KGA Editing Toolsផ្ទាំងអន្តរកម្ម
Buffer
បង្កើត buffer ពី features ដែលបានជ្រើស ទៅក្នុងស្រទាប់ polygon ដូច Modify Features ▸ Buffer ក្នុង ArcGIS Pro។
- រកឃើញនៅឯណា
- Processing ▸ Toolbox ▸ KGA Toolbox ▸ KGA Editing Tools ▸ Buffer
- លេខសម្គាល់ algorithm
- kga:buffer_features
- ប្រភេទឧបករណ៍
- Interactive dialog — modeless, owns a map tool, needs the QGIS canvas
ទិដ្ឋភាពទូទៅ
Replica of the ArcGIS Pro Modify Features > Buffer pane. Hover a feature of any geometry type, see its buffer drawn in cyan, and click to write it into a polygon layer of your choosing.
A well becomes its protection zone; a canal becomes its right of way; a village point becomes its service area.
Pro's pane is short — a template, a distance and a unit — and so is the top of this one. The end-cap and corner controls below it are QGIS's own, and they are on the pane rather than buried because a right of way that overshoots its channel by the buffer radius is a real error, not a cosmetic one.
ប៉ារ៉ាម៉ែត្រ
The algorithm takes no Processing parameters — running it opens the pane. The controls below are the pane's.
| ផ្ទាំងគ្រប់គ្រង | ប្រភេទ | តម្លៃលំនាំដើម | ការពិពណ៌នា |
|---|---|---|---|
| Layer | Layer combo | the active layer | The source features are read from here. Any vector layer. |
| Template | Polygon layer combo | the source layer when it is a polygon layer | The polygon layer the buffers are created in. ArcGIS calls this the template. There is no fall-back to the source: buffers are polygons and the source may be lines or points. |
| Distance | Number + unit combo | 10.0 | How far out the buffer reaches. Must be greater than zero. |
| Side | Combo box | full buffer | One-sided buffers only mean anything for a line; a point or a polygon is always buffered all round. |
| End caps | Combo box | Round | How a buffered line ends. Round overshoots the last vertex by the buffer distance; flat stops on it. |
| Corners | Combo box | Round | How the buffer turns a corner. |
| Segments per quarter | Spin box (1–64) | 8 | Straight segments used to draw a quarter circle. Higher is smoother and heavier. |
| Combine the buffers into one feature | Checkbox | unticked | Only means anything when a drag catches several features at once: their buffers are merged, so a chain gives one corridor rather than a stack of overlapping polygons. |
| Copy the source attributes | Checkbox | ticked | Carries the source values across by field name. |
| Buffer | Toggle button | up | Puts the tool in hand. It stays down while the map is in Buffer mode. |
| Reset | Button | — | Sets the running count back to zero, and stops what has been written so far being off limits — so a buffer can itself be buffered. |
| Close | Button | — | Closes the pane and gives the canvas back to the previous tool. |
របៀបប្រើ
- Open KGA Editing Tools > Buffer. Close the Processing window once the pane appears.
- Pick the source Layer and the Template polygon layer.
- Set the Distance and its unit.
- Press Buffer — the button stays down.
- Hover a feature: its buffer is drawn in cyan. Click to write it.
- Or press, drag a path across several features, and release to buffer them all in one go.
- Press Buffer again, or Close, when you are done.
លទ្ធផល
- Buffer polygons written into the template layer, one per source feature (or one merged corridor when Combine is ticked and a drag caught several).
- Source attributes carried across by field name when Copy the source attributes is on.
- A running count and a status line in the pane after each press.
កំណត់សម្គាល់ និងដែនកំណត់
- Distances are honest on a layer stored in degrees. The buffer is computed in the matching UTM zone and brought back, so a 30 m setback is 30 m at the equator and 30 m in the north.
- The tool skips its own output. A buffer contains the feature it came from, so without this the next hover would buffer that buffer, and the click after it would buffer that — one ring wider every time. Reset clears the exclusion when you genuinely want to buffer a result.
- One press is one undo step. A drag across several features is still one step.
- A combined buffer whose parts do not all overlap has to be split when the target is a single-part layer; the status line says so rather than leaving the tick box looking like it did nothing.
- The pane stays open while you work, and it owns the map tool — the QGIS select tool is not involved.
- The tool cannot run headless or inside a model.