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Enhancements
38
The opaque pattern fills a tile with a single color. Color-interpolating visualization and
all variants of enumeration visualization use this “pattern”.
The vertical bar pattern draws a vertical bar with a specific relative height inside the
tile. GCspy uses this mode exclusively for the vertical bar visualization mode.
The invalid pattern draws a question mark on a red background inside the tile. This
pattern is used to indicate tiles with invalid values, for example because the values
is outside the stream’s boundaries.
Figure 5.6 depicts the classes responsible for rendering tiles, including the FillPattern
interface and three of its implementations. The interaction between these classes is
characterized in the following.
gcspy::vis
TileComponent
style
tileFlags
selected
marked
setTile(tile : Tile)
paintComponent(g : Graphics)
«interface»
FillPattern
«use»
fill(g : Graphics,area : Rectangle)
java::awt
«realize»
«realize»
OpaquePattern
HorizontalLinesPattern
spacing
thickness
«use»
«realize»
DotsPattern
Graphics
spacing
diameter
«use»
«use»
setColor(c)
fillRect(x,y,w,h)
fillPolygon(points)
fillOval(x,y,w,h)
Figure 5.6: Diagram of classes responsible for rendering tiles
As described earlier in Section 5.3, JList asks TileRenderer to provide a component for
drawing a specific tile on the screen. TileRenderer returns a TileComponent instance
that is configured to draw the tile in question. JList calls the paintComponent()
method of TileComponent and passes a Graphics object that provides methods to
perform the actual drawing. TileComponent in turn calls the fill() method of the
appropriate FillPattern implementation and passes the Graphics object as well as
the rectangular area that should be painted. TileComponent itself also draws additional