[GRASSLIST:5835] v.buffer - my buffer is a mess

[Maciek Sieczka]

Hi

Please see the attached screenshots. These are supposed to be the 30km 
buffers for the 'odra_glogow_brzeg_cl' (blue), a vector line, topologically 
clean for sure.
Why are the buffers so awfull? There isn't anything special about my input 
data or whatever. Any guess?

The vbuffer.png was made with 'debug=buffer':

v.buffer input=odra_glogow_brzeg_cl output=odra_glogow_brzeg_cl_buf30
type=line layer=1 buffer=30000 tolerance=0.01 debug=buffer

GRASS_INFO_MESSAGE(20920,1): The tolerance in map units: 300
Lines buffers ...

Rebuilding topology ...
Building topology ...
Registering lines:
1 primitives registered
Building areas:

1 areas built
1 isles built
Attaching islands:

Attaching centroids:

Topology was built.
Number of nodes     :   1
Number of primitives:   1
Number of points    :   0
Number of lines     :   0
Number of boundaries:   1
Number of centroids :   0
Number of areas     :   1
Number of isles     :   1
Number of areas without centroid :   1




And vbuffer2.png made with debug=clean:

v.buffer input=odra_glogow_brzeg_cl output=odra_glogow_brzeg_cl_buf30
type=line layer=1 buffer=30000 tolerance=0.01 debug=clean

GRASS_INFO_MESSAGE(21567,1): The tolerance in map units: 300
Lines buffers ...

Building parts of topology ...
Building topology ...
Registering lines:
1 primitives registered
Topology was built.
Number of nodes     :   1
Number of primitives:   1
Number of points    :   0
Number of lines     :   0
Number of boundaries:   1
Number of centroids :   0
Number of areas     :   -
Number of isles     :   -
Snapping boundaries ...
Registering points ...

All vertices:   117
Registered points (unique coordinates):   116
Nodes marked as anchor     :   116
Nodes marked to be snapped :     0
Snaps:     0
Snapped vertices :     0
New vertices     :     0
Breaking boundaries ...
Intersections:     0
Intersections:    22
Removing duplicates ...
Duplicates:     0
Duplicates:     1
Duplicates:     2
Duplicates:     3
Duplicates:     4
Attaching islands ...
Building topology ...
Building areas:

5 areas built
0 isles built
Attaching islands: Topology was built.
Number of nodes     :   12
Number of primitives:   36
Number of points    :   0
Number of lines     :   0
Number of boundaries:   36
Number of centroids :   0
Number of areas     :   5
Number of isles     :   0
Number of incorrect boundaries   :   14
Number of areas without centroid :   5
Rebuilding topology ...
Building topology ...
Registering lines:
24 primitives registered
Building areas:

5 areas built
0 isles built
Attaching islands: Attaching centroids:

Topology was built.
Number of nodes     :   16
Number of primitives:   24
Number of points    :   0
Number of lines     :   0
Number of boundaries:   19
Number of centroids :   5
Number of areas     :   5
Number of isles     :   0
Number of incorrect boundaries   :   14

Maciek
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