class GvViewArea - Gtk geographic view area.

Declared in module gview

Inheritance hierarchy:

gview.GvViewArea
gtk.GtkDrawingArea

Synopsis

class GvViewArea(GtkDrawingArea):
    def gview.GvViewArea.__init__(self, _obj=None)
    def gview.GvViewArea.active_layer(self) # Fetch the active layer for this view
    def gview.GvViewArea.add_layer(self, layer) # Add a new layer to the view window. 
    def gview.GvViewArea.copy_state(self, src_view) # Copy the view state of another view.
    def gview.GvViewArea.create_thumbnail(self, layer, w, h) # Return area thumbnail as a GdkWindow.
    def gview.GvViewArea.fit_all_layers(self) # Fit view window to extents of all layers
    def gview.GvViewArea.fit_extents(self, llx, lly, width, height) # Fit view window to region.
    def gview.GvViewArea.get_extents(self) # Fetch extents of view window.
    def gview.GvViewArea.get_height(self) # Return height of area in pixels.
    def gview.GvViewArea.get_pointer(self) # Fetch current pointer position.
    def gview.GvViewArea.get_projection(self) # Return view coordinate system.
    def gview.GvViewArea.get_translation(self) # Get view center translation.
    def gview.GvViewArea.get_width(self) # Return width of area in pixels.
    def gview.GvViewArea.height_scale(self, scale=1.0) # Set height scaling factor.
    def gview.GvViewArea.inverse_map_pointer(self, xy) # Translate position from georef coords.
    def gview.GvViewArea.list_layers(self) # Fetch list of layers attached to this view.
    def gview.GvViewArea.map_pointer(self, xy) # Translate position to georef coords.
    def gview.GvViewArea.print_postscript_to_file(self, width, height, is_rgb, filename) # Print view (at indicated resolution) to PostScript file.
    def gview.GvViewArea.print_to_file(self, width, height, filename, format='GTiff') # Print view (at indicated resolution) to raster file.
    def gview.GvViewArea.remove_layer(self, layer) # Remove a layer from view window.
    def gview.GvViewArea.rotate(self, angle) # Rotate view about center.
    def gview.GvViewArea.set_active_layer(self, layer) # Set the active layer for this view.
    def gview.GvViewArea.set_mode(self, flag_3D=0) # Set 2D/3D view mode.
    def gview.GvViewArea.set_projection(self, proj) # Set the coordinate system of the view.
    def gview.GvViewArea.set_translation(self, x, y) # Set view center translation.
    def gview.GvViewArea.swap_layers(self, layer_a, layer_b) # Swap two layers in the display order stack.
    def gview.GvViewArea.zoom(self, zoom) # Zoom in or out.

    # Inherited from gtk.GtkWidget
    def gtk.GtkWidget.__init__(self, _obj=None)
    def gtk.GtkWidget.accelerators_locked(self)
    def gtk.GtkWidget.activate(self, obj=None)
    def gtk.GtkWidget.add_accelerator(self, signal, group, key, mods, flags)
    def gtk.GtkWidget.add_events(self, events)
    def gtk.GtkWidget.destroy(self, obj=None)
    def gtk.GtkWidget.drag_begin(self, targets, actions, button, event)
    def gtk.GtkWidget.drag_dest_set(self, flags, targets, actions)
    def gtk.GtkWidget.drag_dest_set_proxy(self, proxy_window, protocol, use_coordinates)
    def gtk.GtkWidget.drag_dest_unset(self)
    def gtk.GtkWidget.drag_finish(self, context, success, delete, time)
    def gtk.GtkWidget.drag_get_data(self, context, target, time)
    def gtk.GtkWidget.drag_get_source_widget(self, context)
    def gtk.GtkWidget.drag_highlight(self)
    def gtk.GtkWidget.drag_set_default_icon(self, colormap, pixmap, mask, hot_x, hot_y)
    def gtk.GtkWidget.drag_set_icon_default(self, context)
    def gtk.GtkWidget.drag_set_icon_pixmap(self, context, colormap, pixmap, mask, hot_x, hot_y)
    def gtk.GtkWidget.drag_set_icon_widget(self, context, widget, hot_x, hot_y)
    def gtk.GtkWidget.drag_source_set(self, button_mask, targets, actions)
    def gtk.GtkWidget.drag_source_set_icon(self, colormap, pixmap, mask)
    def gtk.GtkWidget.drag_status(self, context, action, time)
    def gtk.GtkWidget.drag_unhighlight(self)
    def gtk.GtkWidget.draw(self, rect)
    def gtk.GtkWidget.draw_default(self, obj=None)
    def gtk.GtkWidget.draw_focus(self, obj=None)
    def gtk.GtkWidget.ensure_style(self)
    def gtk.GtkWidget.event(self, event)
    def gtk.GtkWidget.get_allocation(self)
    def gtk.GtkWidget.get_ancestor(self, type)
    def gtk.GtkWidget.get_child_requisition(self)
    def gtk.GtkWidget.get_colormap(self)
    def gtk.GtkWidget.get_composite_name(self)
    def gtk.GtkWidget.get_events(self)
    def gtk.GtkWidget.get_extension_events(self)
    def gtk.GtkWidget.get_name(self)
    def gtk.GtkWidget.get_parent_window(self)
    def gtk.GtkWidget.get_pointer(self)
    def gtk.GtkWidget.get_style(self)
    def gtk.GtkWidget.get_toplevel(self)
    def gtk.GtkWidget.get_window(self)
    def gtk.GtkWidget.grab_default(self, obj=None)
    def gtk.GtkWidget.grab_focus(self, obj=None)
    def gtk.GtkWidget.hide(self, obj=None)
    def gtk.GtkWidget.hide_all(self, obj=None)
    def gtk.GtkWidget.hide_on_delete(self, obj=None)
    def gtk.GtkWidget.intersect(self, rect)
    def gtk.GtkWidget.is_ancestor(self, a)
    def gtk.GtkWidget.lock_accelerators(self)
    def gtk.GtkWidget.map(self, obj=None)
    def gtk.GtkWidget.popup(self, x, y)
    def gtk.GtkWidget.queue_draw(self, obj=None)
    def gtk.GtkWidget.queue_resize(self, obj=None)
    def gtk.GtkWidget.realize(self, obj=None)
    def gtk.GtkWidget.remove_accelerator(self, group, key, mods)
    def gtk.GtkWidget.remove_accelerators(self, signal, visible_only)
    def gtk.GtkWidget.reparent(self, new_parent)
    def gtk.GtkWidget.reset_rc_styles(self)
    def gtk.GtkWidget.restore_default_style(self)
    def gtk.GtkWidget.selection_add_target(self, selection, target, info)
    def gtk.GtkWidget.selection_convert(self, selection, target, time)
    def gtk.GtkWidget.selection_owner_set(self, selection, time)
    def gtk.GtkWidget.selection_remove_all(self)
    def gtk.GtkWidget.set_app_paintable(self, app_paintable)
    def gtk.GtkWidget.set_composite_name(self, name)
    def gtk.GtkWidget.set_events(self, events)
    def gtk.GtkWidget.set_extension_events(self, exevents)
    def gtk.GtkWidget.set_name(self, name)
    def gtk.GtkWidget.set_parent(self, parent)
    def gtk.GtkWidget.set_parent_window(self, parent)
    def gtk.GtkWidget.set_rc_style(self)
    def gtk.GtkWidget.set_scroll_adjustments(self, hadj, vadj)
    def gtk.GtkWidget.set_sensitive(self, s)
    def gtk.GtkWidget.set_state(self, s)
    def gtk.GtkWidget.set_style(self, style)
    def gtk.GtkWidget.set_uposition(self, x, y)
    def gtk.GtkWidget.set_usize(self, w, h)
    def gtk.GtkWidget.shape_combine_mask(self, mask, ofs_x, ofs_y)
    def gtk.GtkWidget.show(self, obj=None)
    def gtk.GtkWidget.show_all(self, obj=None)
    def gtk.GtkWidget.show_now(self, obj=None)
    def gtk.GtkWidget.size_allocate(self, a)
    def gtk.GtkWidget.size_request(self)
    def gtk.GtkWidget.unlock_accelerators(self)
    def gtk.GtkWidget.unmap(self, obj=None)
    def gtk.GtkWidget.unparent(self)
    def gtk.GtkWidget.unrealize(self, obj=None)

    # Inherited from gtk.GtkObject
    def gtk.GtkObject.__cmp__(self, other)
    def gtk.GtkObject.__getattr__(self, attr)
    def gtk.GtkObject.__getitem__(self, key)
    def gtk.GtkObject.__hash__(self)
    def gtk.GtkObject.__init__(self, _obj=None)
    def gtk.GtkObject.__setitem__(self, key, v)
    def gtk.GtkObject.connect(self, name, f, *extra)
    def gtk.GtkObject.connect(self, name, f, *extra)
    def gtk.GtkObject.connect_after(self, name, f, *extra)
    def gtk.GtkObject.connect_after(self, name, f, *extra)
    def gtk.GtkObject.connect_object(self, name, f, obj, *extra)
    def gtk.GtkObject.connect_object(self, name, f, obj, *extra)
    def gtk.GtkObject.connect_object_after(self, name, f, obj, *extra)
    def gtk.GtkObject.destroy(self, _obj=None)
    def gtk.GtkObject.disconnect(self, id)
    def gtk.GtkObject.emit(self, signal, *args)
    def gtk.GtkObject.emit_stop_by_name(self, sig)
    def gtk.GtkObject.flags(self, mask=None)
    def gtk.GtkObject.get_data(self, key)
    def gtk.GtkObject.remove_data(self, key)
    def gtk.GtkObject.set(self, dict)
    def gtk.GtkObject.set_data(self, key, value)
    def gtk.GtkObject.set_flags(self, flags)
    def gtk.GtkObject.signal_handler_block(self, id)
    def gtk.GtkObject.signal_handler_unblock(self, id)
    def gtk.GtkObject.signal_handlers_destroy(self)
    def gtk.GtkObject.unset_flags(self, flags)

    # Inherited from gtk.GtkDrawingArea
    def gtk.GtkDrawingArea.__cache_win(self)
    def gtk.GtkDrawingArea.__init__(self, _obj=None)
    def gtk.GtkDrawingArea.draw_arc(self, gc, fill, x, y, width, height, angle1, angle2)
    def gtk.GtkDrawingArea.draw_gray_image(self, gc, x, y, width, height, dither, buffer, rowstride)
    def gtk.GtkDrawingArea.draw_line(self, gc, x1, y1, x2, y2)
    def gtk.GtkDrawingArea.draw_lines(self, gc, points)
    def gtk.GtkDrawingArea.draw_pixmap(self, gc, src, xsrc, ysrc, xdest, ydest, width, height)
    def gtk.GtkDrawingArea.draw_point(self, gc, x, y)
    def gtk.GtkDrawingArea.draw_points(self, gc, points)
    def gtk.GtkDrawingArea.draw_polygon(self, gc, fill, points)
    def gtk.GtkDrawingArea.draw_rectangle(self, gc, fill, x, y, width, height)
    def gtk.GtkDrawingArea.draw_rgb_32_image(self, gc, x, y, width, height, dither, buffer, rowstride)
    def gtk.GtkDrawingArea.draw_rgb_image(self, gc, x, y, width, height, dither, buffer, rowstride)
    def gtk.GtkDrawingArea.draw_segments(self, gc, segs)
    def gtk.GtkDrawingArea.draw_string(self, font, gc, x, y, string)
    def gtk.GtkDrawingArea.draw_text(self, font, gc, x, y, text)
    def gtk.GtkDrawingArea.size(self, w, h)

Description

Signals:

gldraw: This signal is emitted after all layers have drawn themselves but before the result is displayed to the user. It provides a hook whereby application code can do additional drawing.
active-changed: This signal is emitted after the active layer has been modified, or when a layer is added or removed from the view. It can be used to update tools that depend on the active layer.
view-state-changed: This signal is emitted after the view state changes. This includes flipping, zooming and roaming. It does not include mouse position changes.

Note that the GvViewArea is a GtkWidget, and application code may attach callbacks to the motion-notify-event, button-press-event, key-press-event and other similar events. The map_pointer() method should be used to translate raw GtkWidget coordinates to georeferenced positions.

gview.GvViewArea.add_layer(self, layer)

Add a new layer to the view window.

Arguments

layer: abc A GvLayer derived object to add to the view.

gview.GvViewArea.copy_state(self, src_view)

Copy the view state of another view.

This includes translation, rotation, and zoom factor.

src_view: the GvViewArea to copy the state from.

gview.GvViewArea.create_thumbnail(self, layer, w, h)

Return area thumbnail as a GdkWindow.

Arguments

layer: the GvLayer to render into the thumbnail.
w: Width in pixels of thumbnail.
h: Height in pixel of thumbnail.

gview.GvViewArea.fit_extents(self, llx, lly, width, height)

Fit view window to region.

The position and size of the window are in georeferenced coordinates. The translation, zoom and rotation are updated to fit the entire desired box. If the aspect ratio of the box is different than the window, then the window will display the region centered, with extra area viewed in one dimension. The rotation is always set to zero by this call.

llx: X (easting) position of the lower left corner.
lly: Y (northing) position of the lower left corner.
width: Width of view region.
height: Height of view region.

gview.GvViewArea.get_extents(self)

Fetch extents of view window.

The extents are returned as an (xmin,ymin,xmax,ymax) tuple in georeferenced coordinates.

gview.GvViewArea.get_pointer(self)

Fetch current pointer position.

The pointer value is returned as an (X,Y) tuple in georeferenced coordinates.

gview.GvViewArea.get_projection(self)

Return view coordinate system.

The coordinate system is returned in OGC WKT format, and will likely be an empty string if there is no coordinate system.

gview.GvViewArea.get_translation(self)

Get view center translation.

The translation values are in georeferenced coordinates, and to put the value (1000,2000) at the view center a translation of (-1000,-2000) would be returned. The value is returned as an (x,y) tuple.

gview.GvViewArea.height_scale(self, scale=1.0)

Set height scaling factor.

Has no effect unless in 3D mode. A scale value of 2.0 will exaggerate all elevations by a factor of 2 relative to horizontal (georeferenced) coordinates.

scale: scale factor (originally 1.0)

gview.GvViewArea.inverse_map_pointer(self, xy)

Translate position from georef coords.

Translates a map (georeferenced) position into pixel/line coordinates within the GvViewArea on screen.Returns an (x,y) tuple in pixel/line coordinates.

xy: (x,y) tuple in georeferenced coordinates

gview.GvViewArea.map_pointer(self, xy)

Translate position to georef coords.

Translates a pixel/line position into map (georeferenced) coordinates within the view. The pixel/line coordinates might come from a raw GdkEvent, for instance.Returns an (x,y) tuple in georeferenced coordinates.

xy: (x,y) tuple in GvViewArea pixel coordinates

gview.GvViewArea.print_postscript_to_file(self, width, height, is_rgb, filename)

Print view (at indicated resolution) to PostScript file.

width: the desired raster width at which to render the image.
height: the desired raster height at which to render the image.
is_rgb: non-zero for RGB output or zero for greyscale output.
filename: the name of the file to write to.

If the aspect ratio of width:height is not the same as the aspect ratio of the view, the extents will be extended in one direction to ensure the entire view data is visible.This method return 0 on success or non-zero on failure.

gview.GvViewArea.print_to_file(self, width, height, filename, format='GTiff')

Print view (at indicated resolution) to raster file.

width: the desired raster width at which to render the image.
height: the desired raster height at which to render the image.
filename: the name of the file to write to.
format: the GDAL format to use (defaults to 'GTiff').

gview.GvViewArea.remove_layer(self, layer)

Remove a layer from view window.

Arguments

layer: the layer to remove

gview.GvViewArea.rotate(self, angle)

Rotate view about center.

angle: the angle to rotate about the center by in degrees. Positive is causes view contents to rotate counter-clockwise.

gview.GvViewArea.set_active_layer(self, layer)

Set the active layer for this view.

It is an error to make a layer active if it has not already been added to the view.

Arguments

layer: GvLayer to make active.

gview.GvViewArea.set_mode(self, flag_3D=0)

Set 2D/3D view mode.

Set the view mode to either 2D orthonormal projection or 3D perspective projection.

flag_3D: Either gview.MODE_2D or gview.MODE_3D

gview.GvViewArea.set_projection(self, proj)

Set the coordinate system of the view.

Currently the only time the coordinate system can be modified is when there are no layers attached. When raster layers are added to the view, they will attempt to reproject themselves to match the view if possible. Vector layers do not currently do this.

proj: new coordinate system in OGC WKT.

gview.GvViewArea.set_translation(self, x, y)

Set view center translation.

The translation values are in georeferenced coordinates, and to put the value (1000,2000) at the view center a translation of (-1000,-2000) is needed.

x: the X (easting) value for view center translation.
y: the Y (northing) value for view center translation.

gview.GvViewArea.swap_layers(self, layer_a, layer_b)

Swap two layers in the display order stack.

Arguments

layer_a: First GvLayer to switch.
layer_b: Second GvLayer to switch.

gview.GvViewArea.zoom(self, zoom)

Zoom in or out.

Note that the zoom value is log base 2 of the linear zoom factor. So to zoom in by a factor of 2, you would pass 1. To zoom in by a factor of 8 you would pass 3. To zoom out by a factor of eight you would pass -8.

zoom: the value to add to the current zoom factor.