<a name="1008403"> </a>As you paint with the Image Hose, Corel Painter selects images from the nozzle file based on one or more rules. This selection process is known as indexing. This indexing determines which images from the many in the nozzle file are delivered from the Image Hose. The Image Hose settings in the Stroke Designer let you change the rules for indexing the images.
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<p id="1008430" class="Body">
<a name="1008430"> </a>Image nozzle files can be created with one, two, or three image progressions known as "ranks." Corel Painter offers these three rankings, so each nozzle file can be identified as a 1-Rank, 2-Rank, or 3-Rank nozzle.
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<p id="999166" class="Body">
<a name="999166"> </a>The following indexing factors are available in Corel Painter:
<li class="SmartList1"><a name="1008597"> </a>The Rank 2 and Rank 3 types have no effect on a 1-Rank nozzle. The rank types are described below.</li>
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<a name="999192"> </a>Rank Types
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<p id="1001301" class="Body">
<a name="1001301"> </a><span style="color: #000000; font-style: normal; font-weight: bold; text-decoration: none; text-transform: none; vertical-align: baseline">Sequential</span> indexes images in the order they appear in the rank-moving left to right, and top down, just as you read English.
<a name="1001315"> </a><i>Above: sequential indexing. Below: random indexing.
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<p id="999205" class="Body">
<a name="999205"> </a><span style="color: #000000; font-style: normal; font-weight: bold; text-decoration: none; text-transform: none; vertical-align: baseline">Random</span> selects images from the rank at random.
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<p id="999206" class="Body">
<a name="999206"> </a>Randomness can add irregularity of color and texture to the areas you paint with the Image Hose. This contributes to the aesthetics of the painting because minor irregularities occur in natural structures.
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<p id="1001344" class="Body">
<a name="1001344"> </a><span style="color: #000000; font-style: normal; font-weight: bold; text-decoration: none; text-transform: none; vertical-align: baseline">Source</span> delivers images based on the luminance of pixels in the clone source (or current pattern if you have not set a clone source). The pixels of the working document have a direct correspondence with the pixels of the clone source image. As the luminance increases, Source delivers images from later in the rank.
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<p id="1001681" class="Body">
<a name="1001681"> </a>For best results, the clone source should have the same dimensions as the document in which you're working. For more information on setting up and using a clone source, refer to <a href="11-Cloning6.html#1005675">"Changing Clone Source"</a>.
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<p id="999231" class="Body">
<a name="999231"> </a>Depending on the nozzle you're using, Source can be quite useful. For example, if the source image is black on the left and progresses through gradations to white on the right, the Image Hose delivers images from the start of the rank at the left of the document, in the dark area. As the brush moves to the right into the lighter area, the Image Hose delivers images from later in the rank.
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<p id="999233" class="Body">
<a name="999233"> </a>To take advantage of this feature, you may want to create a special source image for the single purpose of controlling the Image Hose.
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<p id="999234" class="Body">
<a name="999234"> </a>The clone source image or pattern for controlling the Image Hose may be grayscale. Remember, Corel Painter uses only the luminance values.
<a name="1005069"> </a><i>Indexing based on Source.
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<p id="999240" class="Body">
<a name="999240"> </a><span style="color: #000000; font-style: normal; font-weight: bold; text-decoration: none; text-transform: none; vertical-align: baseline">Bearing</span> indexes images based on the position of the stylus. Not all stylus models convey this information. This control does not work with a mouse.
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<p id="999243" class="Body">
<a name="999243"> </a><span style="color: #000000; font-style: normal; font-weight: bold; text-decoration: none; text-transform: none; vertical-align: baseline">Tilt</span> indexes images based on the tilt of the stylus. Not all stylus models convey this information. This control does not work with a mouse.
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<p id="999246" class="Body">
<a name="999246"> </a><span style="color: #000000; font-style: normal; font-weight: bold; text-decoration: none; text-transform: none; vertical-align: baseline">Pressure</span> indexes images based on stylus pressure. Greater pressure selects images from later in the rank. Pressure works only with pressure-sensitive tablets.
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<p id="999247" class="Body">
<a name="999247"> </a>Pressure is a great control for requesting images from a nozzle. For example, if you set up your nozzle file to progress from small to larger images, heavier strokes deliver larger images.
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<p id="999250" class="Body">
<a name="999250"> </a><span style="color: #000000; font-style: normal; font-weight: bold; text-decoration: none; text-transform: none; vertical-align: baseline">Direction</span> indexes images from the rank based on the direction of the stroke. The first item in the rank matches to a left-right stroke (toward 3 o'clock). As the stroke direction progresses counter-clockwise, the Image Hose delivers subsequent images from the rank.
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<p id="999259" class="Body">
<a name="999259"> </a>The number of elements in the rank determines the directional change required to index a different element. For example, a nozzle file that contains 72 images at progressive angles delivers a different item at every 5░ of stroke direction (360░/72=5░).
<a name="1005097"> </a><i>This Arrow nozzle is an example of indexing based on Direction.
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<p id="999263" class="Body">
<a name="999263"> </a><span style="color: #000000; font-style: normal; font-weight: bold; text-decoration: none; text-transform: none; vertical-align: baseline">Velocity</span> indexes images from the rank based on the speed of the stroke. A faster stroke delivers elements from later in the rank. Velocity is often used with a mouse to mimic pressure.
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<p id="999264" class="Body">
<a name="999264"> </a>Velocity can be difficult to control. For this reason, you might want to use it in a rank with few elements.
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<p id="999267" class="Body">
<a name="999267"> </a><span style="color: #000000; font-style: normal; font-weight: bold; text-decoration: none; text-transform: none; vertical-align: baseline">None</span> returns one element only- the last in the rank.
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<h3 id="999268" class="Heading2">
<a name="999268"> </a>Nozzle Options
</h3>
<p id="999269" class="Body">
<a name="999269"> </a>The Nozzle Selector has one option for the Image Hose-Use Brush Grid.
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<p id="1001390" class="Body">
<a name="1001390"> </a>When Use Brush Grid is enabled, the Image Hose places images in a regular grid pattern. The grid size follows the grid in the nozzle file.
