Documentation

Orthographic Views & Section Drawings

Snap the 3D camera to standard top, front, side, or back orthographic views, and generate scaled IFC-direct section drawings with line-weight hierarchy and material hatching.

Orthographic Views & Section Drawings

Orthographic views snap the camera to a standard axis-aligned position — looking straight down for a plan view, straight forward for a building cross-section, or sideways for an elevation. The perspective camera is preserved; the view simply animates to the new angle. This is the fastest way to read a floor plan when the corresponding PDF isn't open, and the foundation for generating scaled section drawings.

The six preset views

Key / Control	Action
Top View	Look straight down — plan view
Bottom View	Look straight up — reflected-ceiling-plan angle
Front View	Look at the building from the front — elevation
Back View	Look at the building from the back — back elevation
Left View	Look from the left side — side elevation
Right View	Look from the right side — opposite side elevation

Open from View → Top View (and equivalents) or from the orthographic view picker in the 3D viewer's top overlay. Every snap is a 600 ms smooth animation so you don't lose spatial orientation.

Tip: Top View paired with a Section Box on the Z axis is the fastest way to look down through a single floor — combine the two when the PDF for that floor isn't loaded yet.

Generating a scaled section drawing from the view

Once you have the camera at the angle you want, use File → Export Section as PDF to generate a scaled orthographic drawing. Pick the cut depth (how far behind the camera plane to draw), the sheet scale (1:50, 1:100, 1:200, custom), and the line-weight convention (cut/visible/hidden), then export to PDF. The output is a calibrated drawing you can mark up immediately with the full LocusBIM toolset — no separate calibration step required.

Line weights matter

The biggest visual difference between a section drawing that looks like a real drawing and one that looks like wireframe junk is line-weight hierarchy:

Key / Control	Action
Cut edges (at the cut plane)	0.5 mm solid — thickest
Visible edges (in front of cut)	0.25 mm solid
Hidden edges (behind cut, within depth)	0.13 mm dashed
Centrelines (cylindrical elements)	0.13 mm chain-dashed

LocusBIM's defaults follow ISO 128-50 / ANSI Y14.2. You can override per category — for example, push all mechanical-discipline edges to a heavier weight if the section is intended for MEP coordination.

IFC-direct material hatching

Cut elements get a hatch fill identifying their material. LocusBIM reads the IFC material classification (IfcMaterial, IfcMaterialLayerSet) and applies hatch patterns from the bundled library — concrete diagonal, steel solid black, masonry hatched, insulation wavy. If the IFC lacks material data (common on models exported from non-Revit authoring tools), the fill defaults to neutral grey so the cut is visible without making false claims about material.

Tip: For a deeper walkthrough of when IFC-direct section generation is the right workflow (vs going through Revit), see the blog post How to generate 2D orthographic sections directly from 3D IFC models.