[PD] [Gem]: basic questions

[marius schebella]

hi,
I will try to answer from my understanding, and then maybe iohannes and 
chris can correct me.
usually when you turn gem rendering on, the following happens:
erase the buffer, draw all objects according to the order of gemheads 
(every gemhead can have a sorting number 0-100 and negative values.)
I am not sure if this is buffer 2, but it is definitely not buffer 1.
buffer 1 means: erase the buffer only when gemwin gets a bang. and draw 
only when a gemheads gets a bang.
there is an example 04.pix/10.pixdatasimple that makes use of that 
technique.
one very important object is gemframebuffer. it is not documented (no 
help patch) and is only used in one example 07.texture/10.framebuffer 
but it very very essential. because it enables you to render to a 
texture on the gpu and then use this imagedata as a texture for other 
objects.

[gemhead]
  |
[gemframebuffer]
  |          |
  |          [ID\ !!!
  |
[translateXYZ 0 0 -4]
  |
[pix_image]
  |
[do_your_stuff]
  |
[pix_texture]
  |
[square 4]

------

[gemhead]
  |
  |   [ID\
  |    |
[texture]
  |
[square]

marius.

Roman Haefeli wrote:
> hi all
> 
> the ongoing thread about using gpu to process audio made me realize,
> that there are some basic concepts in gem, that i still don't
> understand.
> 
> what is single buffer mode? what is double buffer mode? how are both
> used? which is the default mode, that assumingly almost everyone uses,
> when doing 'common' gem patches? 
> 
> is it possible somehow to render a frame on arbitrary times? the way i
> used to use gem yet was that i told [gemwin] with wich framerate to
> render. is there a mode or a way, where i can tell gem 'render now' and
> then i get an updated screen, that persists until i do again 'render
> now'?
> 
> are these questions somehow related to each other?
> 
> roman
> 
> 
> 
> 
> 		
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