
Michael Van Canneyt <michael at freepascal.org> wrote:

> > Why do you have to *calculate* *all*?  
> 
> Because you want to create an image ? That's what a ray-tracer does AFAIK.
But raytracing isn't the subject here and never was.
Graemes raycasting isn't the subject here either.
 
> I'm not an expert, but I remember writing POVRay scenes that took forever to
> calculate e.g. a chess board with pieces on it. Admittedly, a long time ago.
POVRay is a benchmarking tool ^^

> You assume that you have a GPU to do a lot of work for you...
Yes, because that's what we are talking about.
I replied to this:

"On Wed, 17 May 2017 09:57:11 +0200 (CEST)
marcov at stack.nl (Marco van de Voort) wrote:

> In our previous episode, noreply at z505.com said:
> > 
> > i.e. if you end up using opengl, or its successor, why does it even 
> > matter if FPC pure games without any libs are slow?  
> 
> You still need to calculate all the vertices that you send to the graphics
> card, even if the GPU renders then."

You see OpenGL is a given, as is the rendering on the GPU.

The question is why do I have to *calculate* *all* vertices that I sent to the graphics card.
I am really interested in where this train of thought comes from or if I am missing anything because I am quite sure that you don't have to and mostly don't do.
But only Marco can tell what he meant with his comment.

> because it renders on screen, but what if you don't want to render the scene on 
> screen, but in a bitmap, without GPU...
Well, if it's without GPU then there surely is no need to "calculate vertices" before sending them to the graphics card, or is there?
And personally I would just render the scene in a bitmap with GPU. No reason to not use the hardware you are provided on any system down to raspberry pis. But rendering to bitmaps is the basis for really boring games. ;)

R.