Orthographic camera instrument

Description

Cornell box rendered with an orthographic camera
scene file

This instrument is an orthographic camera featuring orthographic projection. It provides images similar to a standard rectilinear camera placed very far away, with a very long focal length, or to an object-space telecentric lens. This camera is not physically plausible, as it collects only light coming from a single direction, which means the amount of collected light is zero. This is equivalent to a zero aperture object-space telecentric lens. For this reason, the amount of light collected on the sensor is not in lux.s as with real cameras, but in lux.s/sr (equivalent to cd.s/m² or nits.s). This means that this instrument measures luminance directly and can be used as an exact luminance sensor.

Children nodes

sensor

Sensor : List of channels defined by a sensitivity spectrum

postprocessing

Postprocessing : The post-processing filter chain

Parameters

xresolution

int

Horizontal buffer resolution

yresolution

int

Vertical buffer resolution

pixelfilter

list

The ray pixel filter

shutter

real

Shutter time or exposure

wlmin

real

Low bound of simulation wavelength range (Since Ocean 2014 R2)

wlmax

real

High bound of simulation wavelength range (Since Ocean 2014 R2)

pos

vec3

The camera position : center of pupils apertures, as well as principal points

forwards

vec3

The camera direction (all sampled rays go in that direction). Should be orthogonal to up

up

vec3

The camera up direction. Should be orthogonal to forwards

width

real

The camera field width in meters. Must be greater than 0

height

real

The camera field height in meters. Must be greater than 0

Example

<?xml version="1.0" encoding="UTF-8"?>
<oceanroot version="2.3">
<instrument type="orthocam" name="orthocam">
	<prm xresolution="512" yresolution="512"/>
	<prm pixelfilter="bilinear"/>
	<prm shutter="0.8"/>
	<prm wlmin="380E-9"/>
	<prm wlmax="780E-9"/>
	<prm pos="0.278 0.273 -0.8"/>
	<prm forwards="0 0 1"/>
	<prm up="0 1 0"/>
	<prm width="0.6"/>
	<prm height="0.6"/>
	<sensor type="ciexyz" name="sensor"/>
	<postprocessing type="" name="postprocessing">
		<filter type="xyztorgb" name="filter1" enabled="1" xwhite="0.3127" ywhite="0.329"/>
	</postprocessing>
</instrument>
</oceanroot>

See also

Instrument types