Orthographic camera

Description

../../../_images/orthocam.jpg

Cornell box rendered with an orthographic camera

Instrument 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). This means that this instrument measures luminance directly and can be used as an exact luminance sensor.

Children Nodes

This node may have a variable number of output children with custom names.

Sensor sensor

List of channels defined by a sensitivity spectrum

Output user-defined

First output preset

Output user-defined

Second output preset

Output user-defined

Parameters

name

type

description

xresolution

integer

Horizontal buffer resolution

yresolution

integer

Vertical buffer resolution

pixelfilter

list

The ray pixel filter

shutter

real

Shutter time or exposure, in seconds

wlmin

real

Low bound of simulation wavelength range

wlmax

real

High bound of simulation wavelength range

pos

vec3

The camera position : center of 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

Ocean XML 5.0 example

<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"/>
     <output type="rgbimage" name="linearimage">
             <prm colorspace="srgb"/>
             <prm depth="8"/>
             <prm xwhite="0.31271"/>
             <prm ywhite="0.32902"/>
             <prm hcc="0.32"/>
             <prm drawinfo="false"/>
     </output>
</instrument>