Fix rectangle logic

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@2831 42af7a65-404d-4744-a932-0658087f49c3

ChangeLog

@@ -1185,3 +1185,7 @@
 
 	* examples/nsh/nsh_telnetd.c - Fix compilation errors that happen
 	  when both DHCPC and TELNETD are enabled in the Nuttshell.
+	* graphics/nxglib/fb/nxglib_moverectangle.c - Fix a logic error
+	  that caused an uninitialized variable warning.  I still don't 
+	  have a test to prove that the changes are correct.
+

Documentation/NuttX.html

@@ -8,7 +8,7 @@
   <tr align="center" bgcolor="#e4e4e4">
     <td>
       <h1><big><font color="#3c34ec"><i>NuttX RTOS</i></font></big></h1>
-      <p>Last Updated: August 5, 2010</p>
+      <p>Last Updated: August 7, 2010</p>
     </td>
   </tr>
 </table>
@@ -1858,7 +1858,9 @@ nuttx-5.9 2010-xx-xx Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;
 
 	* examples/nsh/nsh_telnetd.c - Fix compilation errors that happen
 	  when both DHCPC and TELNETD are enabled in the Nuttshell.
-
+	* graphics/nxglib/fb/nxglib_moverectangle.c - Fix a logic error
+	  that caused an uninitialized variable warning.  I still don't 
+	  have a test to prove that the changes are correct.
 
 pascal-2.1 2010-xx-xx Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;
 

Documentation/NuttXLinks.html

@@ -25,8 +25,8 @@
       <li><a href="http://sourceforge.net/projects/nuttx/files/" target="_top">Downloads</a></li>
       <li><a href="http://sourceforge.net/projects/nuttx/files/buildroot" target="_top">Toolchains</a></li>
       <li><a href="http://nuttx.cvs.sourceforge.net/nuttx/" target="_top">Browse CVS</a></li>
-      <li><a href="freeports.html" target="header">Free Ports</a></li>
       <li><a href="http://dir.gmane.org/gmane.comp.embedded.nuttx" target="_top">gmane</a></li>
+      <li><a href="freeports.html" target="header">Free Ports</a></li>
     </td>
   </tr>
   <tr>
@@ -58,7 +58,7 @@
   </tr>
     <td>&nbsp</td>
     <td align="left" valign="top">
-      <a href="http://rss.groups.yahoo.com/group/nuttx/rss"><img src="rss.gif" border="0"></a></td>
+      <a href="http://rss.groups.yahoo.com/group/nuttx/rss" target="_top"><img src="rss.gif" border="0"></a></td>
   <tr>
   </tr>
 </table>

TODO

@@ -12,7 +12,7 @@ NuttX TODO List (Last updated August 7, 2010)
   (1)  USB (drivers/usbdev)
   (5)  Libraries (lib/)
  (12)  File system/Generic drivers (fs/, drivers/)
-  (3)  Graphics subystem (graphics/)
+  (2)  Graphics subystem (graphics/)
   (1)  Pascal add-on (pcode/)
   (1)  Documentation (Documentation/)
   (6)  Build system / Toolchains
@@ -465,15 +465,6 @@ o Graphics subystem (graphics/)
   Status:      Open
   Priority:    Low (unless you need the p13201 then it is certainly higher).
 
-  Description: When building for a framebuffer driver, there are warnings that a
-               symbol is used before being initialized in graphics/nxglib/ in all
-               of the auto-generated files named nxglib_moverectangle_*bpp.c.  This
-               looks like a real error and must be fixed.  I don't think that the
-               moverectangle logic is currently being used in any of the examples,
-               so this should not be a big problem.
-  Status:      Open
-  Priority:    Medium-to-High
-
 o Pascal Add-On (pcode/)
   ^^^^^^^^^^^^^^^^^^^^^^
 

graphics/nxglib/fb/nxglib_moverectangle.c

@@ -174,44 +174,71 @@ void NXGL_FUNCNAME(nxgl_moverectangle,NXGLIB_SUFFIX)
 # endif
 #endif
 
-  /* Case 1:  The destination position (offset) is above the displayed
+  /* sline = address of the first pixel in the top row of the source in
-   * position (rect)
+   * framebuffer memory
    */
 
-  if (offset->y < rect->pt1.y)
-    {
-      /* Copy the rectangle from top down. */
-
   sline = pinfo->fbmem + rect->pt1.y * stride + NXGL_SCALEX(rect->pt1.x);
+
+  /* dline = address of the first pixel in the top row of the destination
+   * in framebuffer memory.  We get dline by subtract the offset from the
+   * source position.
+   */
+
   dline = (FAR uint8_t*)sline - offset->y * stride - NXGL_SCALEX(offset->x);
 
+  /* Case 1:  Is the destination position above the displayed position?
+   * If the Y offset is negative, then the destination is offset to a
+   * postion below (or to the right) in the source in framebuffer memory.
+   */
+
+  if (offset->y < 0)
+    {
+      /* Yes.. Copy the rectangle from top down (i.e., adding the stride
+       * to move to the next, lower row) */
+
       while (rows--)
         {
+          /* Copy the row */
+
 #if NXGLIB_BITSPERPIXEL < 8
           nxgl_lowresmemcpy(dline, sline, width, leadmask, tailmask);
 #else
           NXGL_MEMCPY(dline, sline, width);
 #endif
+          /* Point to the next source/dest row below the current one */
+
           dline += stride;
           sline += stride;
         }
     }
 
-  /* Case 2: The destination position (offset) is below the displayed
+  /* Case 2: No.. the destination position is above (or to the left of)
-   * position (rect)
+   * the displayed source position
    */
 
   else
     {
-      /* Copy the rectangle from the bottom up */
+      /* Adjust sline and dline to point to the bottom row (+1) of the
+       * source and destination rectangles in framebuffer memory.
+       */
 
-      sline = pinfo->fbmem + rect->pt2.y * stride + NXGL_SCALEX(rect->pt1.x);
+      unsigned int hoffset = rows * stride;
-      dline = (FAR uint8_t*)sline - offset->y * stride - NXGL_SCALEX(offset->x);
+      sline += hoffset;
+      dline += hoffset;
+
+      /* Copy the rectangle from the bottom up (i.e., subtracting stride
+       * to re-position to the previous, higher row) */
 
       while (rows--)
         {
+          /* Point to the next source/dest row above the current one */
+
           dline -= stride;
           sline -= stride;
+
+          /* Copy the row */
+
 #if NXGLIB_BITSPERPIXEL < 8
           nxgl_lowresmemcpy(dline, sline, width, leadmask, tailmask);
 #else