ZoomRaster
Name
ZoomRaster --  A zoomable Raster.
Description
 ZoomRaster is a subclass of Raster that implements a zoomable image. It handles translation between logical coordinates and screen coordinates.
Methods
Phase: Using
- - (void) handleConfigureWidth:-  (unsigned) newWidth Height:-  (unsigned) newHeight-  Reconfigures the ZoomRaster when the window is resized. 
- -  setZoomFactor:-  (unsigned) z-  Set the zoom factor. 
- - (void) fillCenteredRectangleX0:-  (int) x0 Y0:-  (int) y0 X1:-  (int) x1 Y1:-  (int) y1 Color:-  (Color) color-  Special method for ZoomRasters. Like fillRectangleX0:Y0:X1:Y1:Color: in Raster, it will fill a rectangle of given geometry and color. This method makes sure that zooming the window does not change the logical position of the rectangle in relation to the logical coordinates.  In other words, if a rectangle includes point (10,10) at one zoom factors, then that same point is included for all zoom factors. 
- - (unsigned) getZoomFactor-  Get the current zoom factor. 
- - (void) decreaseZoom-  Make the raster smaller. 
- - (void) increaseZoom-  Make the raster bigger.