Camera & Viewport Settings

Camera & Viewport Settings

OxyBrush features a dedicated real-time viewport renderer built with wgpu. This guide explains camera controls, field of view, matcaps, cavity shading, ambient occlusion, and display options designed specifically for sculptors.

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Camera Projections & Field of View

OxyBrush supports both perspective and orthographic camera projections.

Perspective vs Orthographic

• Perspective Projection (NumPad 5): Simulates natural human vision and physical camera lenses. Essential for character portraits, concept design, and proportional accuracy.
• Orthographic Projection (NumPad 5): Eliminates perspective foreshortening. Lines parallel in 3D remain parallel on screen. Ideal for architectural sculpting, hard-surface modeling, and matching reference background sheets.

Field of View (FOV)

Adjust FOV in the Viewport Settings panel:

• Default (45° - ~50mm lens): Natural perspective with minimal distortion.
• Portrait (25° - ~85mm lens): Flattens facial features slightly, avoiding wide-angle distortion (like large noses) when sculpting heads.
• Wide Angle (75° - ~24mm lens): Dramatic cinematic angles and wide panoramas.

Camera Orbit Pivots

By default, the camera orbits around the geometric center of the active mesh piece. You can re-center the orbit pivot at any time:

• Press NumPad . (Period) or F while hovering over a specific part of the mesh to center the camera pivot directly onto the vertex beneath your mouse pointer.

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Shading & Material Modes

Sculptors need clear visualization of form, surface tension, and silhouette without complex lighting setups. OxyBrush provides dedicated shading modes accessible from the Display panel:

1. Matcaps (Material Capture)

Matcaps project pre-baked lighting, shadows, and reflections from spherical 2D images onto the mesh using view-space normals.

Built-in Matcaps:

• Clay Red / Terra Cotta: Classic warm sculpting clay that makes surface planes and volumes easy to read.
• Neutral Grey: Balanced medium grey with soft specular highlight; ideal for checking subtle undulations.
• Pearl White: High specular response that clearly exposes pinched or irregular topology.
• Dark Chrome / Metal: Sharp anisotropic reflection for checking surface curvature continuity (reflection zebra lines).
• Chalk / Matte: Zero specular diffuse shading for soft organic modeling.
• Silhouette (Flat Black): Renders the mesh in pure solid black against the background to evaluate character silhouettes.

Loading Custom Matcaps: You can load any standard 512x512 or 1024x1024 matcap PNG texture:

1. Go to the Materials tab on the right sidebar.
2. Under Matcap, click Import Custom Matcap....
3. Select your .png or .jpg file. Custom matcaps are saved in your user assets folder for future sessions.

2. Cavity Shading

Cavity shading detects surface curvature and deep valleys:

• Cavity Intensity: Darkens sharp crevices, wrinkles, pores, and seams.
• Peak Highlight: Lightens high ridges and sharp apexes.
• Tip: Cavity shading makes micro-details visible even under low-contrast matcaps.

3. Screen-Space Ambient Occlusion (SSAO)

Real-time ambient occlusion adds soft contact shadows in deep corners, under armpits, between fingers, and inside mouth cavities.

• Adjustable Radius and Intensity sliders in the Viewport panel.
• SSAO runs asynchronously with negligible performance overhead.

4. Flat vs Smooth Shading

• Smooth Shading (Default): Interpolates normals across polygons for organic sculpting.
• Flat Shading: Renders each polygon face with its true geometric face normal. Crucial when checking low-poly blockouts or inspecting planar cuts made with the Flatten or Trim brushes.

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Viewport Overlays & Guides

Customize visual helpers to suit your workflow:

Overlay	Hotkey	Description
Wireframe Overlay	Shift + W	Displays the polygon mesh edges over the shaded surface. Slider adjusts wireframe opacity.
Symmetry Plane	Alt + X	Displays a semi-transparent mirror plane slicing through the symmetry axis.
Floor Grid	Toggle in Display panel	Renders a reference 3D ground grid with metric unit markings.
World Axis Triad	Viewport corner	Visualizes the red (X), green (Y), and blue (Z) global coordinate axes.
Polycount HUD	Bottom status bar	Displays active vertex count, triangle count, current subdivision level, and render FPS.

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High-Performance Viewport Options

For complex scenes with millions of triangles, OxyBrush includes dedicated performance settings in Settings > Performance:

• Zero-Copy Index Buffers: Re-uploads only modified index chunks rather than whole mesh buffers.
• Parallel GPU Mesh Rebuild: Uses Rayon multithreading across CPU cores to pack vertex and normal streams before pushing to VRAM.
• Dab Budget Per Frame: Caps the maximum number of brush dabs calculated per frame during ultra-fast pen sweeps to preserve a solid 60+ FPS without stroke skipping.