BRL-CAD Renderer Showcase

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RT lighting models
RT output options
Edges and line renderers
Scalar image renderers

This gallery shows BRL-CAD’s image-producing ray-tracing front ends and selected rt output styles rendered against the sample Cornell box model. Each snapshot uses the same database, object, perspective, and saved view matrix from db/cornell.rt:

rt -B -M -p55 -s512 -P1 [style options] -o <name>.png cornell.g all.g < cornell.view

The scalar and plot outputs are converted with BRL-CAD image tools. In particular, rthide is rendered as plot3 and rasterized with plot3-fb and fb-png.

Note	This article and its images are a committed snapshot. Developers can regenerate them from the built tools by configuring with `-DBRLCAD_GENERATE_RENDERER_GALLERY=ON` and building the `renderer-gallery-snapshot` target.

RT lighting models

rt_l0

rt -l0 full lighting: Full lighting model with explicit Cornell-box light, material color, shadows, and reflection.

rt_l1

rt -l1 eye diffuse: Simple diffuse lighting from the eye, useful for debugging object form without scene-light complexity.

rt_l2

rt -l2 normals: Surface normals encoded as RGB colors, useful for checking orientation and curvature continuity.

rt_l3

rt -l3 three-light: Three-light diffuse debug model. On the Cornell box this currently matches the full-lighting snapshot closely.

rt_l4

rt -l4 curvature: Inverse-curvature debug display. The Cornell box is mostly planar, so the committed image is intentionally flat.

rt_l5

rt -l5 principal direction: Principal curvature direction debug display.

rt_l6

rt -l6 UV: UV coordinate test-map style; U appears in red and V in blue.

rt_l7

rt -l7 photon map: Photon-mapping global illumination using a small deterministic photon count so regeneration remains quick enough for documentation snapshots.

rt_l8

rt -l8 heat graph: Heat-graph diagnostic mode maps the high-resolution current-thread CPU time needed to render each fully shaded pixel to grayscale; brighter pixels took longer to render.