hi,

for "my" plotter extension i would like to implement a preview functionality. right now i can't do that because the preview would overwrite the document permanently once one hit the apply button.

it would really help if there was a way to know if the call to the extension was made for the preview (preview checkbox) or the final rendering (apply button), or if the above is not possible, if there was an .inx tag attribute preventing inkscape from using the extensions ouput as the final document while still maintaining preview functionality. maybe it makes sense to implement both.

i could imagine multiple solutions for that: - add a parameter to the extension call identifying the preview state - add an preview state attribute to the document's internal structure (the svg tag perhaps) - add an attribute to the effect tag in the .inx file format: <effect needs-live-preview="true" needs-document="true" discard-final-result="true">

i think it would be a beneficial feature for other extensions as well. i could imagine that an extension could do a rough rendering for preview while still providing the fine rendering for the finished result, this could greatly improve speed and handling on some extensions.

since i am no C programmer i can not do it, but if someone could implement such a feature my eternal gratitude for him/her would be certain.

with kind regards, TimeWaster