Changes between Version 7 and Version 8 of TEXT_LAYOUT_LAZY

Timestamp:

02/14/10 12:26:50 (15 years ago)

Author:

kyli

Comment:

--

TEXT_LAYOUT_LAZY

@@ -30 +30 @@
 
 = Design =
-First of all, create class VisibleArea - composition of ImmArea and visibility flag. It will be immutable, with only one constructor and getters for the area and the visibility value. It will be used for the layout purposes, to it should be in that package.
+First of all, create class '''VisibleArea''' - composition of ImmArea and visibility flag. It will be immutable, with only one constructor and getters for the area and the visibility value. It will be used for the layout purposes, to it should be in that package.
 
 Split the anonymous SceneTextView from the HeadTextFrameView, since the class has become too large. 
 
-In the SceneTextView's TextViewFlow, except the method getAreas(), add getVisibleAreas(). It will get the areas from the chain and the visible() value of the corresponding frame, and construct a VisibleArea from both. Then the getAreas() method will use getVisibleAreas() to create a list of ImmArea-s.
+In the SceneTextView's TextViewFlow, except the method getAreas(), add '''getVisibleAreas()'''. It will get the areas from the chain and the visible() value of the corresponding frame, and construct a VisibleArea from both. Then the getAreas() method will use getVisibleAreas() to create a list of ImmArea-s.
 
-In RootPageView, override the computeVisible() method so that it returns true when the view is current in its parent book view. According to the default implementation of BaseVisualElement.visible(), this will cause a frame view to be visible() only when its page is current. Note, that the BaseVisualElement's visibility is not the same as the frame model's visibility channel. 
+In RootPageView, override the '''computeVisible()''' method so that it returns true when the view is current in its parent book view. According to the default implementation of BaseVisualElement.visible(), this will cause a frame view to be visible() only when its page is current. Note, that the BaseVisualElement's visibility is not the same as the frame model's visibility channel. 
 
  * As a result, the getVisibleAreas() will collect information about available areas for a chain as well as information about the current areas - the ones that the user works with.
 
-In HotAreaLayout, put a flag '''valid''' and create a constant HotAreaLayout.INVALID. It represents a layout with empty text and empty area.
+In HotAreaLayout, put a flag ''valid'' and create a constant HotAreaLayout.INVALID. It represents a layout with empty text and empty area.
 
-Introduce HotLayoutStatus. This way the logic will know how to handle the current layout. A HotLayoutStatus is defined for a concrete HotTextLayout and given ImmHotText and a list of VisibleArea-s as follows: 
+Introduce '''HotLayoutStatus'''. This way the logic will know how to handle the current layout. A HotLayoutStatus is defined for a concrete HotTextLayout and given ImmHotText and a list of VisibleArea-s as follows: 
 
  * INVALID, if any of these is true:
@@ -57 +57 @@
     * The status is not VALID.
 
+In HotTextLayout, create method '''update(ImmHotText, ImmList<VisibleArea>, int)'''. It returns a new HotTextLayout and its body is almost the same as the static create(..) method, except that it does not take argument ''prevLayout'' - the previous layout is the layout itself. This lets us remove some null-checks and other if-s. 
+
+The last argument in the update() is a ''lazy factor''. It indicates how lazy the algorithm should be. If you pass 0, it will be as lazy as possible. If out pass Integer.MAX_INT, it should work as the current layout. I think this factor will be useful for future testing and for dry-runs.
+
+The main difference between the 2 algorithms is, that the update method creates/reuses area layouts only to the last visible area index + the lazy factor. The rest layouts are HotAreaLayout.INVALID. As a result, this method will generate:
+
+ * PARTIALLY_VALID layout (according the the given text and areas), if (''last visible index'' + ''lazy factor'') < ''The area list's size'';
+ * VALID layout (according the the given text and areas), otherwise.
+
+After this, the create() method will look like ''HotTextLayout.EMPTY.update(..)''.
+
+Create method '''validateNextArea()''' in HotTextLayout, which returns a new HotTextLayout with just one more valid area. Everything else will be re-used, so this method is as quick as HotAreaLayout permits.
+
+
 = Implementation =
 ^(Describe and link the implementation results here (from the wiki or the repository).)^