NAME col_legend2 AUTHORS Konstantinis G. Kakoulis and Yihsing Song, under the supervision of Dr. Susanna Wei, Department of Mathematics and Computer Science, Saint Joseph's University, Philadelphia, Pennsylvania. ACKNOWLEDGEMENT This module is a modification of the color legend module by Lawrence Berkeley Laboratory. The modification includes: 1. An added input port of type FIELD 1D; The minimum value, maximum value and the visibility of the color legend are defined by the first, second, and third element of the field, respectively. 2. Two additional parameters: a. LEGEND WIDTH, defines the width of the color legend. b. LEGEND HEIGHT, defines the height of the color legend. 3. The geometry produced by the module is NOT TRANSFORMABLE. 4. The first and the last labels of the color legend are not displayed on the screen. SUMMARY Name col_legend2 Type mapper Inputs colormap Inputs Field 1D Output geometry Parameters Name Type Default Min Max ----- ---- ------- --- --- Boundary On/Off boolean on Boundary Gray Level integer 255 0 255 Legend Width real 0.08 0.01 1.0 Legend Height real 1.61 0.01 3.5 Labels On/Off boolean on Label Density integer 12 12 12 Label Height real 0.09 0.001 0.2 Label Gray Level integer 255 0 255 Label Font integer 0 0 21 Label Boundaries On/Off boolean Reverse Colors boolean off Legend Orientation radio vertical vertical horizontal DESCRIPTION This module takes an input colormap and generates a "color legend," consisting of a number of geometric objects which may be subsequently rendered using the render geometry module. The range of colors in the color scale is controlled by the input field 1D All colors in the colormap are represented in the output color scale. In addition to the smoothly shaded "color bar", the user may control various parameters relating to labeling characteristics and legend orientation. The color legend is not transformable and the visibility of the color legend is controlled by the input field 1D. INPUTS AVS Colormap (required) Field 1D (required) PARAMETERS X offset Y offset Define the position of the color legend. Width Height Define the size of the color legend Boundary On/Off This boolean flag indicates whether the "color bar" part of the color legend is to have, on its perimeter, a pixel-thick line "boundary." The boundary is useful, especially if many colors in the "color bar" are similar to the current background color. Boundary Gray Level This value is used to set the gray level of the boundary. A value of 0 corresponds to a black boundary, while a value of 255 corresponds to a white boundary. Labels On/Off This boolean value is used to enable/disable the annotation which accompanies the color legend which indicate the values associated with the colors. Label Density The number of labels produced is controlled through this parameter. The minimum is two (the top and bottom of the color bar), and the maximum is twelve. The max of 12 was an arbitrary decision based upon the "busyness" of color legends with too many labels. Feel free to change this. Label Height This slider controls the size of the font. The number associated with this slider is in some arcane coordinate system. Label Gray Level Controls the gray level of the labels text (and the labels boundary, as well). A value of 0 will produce black text, a value of 255 will produce white text. Label Font Selects from one of 22 fonts. Whether or not all of these fonts actually exist on your system is open for debate. The number of available fonts comes from the Stardent documentation. Label Boundaries On/Off Controls whether or not a "boundary line" appears in the color bar at the location corresponding to a particular label. So, for example, if only two labels are specified, the two boundaries will be draw at the top/bottom of the colormap. No boundaries will be visible (unless the gray level is different than that for the "regular" boundary) unless the label density parameter is set to three or higher. Reverse Colors This flag will reverse the colors, and any associated labels. Legend Orientation The user can choose between a vertical or horizontal color legend orientation. OUTPUTS AVS geometry. EXAMPLE generate colormap | color scale | render geometry | display pixmap LIMITATIONS It is possible to produce a really messy color legend by fiddling with the parameters enough. There is no "title" parameter. This has been specifically omitted as it would be impossible to appease all users as to its location with respect to the color legend. The positioning of the labels with respect to the color legend is fixed: on vertical legends, the characters appear to the right, and on horizontal legends, they appear below the legend (compare with the NCAR utility for producing legends).