OPTIONS.md

Command line options

F3D behavior can be fully controlled from the command line using the following options.

Applicative Options

Options	Default	Description
--output=<png file>		Instead of showing a render view and render into it, render directly into a png file. When used with --ref option, only outputs on failure. If - is specified instead of a filename, the PNG file is streamed to the stdout. Can use template variables.
--no-background		Use with --output to output a png file with a transparent background.
-h, --help		Print help and exit. Ignore --verbose.
--version		Show version information and exit. Ignore --verbose.
--readers-list		List available readers and exit. Ignore --verbose.
--config=<config file path/name/stem>	config	Specify the configuration file to use. Supports absolute/relative path but also filename/filestem to search for in standard configuration file locations.
--dry-run		Do not read any configuration file and consider only the command line options.
--no-render		Do not render anything and quit just after loading the first file, use with --verbose to recover information about a file.
--max-size=<size in MiB>	-1	Prevent F3D to load a file bigger than the provided size in Mib, negative value means unlimited, useful for thumbnails.
--watch		Watch current file and automatically reload it whenever it is modified on disk.
--load-plugins=<paths or names>		List of plugins to load separated with a comma. Official plugins are alembic, assimp, draco, exodus, occt, usd, vdb. See usage for more info.
--scan-plugins		Scan standard directories for plugins and display their names, results may be incomplete. See usage for more info.
--screenshot-filename=<png file>	{app}/{model}_{n}.png	Filename to save screenshots to. Can use template variables.

General Options

Options	Default	Description
--verbose=<[debug|info|warning|error|quiet]>	info	Set verbose level, in order to provide more information about the loaded data in the console output. If no level is providen, assume debug. Option parsing may ignore this flag.
--progress		Show a progress bar when loading the file.
--geometry-only		For certain full scene file formats (gltf/glb and obj), reads only the geometry from the file and use default scene construction instead.
--group-geometries		When opening multiple files, show them all in the same scene. Force geometry-only. The configuration file for the first file will be loaded.
--up=<[+|-][X|Y|Z]>	+Y	Define the Up direction.
-x, --axis		Show axes as a trihedron in the scene.
-g, --grid		Show a grid aligned with the horizontal (orthogonal to the Up direction) plane.
--grid-unit=<length>		Set the size of the unit square for the grid. If set to non-positive (the default) a suitable value will be automatically computed.
--grid-subdivisions=<count>		Set the number of subdivisions for the grid.
-e, --edges		Show the cell edges.
--camera-index=<idx>	-1	Select the scene camera to use when available in the file. Any negative value means automatic camera. The default scene always uses automatic camera.
-k, --trackball		Enable trackball interaction.
--animation-autoplay		Automatically start animation.
--animation-index=<idx>	0	Select the animation to show. Any negative value means all animations (glTF only). The default scene always has at most one animation.
--animation-speed-factor=<factor>	1	Set the animation speed factor to slow, speed up or even invert animation time.
--animation-frame-rate=<factor>	60	Set the animation frame rate used when playing animation interactively.
--font-file=<font file>		Use the provided FreeType compatible font file to display text. Can be useful to display non-ASCII filenames.

Material options

Options	Default	Description
-o, --point-sprites		Show sphere points sprites instead of the geometry.
--point-size=<size>	10.0	Set the size of points when showing vertices and point sprites.
--point-type=<sphere	gaussian>	sphere
--line-width=<size>	1.0	Set the width of lines when showing edges.
--color=<R,G,B>	1.0, 1.0, 1.0	Set a color on the geometry. Multiplied with the base color texture when present. Requires a default scene.
--opacity=<opacity>	1.0	Set opacity on the geometry. Multiplied with the base color texture when present. Requires a default scene. Usually used with Depth Peeling option.
--roughness=<roughness>	0.3	Set the roughness coefficient on the geometry (0.0-1.0). Multiplied with the material texture when present. Requires a default scene.
--metallic=<metallic>	0.0	Set the metallic coefficient on the geometry (0.0-1.0). Multiplied with the material texture when present. Requires a default scene.
--hdri-file=<HDRI file>		Set the HDRI image that can be used as ambient lighting and skybox. Valid file format are hdr, exr, png, jpg, pnm, tiff, bmp. If not set, a default is provided.
--hdri-ambient		Light the scene using the HDRI image as ambient lighting. The environment act as a light source and is reflected on the material.
--texture-matcap=<texture file>		Set the texture file to control the material capture of the object. All other model options for surfaces are ignored if this is set. Must be in linear color space.
--texture-base-color=<texture file>		Set the texture file to control the color of the object. Please note this will be multiplied with the color and opacity options. Must be in sRGB color space.
--texture-material=<texture file>		Set the texture file to control the occlusion, roughness and metallic values of the object. Please note this will be multiplied with the roughness and metallic options, which have impactful default values. To obtain true results, use --roughness=1 --metallic=1. Must be in linear color space.
--texture-emissive=<texture file>		Set the texture file to control the emitted light of the object. Please note this will be multiplied with the emissive factor. Must be in sRGB color space.
--emissive-factor=<R,G,B>	1.0, 1.0, 1.0	Set the emissive factor. This value is multiplied with the emissive color when an emissive texture is present.

Window options

Options	Default	Description
--bg-color=<R,G,B>	0.2, 0.2, 0.2	Set the window background color. Ignored if hdri is set.
--resolution=<width,height>	1000, 600	Set the window resolution.
--position=<x,y>		Set the window position (top left corner) , in pixels, starting from the top left of your screens.
-z, --fps		Display a frame per second counter.
-n, --filename		Display the name of the file on top of the window.
-m, --metadata		Display the metadata. Empty without a default scene.
--hdri-skybox		Show the HDRI as a skybox. Overrides --bg-color and --no-background.
-u, --blur-background		Blur background. Useful with a HDRI skybox.
--blur-coc	20	Blur circle of confusion radius.
--light-intensity	1.0	Adjust the intensity of every light in the scene.

Scientific visualization options

Options	Default	Description
-s, --scalars=<array_name>		Specify an array to Color with if present in the file. If no array_name is provided, the first in alphabetical order will be picked if any are available. Requires a default scene. Use --verbose to recover the usable array names.
-y, --comp=<comp_index>	-1	Specify the component from the scalar array to color with. Use with the scalar option. -1 means magnitude. -2 or the short option, -y, means direct values. When using direct values, components are used as L, LA, RGB, RGBA values depending on the number of components.
-c, --cells		Specify that the scalar array is to be found on the cells instead of on the points. Use with the scalar option.
--range=<min,max>		Set a custom range for the coloring by the array. Use with the scalar option.
-b, --bar		Show scalar bar of the coloring by array. Use with the scalar option.
--colormap-file=<name>		Set a colormap file for the coloring. See color maps. Use with the scalar option.
--colormap=<color_list>		Set a custom colormap for the coloring. This is a list of colors in the format val1,red1,green1,blue1,...,valN,redN,greenN,blueN where all values are in the range (0,1). Ignored if --colormap-file option is specified. Use with the scalar option.
-v, --volume		Enable volume rendering. It is only available for 3D image data (vti, dcm, nrrd, mhd files) and will display nothing with other formats.
-i, --inverse		Inverse the linear opacity function used for volume rendering.

Camera configuration options

Options	Default	Description
--camera-position=<X,Y,Z>		Set the camera position, overrides --camera-direction and camera-zoom-factor.
--camera-focal-point=<X,Y,Z>		Set the camera focal point.
--camera-view-up=<X,Y,Z>		Set the camera view up vector. Will be orthogonalized.
--camera-view-angle=<angle>		Set the camera view angle, a strictly positive value in degrees.
--camera-direction=<X,Y,Z>		Set the camera direction, looking at the focal point.
--camera-zoom-factor=<factor>		Set the camera zoom factor relative to the autozoom on data, a strictly positive value.
--camera-azimuth-angle=<angle>	0.0	Apply an azimuth transformation to the camera, in degrees, added after other camera options.
--camera-elevation-angle=<angle>	0.0	Apply an elevation transformation to the camera, in degrees, added after other camera options.
--camera-orthographic		Set the camera to use the orthographic projection.

Raytracing options

Options	Default	Description
-r, --raytracing		Enable OSPRay raytracing. Requires OSPRay raytracing to be enabled in the linked VTK dependency.
--samples=<samples>	5	Set the number of samples per pixel when using raytracing.
-d, --denoise		Denoise the image when using raytracing.

PostFX (OpenGL) options

Options	Description
-p, --translucency-support	Enable translucency support. This is a technique used to correctly render translucent objects.
-q, --ambient-occlusion	Enable ambient occlusion. This is a technique used to improve the depth perception of the object.
-a, --anti-aliasing	Enable anti-aliasing. This technique is used to reduce aliasing.
-t, --tone-mapping	Enable generic filmic Tone Mapping Pass. This technique is used to map colors properly to the monitor colors.

Testing options

Options	Default	Description
--ref=<png file>		Render and compare with the provided reference image, for testing purposes. Use with output option to generate new baselines and diff images.
--ref-threshold=<threshold>	50	Set the comparison threshold to trigger a test failure or success. The default (50) correspond to almost visually identical images.
--interaction-test-record=<log file>		Path to an interaction log file to record interaction events to.
--interaction-test-play=<log file>		Path to an interaction log file to play interactions events from when loading a file.

Rendering options precedence

Some rendering options are not compatible between them, here is the precedence order if several are provided:

• Raytracing (-r)
• Volume (-v)
• Point Sprites (-o)

Options syntax

The --options=value syntax is used everywhere in this documentation, however, the syntax --options value can also be used, with the exception of options that have implicit values, --verbose, --comp and --scalars.

Filename templating

The destination filename used by --output or to save screenshots can use the following template variables:

• {app}: application name (ie. F3D)
• {version}: application version (eg. 2.4.0)
• {version_full}: full application version (eg. 2.4.0-abcdefgh)
• {model}: current model filename without extension (eg. foo for /home/user/foo.glb)
• {model.ext}: current model filename with extension (eg. foo.glb for /home/user/foo.glb)
• {model_ext}: current model filename extension (eg. glb for /home/user/foo.glb)
• {date}: current date in YYYYMMDD format
• {date:format}: current date as per C++'s std::put_time format
• {n}: auto-incremented number to make filename unique (up to 1000000)
• {n:2}, {n:3}, ...: zero-padded auto-incremented number to make filename unique (up to 1000000)
• variable names can be escaped by doubling the braces (eg. use {{model}}.png to output {model}.png without the model name being substituted)

For example the screenshot filename is configured as {app}/{model}_{n}.png by default, meaning that, assuming the model hello.glb is being viewed, consecutive screenshots are going to be saved as F3D/hello_1.png, F3D/hello_2.png, F3D/hello_3.png, ...