Drawings are made up of points, lines and areas that are drawn in a "connect the dots" fashion between exact coordinates. The appearance of drawings is highly dependent on the formatting choices used to draw the points, lines and areas. Drawings may be formatted to provide a particular appearance, or a theme can be created for a drawing that shows that drawing using desired formatting.
The main formatting choices are:
The color of solid points and lines and the foreground color of two-color area styles or of two-color area border styles. Choosing a transparent color for foreground color for an area will turn off display of that area. This is a short-cut way of turning off areas when desired.
The fill color in most styles used for points, lines, areas and area borders.
The pattern or icon used to draw points, lines, areas or area borders.
The relative size to use for patterns used to draw points, lines, areas and area borders. Does not apply to bitmapped images used for points.
Allows rotating the symbols used for points to a given angle.
The Format toolbar for drawings shows the basic formatting choices in use for the active drawing or drawing layer in a map.
It shows foreground color, background color, style and size currently in use for areas, area borders, lines and points as well as the point rotation angle button for points. Default formatting uses light gray for background colors with black used for foreground color for lines and points and dark gray used as the foreground color for areas. Changes made in this toolbar will immediately be applied to the drawing. Drawings (and thus drawing layers in maps) have one set of formats for all areas, lines and points in that drawing. The format toolbar always shows the formats in use for the active layer or drawing.
To Change Formatting
1. Click on the layer tab that contains the objects.
2. Click on the format control to be changed (colors, style or size) for the type of object to be changed (areas, lines or points).
Click on the foreground or background color wells in the format toolbar to change color.
The color wells display knows what the current color is and will display a sample of color wells that Manifold reckons will be helpful. The screen shot above shows that the current color is a bright blue (indented well). The top line will always show lightness variations of the current color. The second line in the color wells display will show grayscale variations. The X color well in the upper right is transparent color. Using that color will result in transparency everywhere the color is used.
The rest of the color wells pane shows a range of colors beginning with blues and greens and ending with reds. Scroll down using the down arrow at the side of the pane.
Press Theme to invoke thematic formatting. Press More to open the standard Windows color-picking dialog.
This example shows changes to area formats, line formats and point formats. Area border formatting will not be changed in this example.
We begin with a map of California containing four layers:
· CA areas contains areas showing the land regions of California
· CA hydro contains lines showing various hydrological (water) features.
· CA roads contains lines showing main roads.
· US towns contains points showing the center points of populated places with populations above 20000.
In this example map, all of the layers contain one type of object (areas, lines or points) only. In the illustration above, the CA areas layer is the active layer so the format toolbar shows the formats for that layer (all default settings). Even though the CA areas layer contains areas only, the lines and points format controls are enabled so we can set values that will be used for any lines or points that might be created in this layer. The illustration is zoomed into the southern part of San Francisco Bay, into the heartland of Silicon Valley.
To change the color of the areas in the CA areas layer, we click into the background color well for areas and change the color. Let's change it to a khaki green color. All areas in the layer will instantly change background color. Note that the default area pattern draws the edges of areas with a pixel of foreground color, which remains the default dark gray.
Let's make the water features blue. These are located in the CA hydro layer so we click the CA hydro tab to make this layer the active layer. As we click the CA hydro tab, the format toolbar will switch to show the settings for this layer. We haven't changed anything in this layer so it still shows the default settings. For example, note that the area background color shows the default gray color since in this layer (unlike the CA areas layer used in the previous illustration) we have changed the area background color.
Solid lines are drawn in foreground color, so we click into the foreground color well for lines and change the color to a bright blue. Instantly, all lines in this layer will change to blue color. Note that this change affects lines only in this layer. Road lines, for example, are not changed when we change the formatting of the CA hydro layer.
To change the format of road lines, we click the CA roads tab. The format bar changes to show the formats for this layer, which are still the default settings.
Let's make the road lines a dark green. We do this by clicking on the foreground color well for lines and changing the color to dark green.
If we want the road lines to be less visually apparent, we can change them to a dashed line style by clicking into the style well for lines and choosing a dashed pattern. The dashed pattern we chose uses foreground color for the dark bits and background color for the light bits. If we choose the same color as was used for the areas in CA areas for the background color for our lines, they will appear to be dashed segments.
A better way of achieving this same effect is choosing transparent color for the background color; that is, to use no color (for complete transparency) for the background color of lines. Click on the transparent color well at the upper right of the main palette to chose transparent color.
If we chose transparent color for the background color, the alternate segments of the dashed line style would be transparent. This would avoid the unpleasant effect seen above where the road lines cross San Francisco Bay but still have the light green background color in alternate dashes. Had we used transparent color the white color of the bay's background would have been visible through alternate dashes and thus the dashed line effect we seek would be preserved no matter what color background.
We now click the US towns layer tab to set it active. This layer still uses default formatting as the format toolbar shows.
We can make the points in this layer instantly more visible by changing the background color for points (the fill color) to bright yellow.
Clicking into the style box for points and choosing a square changes the points to square boxes. Increasing the size parameter to 10 makes the boxes larger.
Changing line or area format settings for the US towns layer will have no visual effect, since there are no objects in this layer except points. However, if we would like to set formatting to be used for any area or line objects that might be created or moved into this layer we can do so. In the illustration above, we have changed the area colors to a black foreground color and a brick-red background fill color.
If we now use the Shapes toolbar to draw an area in the US towns layer it will be drawn using the new format colors specified for areas in this layer. In the illustration above, we have drawn a circular area centered on the Gordon Biersch brewery restaurant in Palo Alto. This is a somewhat contrived example, since it is poor organization to mix different conceptual things (center points of towns as well as areas showing different types of zones of interest) in the same layer.
Finally, if we click back on the CA hydro layer, note that none of the formatting changes made to other layers has applied to this layer. It still retains default formatting for areas and points, with the only change being the use of bright blue color as the foreground color for lines. Changes made with the format toolbar apply only to the active layer.
Points and Lines in the Same Layer
Drawings are often imported from GIS formats intended for use in maps where the roads might be used for transportation network analysis. In such cases the map of roads is drawn as a network with point objects located at the ends of each line. This is done because mathematically a network is defined by points (nodes) and not the lines (links) between them.
When imported into Manifold, such road drawings will appear in default formatting. Because default formatting uses a size of 3 for points, the roads will have lots of "bubbles" throughout. Changing this is easy.
Simply click on the size well for points and change the size to 1. A size of one draws each point symbol as a single printer's point in size, so the points will blend into the default size of lines.
The above is a quick means of dealing with the visual appearance of the drawing, but it still leaves the points in the same layer as the lines. If we change line colors or size, we will have to remember to change those parameters for the points as well if we want the points to continue to appear blended in with the lines. A better idea is to select all the points in this layer and to move them to their own layer. We can then turn that layer off and on at will whenever we want to see the network node points. Should we want to do transportation network analysis, we can select the lines and points to be used as a network. Manifold has no problem working with nodes and links that are in separate layers.
Thematic formatting is the use of a controlling data field to automatically vary the color, style or size of objects. For example, we might vary the size of points showing cities based on a population field for each point. Cities with greater populations would be shown as larger points.
See the Thematic Formatting topic for more information.
See the Color topic for fast "four-color" coloring of drawings.
Themes and Drawings
It's frequently the case that we would like to format the same drawing in several different ways. Manifold allows us to create themes to show the same drawing using different formatting characteristics. Themes require no extra storage because they do not duplicate the drawing, they simply show the same drawing using different formatting, such as different background or foreground colors. See the Themes topic for details.
· The most common formatting error when formatting layers in maps is to lose track of which layer contains which objects. The best way to avoid this is to name layers in a sensible way ("Roads," "Streams" and so on) so that it's obvious which objects are in which layers. If we lose track anyway, we can always see which objects are in a particular layer by double clicking the layer tab to turn it OFF and ON. It will be immediately obvious which objects are in that layer as they turn OFF and ON.
· If one wishes to uses hundreds of formats in a map to show the same drawing in hundreds of different ways, doing so is perfectly possible. To do so, we create as many themes for the subject drawing as desired.
· To have a different visual appearance for objects in the same layer, use Thematic formatting. This assures there is some guiding pattern to the different colors or other format attributes.
· The hydrography lines in the California map example do not line up perfectly with the edges of areas because they were taken from two different data sets. The hydrography lines are from the 1:2M-scale USGS DLG map series while the CA areas layer was created using NOAA 1:100K-scale shorelines data.
· See www.gordonbiersch.com for more on where to find real beer when visiting your venture capitalists in Silicon Valley.
Setting Background Color
Drawings have an overall white background color by default. Background color for all components is set by default in the Tools - Options dialog. Each individual component can have its background color set by opening the component in a window and choosing View - Properties.
View - Properties - Zooms