Preview Tab Operations

Theoretical Background

The Preview Tab in OrcaSlicer represents the bridge between the digital CAD model (geometric representation) and the physical 3D printing process (machine instructions). Understanding the underlying mechanics of G-code rendering and toolpath generation is critical for preventing print failures before they consume time and material.

G-code Parsing and Re-slicing

When a 3D model is sliced, the geometric mesh is sliced into discrete 2D horizontal layers. The slicer then calculates path vectors within each layer and outputs them as a series of textual commands (G-code). The Preview Tab acts as a G-code parser and visualizer. It reads this raw G-code stream sequentially and reconstructs a 3D model of the toolpaths. The parser translates command coordinates such as: G1 X120.4 Y95.2 Z0.2 E1.45 F4800 into spatial vectors, where:

• G1 represents linear extrusion/movement.
• X and Y define the spatial destination coordinate.
• Z defines the vertical height of the layer.
• E represents the amount of filament extruded.
• F represents the feedrate (linear velocity in mm/min).

By parsing these instructions, OrcaSlicer builds a highly accurate digital twin of the physical extrusion bead.

Preview Workspace Features

The Preview tab is packed with interactive tools, visualization schemes, and diagnostics that allow Krasi to dissect the G-code before exporting it.

The G-code Viewer

To activate the raw text G-code console directly within the Preview workspace, press the "C" keyboard shortcut.

• Synchronized Scrubbing: When the G-code viewer is active, it coordinates in real-time with the horizontal toolpath slider. As you step through the path instructions, the console highlights the exact line of G-code responsible for that motion.
• Auto-Hide Behavior: If the horizontal slider at the bottom is moved all the way to the right (the final G-code instruction of the layer), the G-code console will automatically hide. To bring it back, slide the control slightly to the left.

Legend Color Schemes

Located at the top-left of the Preview viewport is the Legend dropdown. This is your primary diagnostic tool. By changing the visualization scheme, you expose different characteristics of the toolpath: