- Moved the dw2 tree into dillo2's tree.

1 files changed, 204 insertions, 0 deletions

diff --git a/dw/view.hh b/dw/view.hh
new file mode 100644
index 00000000..ef604549
--- /dev/null
+++ b/dw/view.hh
@@ -0,0 +1,204 @@
+#ifndef __DW_VIEW_HH__
+#define __DW_VIEW_HH__
+
+#ifndef __INCLUDED_FROM_DW_CORE_HH__
+#   error Do not include this file directly, use "core.hh" instead.
+#endif
+
+namespace dw {
+namespace core {
+
+/**
+ * \brief An interface to encapsulate platform dependent drawing.
+ *
+ * \sa\ref dw-overview, \ref dw-layout-views
+ */
+class View: public object::Object
+{
+public:
+   /*
+    * ----------------------------
+    *    Operations on the view
+    * ----------------------------
+    */
+
+   /**
+    * \brief This methods notifies the view, that it has been attached to a
+    *    layout.
+    */
+   virtual void setLayout (Layout *layout) = 0;
+
+   /**
+    * \brief Set the canvas size.
+    */
+   virtual void setCanvasSize (int width, int ascent, int descent) = 0;
+
+   /**
+    * \brief Set the cursor appearance. 
+    */
+   virtual void setCursor (style::Cursor cursor) = 0;
+
+   /**
+    * \brief Set the background of the view.
+    */
+   virtual void setBgColor (style::Color *color) = 0;
+   
+   /*
+    * ---------------------------------------------------------
+    *    Scrolling and Related. Only usesViewport must be
+    *    implemented, if it returns false, the other methods
+    *    are never called.
+    * ---------------­-----------­-----------------------------
+    */
+
+   /**
+    * \brief Return, whether this view uses a viewport.
+    */
+   virtual bool usesViewport () = 0;
+
+   /**
+    * \brief Get the thickness of the horizontal scrollbar, when it is
+    *    visible.
+    *
+    * Does not have to be implemented, when usesViewport returns false.
+    */
+   virtual int getHScrollbarThickness () = 0;
+
+   /**
+    * \brief Get the thickness of the vertical scrollbar, when it is
+    *    visible.
+    *
+    * Does not have to be implemented, when usesViewport returns false.
+    */
+   virtual int getVScrollbarThickness () = 0;
+
+   /**
+    * \brief Scroll the vieport to the given position.
+    *
+    * Does not have to be implemented, when usesViewport returns false.
+    */
+   virtual void scrollTo (int x, int y) = 0;
+
+   /**
+    * \brief Set the viewport size.
+    *
+    * Does not have to be implemented, when usesViewport returns false.
+    *
+    * This will normally imply a resize of the UI widget. Width and height are
+    * the dimensions of the new size, \em including the scrollbar thicknesses.
+    *
+    * \bug The rest of this comment needs to be updated.
+    *
+    * markerWidthDiff and markerHeightDiff are the respective dimensions of
+    * the viewport markers (see dw::core::getMarkerWidthDiff and
+    * dw::core::getMarkerHeightDiff), if they are 0, the respective
+    * marker should not be shown at all.
+    */
+   virtual void setViewportSize (int width, int height,
+                                 int hScrollbarThickness,
+                                 int vScrollbarThickness) = 0;
+
+   /*
+    * -----------------------
+    *    Drawing functions
+    * -----------------------
+    */
+
+   /**
+    * \brief Called before drawing.
+    *
+    * All actual drawing operations will be enclosed into calls of 
+    * dw::core:View::startDrawing and dw::core:View::finishDrawing. They
+    * may be implemented, e.g. when a backing
+    * pixmap is used, to prevent flickering. StartDrawing() will then
+    * initialize the backing pixmap, all other drawing operations will draw
+    * into it, and finishDrawing() will merge it into the window.
+    */
+   virtual void startDrawing (Rectangle *area) = 0;
+
+   /**
+    * \brief Called after drawing.
+    *
+    * \sa dw::core:View::startDrawing
+    */
+   virtual void finishDrawing (Rectangle *area) = 0;
+
+   /**
+    * \brief Queue a region, which is given in \em canvas coordinates, for
+    *    drawing.
+    *
+    * The view implementation is responsible, that this region is drawn, either
+    * immediately, or (which is more typical, since more efficient) the areas
+    * are collected, combined (as far as possible), and the drawing is later
+    * done in an idle function.
+    */
+   virtual void queueDraw (Rectangle *area) = 0;
+
+   /**
+    * \brief Queue the total viewport for drawing.
+    *
+    * \sa dw::core::View::queueDraw
+    */
+   virtual void queueDrawTotal () = 0;
+
+   /**
+    * \brief Cancel a draw queue request.
+    *
+    * If dw::core::View::queueDraw or dw::core::View::queueDrawTotal have been
+    * called before, and the actual drawing was not processed yet, the actual
+    * drawing should be cancelled. Otherwise, the cancellation should be
+    * ignored.
+    */
+   virtual void cancelQueueDraw () = 0;
+
+   /*
+    * The following methods should be self-explaining.
+    */
+
+   virtual void drawPoint     (style::Color *color,
+                               style::Color::Shading shading,
+                               int x, int y) = 0;
+   virtual void drawLine      (style::Color *color,
+                               style::Color::Shading shading,
+                               int x1, int y1, int x2, int y2) = 0;
+   virtual void drawRectangle (style::Color *color,
+                               style::Color::Shading shading, bool filled,
+                               int x, int y, int width, int height) = 0;
+   virtual void drawArc       (style::Color *color,
+                               style::Color::Shading shading, bool filled,
+                               int x, int y, int width, int height,
+                               int angle1, int angle2) = 0;
+   virtual void drawPolygon    (style::Color *color,
+                                style::Color::Shading shading,
+                                bool filled, int points[][2], int npoints) = 0;
+   virtual void drawText       (style::Font *font,
+                                style::Color *color,
+                                style::Color::Shading shading,
+                                int x, int y, const char *text, int len) = 0;
+
+   virtual void drawImage (Imgbuf *imgbuf, int xRoot, int yRoot,
+                           int x, int y, int width, int height) = 0;
+
+   /*
+    * --------------
+    *    Clipping
+    * --------------
+    */
+
+   /*
+    * To prevent drawing outside of a given area, a clipping view may be
+    * requested, which also implements this interface. The clipping view is
+    * related to the parent view (clipping views may be nested!), anything
+    * which is drawn into this clipping view, is later merged again into the
+    * parent view. An implementation will typically use additional pixmaps,
+    * which are later merged into the parent view pixmap/window.
+    */
+
+   virtual View *getClippingView (int x, int y, int width, int height) = 0;
+   virtual void mergeClippingView (View *clippingView) = 0;
+};
+
+} // namespace dw
+} // namespace core
+
+#endif // __DW_VIEW_HH__