2009

Table Of Contents
2. Click Delete to delete the light from the palette. This will also remove the light from the scene.
3. Click Copy to copy the light to the clipboard. Right-click an empty space in the palette and click
Paste to paste a copy of the light with the same name suffixed with the next number in the list.
4. Click Rename to rename the light. You can also select the light and press F2 to rename it.
5. Click Clear Palette to delete all the lights from the palette and hence from the scene.
6. Click Edit or simply double-click a light to open the Light Editor dialog box, allowing you to edit its
parameters. See Editing Lights for more information on this.
Editing Lights
You can edit a light in the palette by double-clicking it, or right-clicking and choosing Edit on the shortcut
menu.
There are six types of light visible in both OpenGL interactive renders and photorealistic renders:
1. Ambient lights give a general background light to the scene and therefore only have intensity and
color parameters.
2. Eye lights are located at the viewpoint and also only have intensity and color parameters.
3. Point lights have a location but shine in all directions. They also have an intensity and color and
additionally can cast shadows (only available in a full photorealistic render).
4. Distant lights are directional and so have a location and target. However, the location and target
merely set up an axis down which the light shines, as these light types are infinitely far away and
their beams are parallel. As well as intensity and color parameters, they can also cast shadows in a
photorealistic render.
5. Spot lights are also directional and therefore have a location and target, as well as intensity, color
and shadow parameters. In addition, they also have parameters for affecting the light's fall off and
cone angle, as these light types are not infinitely far away, so do spread their light over a cone and
the intensity does diminish away from the light.
6. Sun simulates the sun's light. The orientation of your model is defined by north and up directions.
The position of the sun is specified as azimuth and altitude. If the sun's mode includes "Position", you
can input your location on earth, the time (using local time zone) and date and Presenter will
calculate the sun's azimuth and altitude for you. If the sun's mode includes "Intensity", Presenter will
also calculate an accurate intensity for the sun based on position, time of year and atmospheric
conditions.
There are an additional three types of light visible only in photorealistic renders:
1. Projector lights are used to project an image onto surfaces. You can define the file of the image to
be projected.
2. Sky simulates the illumination from the sky (but not the direct contribution due to the sun itself). The
orientation of your model is defined by north and up directions. The position of the sun is specified as
"sun altitude" and "sun azimuth". Whilst the direct contribution of the sun is not included, its location
will determine the appearance of the sky hemisphere. If the intensity is left at 0, Presenter will
Presenter Lighting
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