diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/ld-canvas.c | 48 | ||||
| -rw-r--r-- | src/ld-canvas.h | 4 |
2 files changed, 27 insertions, 25 deletions
diff --git a/src/ld-canvas.c b/src/ld-canvas.c index bc93902..0667adb 100644 --- a/src/ld-canvas.c +++ b/src/ld-canvas.c @@ -27,7 +27,7 @@ * @short_description: A canvas. * @see_also: #LdDiagram * - * #LdCanvas is used for displaying #LdDiagram objects. + * #LdCanvas displays and enables the user to manipulate with an #LdDiagram. */ /* Milimetres per inch. */ @@ -478,7 +478,7 @@ ld_canvas_get_scale_in_px (LdCanvas *self) } /** - * ld_canvas_translate_canvas_coordinates: + * ld_canvas_widget_to_diagram_coords: * @self: An #LdCanvas object. * @x: The X coordinate to be translated. * @y: The Y coordinate to be translated. @@ -487,27 +487,28 @@ ld_canvas_get_scale_in_px (LdCanvas *self) * into diagram coordinates. */ void -ld_canvas_translate_canvas_coordinates (LdCanvas *self, gdouble *x, gdouble *y) +ld_canvas_widget_to_diagram_coords (LdCanvas *self, gdouble *x, gdouble *y) { GtkWidget *widget; gdouble scale; g_return_if_fail (LD_IS_CANVAS (self)); + g_return_if_fail (x != NULL); + g_return_if_fail (y != NULL); widget = GTK_WIDGET (self); scale = ld_canvas_get_scale_in_px (self); /* We know diagram coordinates of the center of the canvas, so we may * translate the given X and Y coordinates to this center and then scale - * them by dividing them by the length of the base unit in pixels - * times zoom of the canvas. + * them by dividing them by the current scale. */ *x = self->priv->x + (*x - (widget->allocation.width * 0.5)) / scale; *y = self->priv->y + (*y - (widget->allocation.height * 0.5)) / scale; } /** - * ld_canvas_translate_diagram_coordinates: + * ld_canvas_diagram_to_widget_coords: * @self: An #LdCanvas object. * @x: The X coordinate to be translated. * @y: The Y coordinate to be translated. @@ -515,18 +516,20 @@ ld_canvas_translate_canvas_coordinates (LdCanvas *self, gdouble *x, gdouble *y) * Translate diagram coordinates into canvas coordinates. */ void -ld_canvas_translate_diagram_coordinates (LdCanvas *self, +ld_canvas_diagram_to_widget_coords (LdCanvas *self, gdouble *x, gdouble *y) { GtkWidget *widget; gdouble scale; g_return_if_fail (LD_IS_CANVAS (self)); + g_return_if_fail (x != NULL); + g_return_if_fail (y != NULL); widget = GTK_WIDGET (self); scale = ld_canvas_get_scale_in_px (self); - /* Just the reversal of ld_canvas_translate_canvas_coordinates(). */ + /* Just the reversal of ld_canvas_widget_to_diagram_coords(). */ *x = scale * (*x - self->priv->x) + 0.5 * widget->allocation.width; *y = scale * (*y - self->priv->y) + 0.5 * widget->allocation.height; } @@ -544,8 +547,7 @@ on_expose_event (GtkWidget *widget, GdkEventExpose *event, gpointer user_data) data.exposed_rect.width = event->area.width; data.exposed_rect.height = event->area.height; - cairo_rectangle (data.cr, data.exposed_rect.x, data.exposed_rect.y, - data.exposed_rect.width, data.exposed_rect.height); + gdk_cairo_rectangle (data.cr, &event->area); cairo_clip (data.cr); /* Paint the background white. */ @@ -562,27 +564,27 @@ on_expose_event (GtkWidget *widget, GdkEventExpose *event, gpointer user_data) static void draw_grid (GtkWidget *widget, DrawData *data) { - gdouble x_top, y_top; + gdouble x_init, y_init; gdouble x, y; cairo_set_source_rgb (data->cr, 0.5, 0.5, 0.5); cairo_set_line_width (data->cr, 1); cairo_set_line_cap (data->cr, CAIRO_LINE_CAP_ROUND); - /* Get coordinates of the most top-left grid point. */ - x_top = data->exposed_rect.x; - y_top = data->exposed_rect.y; - ld_canvas_translate_canvas_coordinates (data->self, &x_top, &y_top); - x_top = ceil (x_top); - y_top = ceil (y_top); - ld_canvas_translate_diagram_coordinates (data->self, &x_top, &y_top); + /* Get coordinates of the top-left point. */ + x_init = data->exposed_rect.x; + y_init = data->exposed_rect.y; + ld_canvas_widget_to_diagram_coords (data->self, &x_init, &y_init); + x_init = ceil (x_init); + y_init = ceil (y_init); + ld_canvas_diagram_to_widget_coords (data->self, &x_init, &y_init); /* Iterate over all the points. */ - for (x = x_top; x <= data->exposed_rect.x + data->exposed_rect.width; - x += data->scale) + for (x = x_init; x <= data->exposed_rect.x + data->exposed_rect.width; + x += data->scale) { - for (y = y_top; y <= data->exposed_rect.y + data->exposed_rect.height; - y += data->scale) + for (y = y_init; y <= data->exposed_rect.y + data->exposed_rect.height; + y += data->scale) { cairo_move_to (data->cr, x, y); cairo_line_to (data->cr, x, y); @@ -643,7 +645,7 @@ draw_symbol (LdDiagramSymbol *diagram_symbol, DrawData *data) x = ld_diagram_object_get_x (LD_DIAGRAM_OBJECT (diagram_symbol)); y = ld_diagram_object_get_y (LD_DIAGRAM_OBJECT (diagram_symbol)); - ld_canvas_translate_diagram_coordinates (data->self, &x, &y); + ld_canvas_diagram_to_widget_coords (data->self, &x, &y); /* TODO: Rotate the space for other orientations. */ cairo_save (data->cr); diff --git a/src/ld-canvas.h b/src/ld-canvas.h index 6f2c1db..435163a 100644 --- a/src/ld-canvas.h +++ b/src/ld-canvas.h @@ -70,9 +70,9 @@ LdDiagram *ld_canvas_get_diagram (LdCanvas *self); void ld_canvas_set_library (LdCanvas *self, LdLibrary *library); LdLibrary *ld_canvas_get_library (LdCanvas *self); -void ld_canvas_translate_canvas_coordinates (LdCanvas *self, +void ld_canvas_widget_to_diagram_coords (LdCanvas *self, gdouble *x, gdouble *y); -void ld_canvas_translate_diagram_coordinates (LdCanvas *self, +void ld_canvas_diagram_to_widget_coords (LdCanvas *self, gdouble *x, gdouble *y); /* TODO: The rest of the interface. */ |