# Line Geometry This function block provides a single, flexible tool for a wide range of line and geometry operations: angles, distances, intersections, projections, midpoints, segment extraction and more. It can produce numeric results, points, extra operation-specific data and (optionally) an annotated image for visualization. ## đŸ“Ĩ Inputs * `Input Image` Optional image used for visualization overlays (if you want drawn lines, points or contours). * `Line 1` Required for most operations. Accepts a line described as \[(x1, y1), (x2, y2)] or compatible shape input. * `Line 2` Required for angle / intersection / some distance operations. Accepts a second line in the same format. * `Anchor Point` Optional point (x, y) used by projection and point-to-line operations or when a contour is supplied for shape intersection. ## 📤 Outputs * `Output Image` Annotated image (if `Input Image` is provided and `Show Visualization` is enabled). * `Result` Numerical result of the selected operation (for example angle in degrees or distance in pixels). * `Point Output` A point result when the operation yields a coordinate (e.g., intersection, projection, midpoint). * `Extra Output` Operation-specific data (for example segment endpoints, list of intersection points, or other debug info). ## 🕹ī¸ Controls * `Operation Type` Choose the geometry operation to perform (e.g., Angle Between Lines, Intersection Point, Segment Extraction, Projection). * `Offset (px)` Slider used by segment / projection operations to apply an offset in pixels. * `Interpolation Factor` Slider (0–100%) used for interpolation-based operations (segment extraction, projection along line). * `Show Visualization` Checkbox toggles annotated `Output Image` drawing when an `Input Image` is provided. ## đŸŽ¯ Key Features * Single multi-purpose block covering many common geometry tasks. * Context-sensitive behavior: only the outputs relevant to the selected operation will contain meaningful data. * Optional visual overlays: draw lines, midpoints, intersections, projections and segments directly on the provided image. * Interactive tooltips and control hints help you select the right inputs and parameters for each operation. ## ⚙ī¸ How it runs When executed, the block reads the connected sockets and the selected `Operation Type`. It performs the requested geometric computation using the provided `Line 1`, optional `Line 2` and optional `Anchor Point`. If an `Input Image` is connected and `Show Visualization` is enabled, the block returns an annotated image in `Output Image`. Numeric and point results appear on the corresponding outputs based on the operation. ## 📝 Usage Instructions 1. Select the desired operation in `Operation Type`. 2. Connect the required sockets: at minimum connect `Line 1`. Connect `Line 2` or `Anchor Point` where needed by the chosen operation. 3. Optionally provide `Input Image` and enable `Show Visualization` to get an annotated image overlay. 4. Adjust `Offset (px)` or `Interpolation Factor` when using Segment Extraction or Projection operations. 5. Run the scenario; inspect the `Result`, `Point Output` and/or `Extra Output` and view the visual overlay in `Output Image` or with a display block. ## 💡 Tips and Tricks (combining with other blocks) * To get lines from contours or edges automatically, combine with `Find Contour` or `Line Detector` to extract shape/line data and feed the results into `Line Geometry`. * Crop a region and do focused geometry with `Image ROI`, `Image ROI Select` or `Image ROI Polygon` before sending the image to this block — this reduces noise and improves results. * Visualize outputs in the UI using `Show Image` so you can inspect annotated images and interactively verify points and intersections. * If you need to overlay textual results on the annotated image for reports or dashboards, add `Draw Result On Image` after the visualized output. * For measuring distances between detected features, use `Find Contour` or `Feature Detector` to locate points, then use `Line Geometry` to compute midpoints, distances or projections. Feed numeric point outputs to `Measure Position Distance` for additional distance breakdowns. * To isolate only relevant detections before geometry calculations, use `Image ROI Select` or `Check Area (Polygon)` to filter positions and shapes. * When combining detections and tracking workflows, use `Object Detection` or `Object Detection - Custom` upstream to provide coordinates, then use `Line Geometry` for analytics such as intersection checks or approach angle calculations. (hint: use the block outputs like `Point Output` or `Extra Output` as inputs to other processing blocks such as `Measure Position Distance`, `Draw Point` or logging/export blocks.) ## 🛠ī¸ Troubleshooting * If `Output Image` is empty: ensure an `Input Image` is connected and `Show Visualization` is enabled. * If an operation returns no value in `Result` or `Point Output`: check that the required sockets for that operation are connected (for example, `Line 2` is required for angle/intersection operations). * If coordinates seem wrong: verify the coordinate format and that lines are provided as \[(x1, y1), (x2, y2)]. Use preview blocks like `Show Image` or `Draw Point` to inspect intermediate points. * For projection and interpolation results that look off, fine-tune `Offset (px)` and `Interpolation Factor` to match your expected scale and units. If you need step-by-step visual checks, combine the block with `Show Image` and `Draw Point` to validate intermediate geometry before using results downstream. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.augelab.com/function-blocks/detections-shapes/shape-analysis/line-geometry.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.