* GeoGraphics are passed to Layers by theme to the paintScaled(GeoGraphics gg) * methiod.
* Origionaly, layers used a paintScaled(Graphics g, Scaler s, Style st...) method
* however, each additional item required a re-write of the Layer interface.
* By passing a GeoGraphics object, additonal features can be added more easely.
* @author James Macgill
* @since 0.6
* @version 0.7.1 12/Jan/00
*/
public class GeoGraphics
{
/**
* Layers can be passed a reason code to tell them why they have to repaint
* at the moment there is only one reason, 0, but this may be used for
* further expantion
*/
protected int reason = (int)0;
/**
* Contains info on filling, outlining and the like
*/
protected ShadeStyle style = (uk.ac.leeds.ccg.geotools.ShadeStyle)null;
/**
* contains id/value information that can be used for passing to the shader
*/
protected GeoData data = (GeoData)null;
/**
* contains id/text information that can be used for display as a label
*/
protected GeoData labelData = (GeoData)null;
/**
* will process value/colour lookups for the layer.
*/
protected Shader shade = (uk.ac.leeds.ccg.geotools.Shader)null;
/**
* Provides scaling services to match the view that this layer will be
* drawn in.
*/
protected Scaler scale = (uk.ac.leeds.ccg.geotools.Scaler)null;
/**
* A standard awt.Graphics object.
*/
protected java.awt.Graphics graphics = null;
/**
* When not null, layers should check against the filter to see if
* each feature should actualy be drawn by passing the filter its id.
*/
protected Filter filter = null;
/**
* Used to store the stroke width for lines.
*/
protected int width = 1;
/**
* Default constructor, not acutaly of much use to anyone.
*/
public GeoGraphics(){
}
/**
* A full constructor for a GeoGraphics object.
* @version 0.7.1
*
* @param g A standard awt.Graphics object, where the painting should take palce
* @param scale Used to convert GeoPoints into screen coordinates for the viewer
* @param shade Provides value/colour lookup for layers
* @param data Provides id/value lookup for representing data.
* @param style Contains information on filling and outlineing.
* @param filter Provides id/visible lookup for filtering out features
* @param reason A reason code for why a redraw is needed, not used at present.
*/
public GeoGraphics(Graphics g,Scaler scale,Shader shade,GeoData data,GeoData labelData,ShadeStyle style,Filter filter,int reason){
graphics = g;
this.scale = scale;
this.shade = shade;
this.data = data;
this.style = style;
this.reason = reason;
this.filter = filter;
this.labelData = labelData;
}
/**
* Find out why this GeoGraphics was created
* not used at present, but may be used for future expantion
* @return reason an int value that marks the code for the reason, not used yet.
*/
public int getReason()
{
return reason;
}
/**
* Get the awt.Graphics object so that some painting can actualy be done.
* This will tipicaly give you inderict access to the Viewers display.
* The graphics object will actualy be to some form of offscreen buffer, because of this
* there is no need for users to implement any form of buffering themselves.
*
* @return Graphics An awt Graphics object that can be drawn to as normal.
*/
public Graphics getGraphics(){
return graphics;
}
/**
* Change the graphics object contained by this object.
* Probaly not needed, as it would be better to create a new GeoGraphics object instead.
*/
public void setGraphics(Graphics g){
graphics = g;
}
public void setReason(int propValue)
{
int temp = reason;
reason = propValue;
}
/**
* Get the style object so that info on filling, outlining can be obtained.
* @return ShadeStyle the Style object.
*/
public ShadeStyle getStyle()
{
return style;
}
public void setStyle(uk.ac.leeds.ccg.geotools.ShadeStyle propValue)
{
uk.ac.leeds.ccg.geotools.ShadeStyle temp = style;
style = propValue;
}
/**
* Get the data which should be used in this display
* @return GeoData A GeoData object against which id/value lookups should be performed.
*/
public GeoData getData()
{
return data;
}
/**
* Get the label data which should be used in this display
* @return GeoData A GeoData object against which id/text lookups should be performed.
*/
public GeoData getLabelData()
{
return labelData;
}
public void setData(GeoData propValue)
{
GeoData temp = data;
data = propValue;
}
/**
* Any value/colour lookups should be performed by passing them through the
* Shader object provided by this method.
* @return Shader the Shader object to perform value/colour lookups against.
*/
public Shader getShade()
{
return shade;
}
public void setShade(uk.ac.leeds.ccg.geotools.Shader propValue)
{
uk.ac.leeds.ccg.geotools.Shader temp = shade;
shade = propValue;
}
/**
* Any geographic coordinates can be converted into screen coordiates
* apropreate for the Graphics object by using the functions provied by the
* scaler that is returned by this mehtod.
* @return Scaler for performing scaleing operations.
*/
public Scaler getScale()
{
return scale;
}
public void setScale(uk.ac.leeds.ccg.geotools.Scaler propValue)
{
uk.ac.leeds.ccg.geotools.Scaler temp = scale;
scale = propValue;
}
public void setFilter(Filter f){
filter = f;
}
/**
* Filters allow featutres to be 'switched off' by id.
* By passing the id of any feature to the filter provided by this
* method, layers can check what features should be filtered out.
* @return Filter N.B. can be null, in which case no filtering should be performed.
*/
public Filter getFilter(){
return filter;
}
}