"No one can be told what GeeXLab is, you have to see it for yourself!"

"Stop Playing Games and Start Making Them! With GeeXLab, your are on your way!"

Quick Links
What is GeeXLab
Download GeeXLab
GeeXLab Requirements
Online Help
Articles and Tutorials
Samples Screenshots
Videos

GeeXLab Changelog

XML Ref. Guide
Scripting Ref. Guide
Code Samples

Purchase GeeXLab
GeeXLab SDK

Shader Library

Follow GeeXLab's News

Subscribe to GeeXLab news by email

[ Back to Geeks3D.com ]

GeeXLab

Laboratory for Real Time 3D Programming (prototyping and demos)
OpenGL, Lua, Python, GLSL,
PhysX and more...

Reference Guide
XML Nodes

ť Back to homepage
ť Back to Developer's Guide Index

<light> XML Node

XML Node Summary

<light
  name=""
  type=""
  render="FALSE"
  display_tripod="FALSE"
  auto_update_direction="FALSE"
  constant_att="1.0"
  linear_att="0.0"
  quadratic_att="0.0"
  spot_angle="30.0"
  shadow_emitter="FALSE"
  >
  <ambient
    r="0.2"
    g="0.2"
    b="0.2"
    a="1.0"
    >
  </ambient>
  <diffuse
    r="1.0"
    g="1.0"
    b="1.0"
    a="1.0"
    >
  </diffuse>
  <specular
    r="0.6"
    g="0.6"
    b="0.6"
    a="1.0"
    >
  </specular>
  <position
    x="0.0"
    y="200.0"
    z="200.0"
    >
  </position>
  <orientation
    pitch="0.0"
    yaw="0.0"
    roll="0.0"
    >
  </orientation>
  <lookat
    x="0.0"
    y="0.0"
    z="0.0"
    w="1.0"
    >
  </lookat>
  <camera_params
    fov="110.0"
    aspect="1.0"
    znear="1.0"
    zfar="100.0"
    >
  </camera_params>
</light>

<light>

Description
The light node is the object which makes it possible to represent a dynamic light. In the case of a dynamic light, lighting calculations are completely processed at each frame and for each object that has its lighting state set to TRUE. Thus, the more lights there will be, the longer will be the calculations and the more the FPS will decrease. The maximum number of dynamic lights is limited by the hardware. They are generally eight.

light element has 10 attributes and 7 sub-element(s)

Attributes

name [STRING]: Name of the light object
type [STRING]: Light'stype: omnidirectional, directional or spot. - Values = OMNI | DIRECTIONAL | SPOT
render [BOOLEAN]: Enables or disables the rendering of the light position (omni light). - Default value = FALSE - Values = TRUE|FALSE
display_tripod [BOOLEAN]: Displays or hides light's tripod. - Default value = FALSE - Values = TRUE|FALSE
auto_update_direction [BOOLEAN]: Enables or disables the automatic update of the tripod's direction (Z axis). - Default value = FALSE - Values = TRUE|FALSE
constant_att [REAL]: Specifies the constant attenuation factor of the light with the distance (more precisely, the distance between the light position and a vertex). - Default value = 1.0
linear_att [REAL]: Specifies the linear attenuation factor of the light with the distance. - Default value = 0.0
quadratic_att [REAL]: Specifies the quadratic attenuation factor of the light with the distance. - Default value = 0.0
spot_angle [REAL]: Sets the aperture angle of light's cone. - Default value = 30.0
shadow_emitter [BOOLEAN]: The light is a source of shadow or not. - Default value = FALSE - Values = TRUE|FALSE

Code sample :

<ambient>

Description
Sets the light's ambient color.

ambient element has 4 attributes and 0 sub-element(s)

Attributes

r [REAL]: red channel - Default value = 0.2
g [REAL]: green channel - Default value = 0.2
b [REAL]: blue channel - Default value = 0.2
a [REAL]: alpha channel - Default value = 1.0

<diffuse>

Description
Sets the light's diffuse color.

diffuse element has 4 attributes and 0 sub-element(s)

Attributes

r [REAL]: red channel - Default value = 1.0
g [REAL]: green channel - Default value = 1.0
b [REAL]: blue channel - Default value = 1.0
a [REAL]: alpha channel - Default value = 1.0

<specular>

Description
Sets the light's specular color.

specular element has 4 attributes and 0 sub-element(s)

Attributes

r [REAL]: red channel - Default value = 0.6
g [REAL]: green channel - Default value = 0.6
b [REAL]: blue channel - Default value = 0.6
a [REAL]: alpha channel - Default value = 1.0

<position>

Description
Sets light's position in local space (relative position).

position element has 3 attributes and 0 sub-element(s)

Attributes

x [REAL]: x coordinate - Default value = 0.0
y [REAL]: y coordinate - Default value = 200.0
z [REAL]: z coordinate - Default value = 200.0

<orientation>

Description
Sets light's orientation in local space (relative orientation).

orientation element has 3 attributes and 0 sub-element(s)

Attributes

pitch [REAL]: rotation in degrees around X axis - Default value = 0.0
yaw [REAL]: rotation in degrees around Y axis - Default value = 0.0
roll [REAL]: rotation in degrees around Z axis - Default value = 0.0

<lookat>

Description
Sets light's lookat direction/point for shadow mapping.

lookat element has 4 attributes and 0 sub-element(s)

Attributes

x [REAL]: x coordinate of direction/point lookat - Default value = 0.0
y [REAL]: y coordinate of direction/point lookat - Default value = 0.0
z [REAL]: z coordinate of direction/point lookat - Default value = 0.0
w [REAL]: w coordinate of direction/point lookat. If w=0.0, lookat is a direction vector and if w=1.0, lookat is a point. - Default value = 1.0