Initial import of Dillo

devdoc/dw-overview.doc

@@ -0,0 +1,158 @@
+/** \page dw-overview Dillo Widget Overview
+
+Note: If you are already familiar with the Gtk+-based version of Dw,
+read \ref dw-changes.
+
+
+The module Dw (Dillo Widget) is responsible for the low-level rendering of
+all resources, e.g. images, plain text, and HTML pages (this is the
+most complex type). Dw is \em not responsible for parsing HTML, or
+decoding image data. Furthermore, the document tree, which is planned
+for CSS, is neither a part of Dw, instead, it is a new module on top
+of Dw.
+
+The rendering, as done by Dw, is split into two phases:
+
+<ul>
+<li> the \em layouting, this means calculating the exact positions of
+     words, lines, etc. (in pixel position), and
+<li> the \em drawing, i.e. making the result of the layouting visible
+     on the screen.
+</ul>
+
+The result of the layouting allocates an area, which is called
+\em canvas.
+
+<h2>Structure</h2>
+
+The whole Dw module can be split into the following parts:
+
+\dot
+digraph G {
+   node [shape=record, fontname=Helvetica, fontsize=10];
+   edge [arrowhead="open", fontname=Helvetica, fontsize=10,
+         labelfontname=Helvetica, labelfontsize=10,
+         color="#404040", labelfontcolor="#000080"];
+
+   subgraph cluster_core {
+      style="dashed"; color="#000080"; fontname=Helvetica; fontsize=10;
+      label="Platform independent core";
+
+      Layout [URL="\ref dw::core::Layout"];
+      Platform [URL="\ref dw::core::Platform", color="#ff8080"];
+      View [URL="\ref dw::core::View", color="#ff8080"];
+      Widget [URL="\ref dw::core::Widget", color="#a0a0a0"];
+   }
+
+   subgraph cluster_fltk {
+      style="dashed"; color="#000080"; fontname=Helvetica; fontsize=10;
+      label="FLTK specific part (as an\nexample for the platform specific\n\
+implementations)";
+
+      subgraph cluster_fltkcore {
+         style="dashed"; color="#000080"; fontname=Helvetica; fontsize=10;
+         label="FLTK core";
+
+         FltkPlatform [URL="\ref dw::fltk::FltkPlatform"];
+         FltkView [URL="\ref dw::fltk::FltkView", color="#ff8080"];
+      }
+
+      FltkViewport [URL="\ref dw::fltk::FltkViewport"];
+      FltkPreview [URL="\ref dw::fltk::FltkPreview"];
+   }
+
+   subgraph cluster_widgets {
+      style="dashed"; color="#000080"; fontname=Helvetica; fontsize=10;
+      label="Platform independent widgets";
+
+      Textblock [URL="\ref dw::Textblock"];
+      AlignedTextblock [URL="\ref dw::AlignedTextblock", color="#a0a0a0"];
+      Table [URL="\ref dw::Table"];
+      Image [URL="\ref dw::Image"];
+      etc1 [label="..."];
+      etc2 [label="..."];
+   }
+
+   Layout -> Platform [headlabel="1", taillabel="1"];
+   Layout -> View [headlabel="*", taillabel="1"];
+
+   Layout -> Widget [headlabel="1", taillabel="1", label="topLevel"];
+   Widget -> Widget [headlabel="*", taillabel="1", label="children"];
+
+   Widget -> Textblock [arrowhead="none", arrowtail="empty", dir="both"];
+   Widget -> Table [arrowhead="none", arrowtail="empty", dir="both"];
+   Widget -> Image [arrowhead="none", arrowtail="empty", dir="both"];
+   Widget -> etc1 [arrowhead="none", arrowtail="empty", dir="both"];
+   Textblock -> AlignedTextblock [arrowhead="none", arrowtail="empty",
+                                  dir="both"];
+   AlignedTextblock -> etc2 [arrowhead="none", arrowtail="empty", dir="both"];
+
+   Platform -> FltkPlatform [arrowhead="none", arrowtail="empty", dir="both",
+                             style="dashed"];
+   FltkPlatform -> FltkView [headlabel="*", taillabel="1"];
+
+   View -> FltkView [arrowhead="none", arrowtail="empty", dir="both"];
+   FltkView -> FltkViewport [arrowhead="none", arrowtail="empty", dir="both",
+                             style="dashed"];
+   FltkView -> FltkPreview [arrowhead="none", arrowtail="empty", dir="both",
+                            style="dashed"];
+}
+\enddot
+
+<center>[\ref uml-legend "legend"]</center>
+
+\em Platform means in most cases the underlying UI toolkit
+(e.g. FLTK). A layout is bound to a specific platform, but multiple
+platforms may be handled in one program.
+
+A short overview:
+
+<ul>
+<li> dw::core::Layout is the central class, it manages the widgets and the
+     view, and provides delegation methods for the platform.
+
+<li> The layouting is done by a tree of widgets (details are described in
+     \ref dw-layout-widgets), also the drawing, which is finally delegated
+     to the view.
+
+<li> The view (implementation of dw::core::View) provides primitive methods
+     for drawing, but also have an influence on
+     the canvas size (via size hints). See \ref dw-layout-views for details.
+
+<li> Some platform dependencies are handled by implementations
+     of dw::core::Platform.
+</ul>
+
+
+<h3>Header Files</h3>
+
+The structures mentioned above can be found in the following header
+files:
+
+<ul>
+<li> Anything from the Dw core in core.hh. Do not include the single files.
+
+<li> The single widgets can be found in the respective header files, e.g.
+     image.hh for dw::Image.
+
+<li> The core of the FLTK implementation is defined in fltkcore.hh. This
+     includes dw::fltk::FltkPlatform, dw::fltk::FltkView, but not the concrete
+     view implementations.
+
+<li> The views can be found in single header files, e.g fltkviewport.hh for
+     dw::fltk::FltkViewport.
+</ul>
+
+
+<h2>Further Documentations</h2>
+
+A complete map can be found at \ref dw-map.
+
+<ul>
+<li> For learning, how to use Dw, read \ref dw-usage and related documents,
+     dw::core::style, dw::core::ui and \ref dw-images-and-backgrounds.
+<li> Advanced topics are described in \ref dw-layout-widgets,
+     \ref dw-widget-sizes and \ref dw-layout-views.
+</ul>
+
+*/