Claus Cyrny wrote:
Can anyone suggest to the newbie a good way to make a stable, easily manipulated construction of the above curve in inkscape-cvs?
Do you have a bitmap of the logo somewhere?
The logo resembles a concentric pair of 'G' characters, with a few flourishes. The task to break the circle, remove a segment of the arc and extend the endpoints with curves is roughly equivalent.
I worked late to figure it out in inkscape-cvs. The logo turned out well, considering it was my first inkscape document. The annotated steps were roughly as follows:
1. Make the circle as a shape.
2. Convert circle to a path.
3. Select two of the four control nodes, insert a node.
4. Inserted node will appear at midpoint on path between selected nodes.
6. Do not move any nodes yet, you'll damage path's circularity.
5. Repeat steps 3,4 recursively until you have a node close enough to your desired cut point at each side of the segment to be removed.
7. Select the desired cut node and 'cut path at node'. Repeat for other side.
8. Selecting the node of the cut segment can be difficult, since they share the same location as nodes on the preserved path. Use undo immediately if you select the wrong one. You definitely don't want to disturb nodes relating to the curvature of your circle.
9. Clean up extra nodes near the endpoints *before moving any*. I've found that you can often remove some of the intermediate nodes placed halfway between other nodes. Removal of a node will only be practical if there is enough weight available in the remaining nodes to replicate the original curvature. Ride the undo button immediately if you remove a critical node and lose curvature.
Based on the successful experience I had making this logo, and learning inkscape in general, I'd like to offer the following usability observations. The following would make this type of editing easier:
A. Selected control nodes should be more visibly indicated. Their selected status is hard to see.
B. There should be a keyboard shortcut to toggle a mode highlighting richer bezier info on the selected path. The user would see, node number 0..N, degree, etc. for each node, near the node. This would be used in enhancement D, among other places.
C. For multiple nodes sharing the same location, you should be able to keep clicking the spot to cycle through the various nodes, even if they're on different paths. This is probably a general 'drill-down selection' feature request, not just paths.
D. There should be some control over how far along the path between selected nodes the inserted node appears. A toolbar slider going from 0 to 1 would be ideal. The 0 end would be the lower-numbered selected node (i.e. nearer the start of the path), 1 the higher numbered node. Moving the slider to 0.25 would place the inserted nodes one quarter of the way along the path segment between the two selected nodes. This would save a lot of the recursive subdividing I had to emply in my logo.
E. The degree of each node needs to be more integrated in the visual feedback. I *think* that the change from square to diamond indicates degree now. I'm not sure how to increase/decrease the degree of a particular node. The help tip should probably indicate how to do that when paused over a path node.
All in all, I couldn't be more impressed with inkscape. Its definitely going to be my staple drawing application. Thanks!