Re: [Gegl-developer] Qt bindings and gegl_node_set*

[Daniel Sabo <danielsabo gmail com>]

On Thu, Jun 27, 2013 at 3:46 AM, Jon Nordby <jononor gmail com> wrote:

On 27 June 2013 09:15, Alberto Mardegan <mardy users sourceforge net> wrote:

Does setting a property have any immediate effect on the rendering, or
does that happen only when gegl_node_process() is called?
Could the order of setting properties have any effect on the rendering
results or performance?

Setting properties on a node in a graph invalidates the graph. Computing/rendering the invalidated regions is done as a separate step, and it is the application code which controls this. So whether multiple invalidation are coalesced or not depends on that code.

To clarify this, if you set properties one at a time it will invalidate the graph once for each property. If a property changes the size of the node's output you may end up invalidating more than would otherwise be necessary, but it shouldn't be a huge cost.